Unusual Endolymphatic Sac Tumor: Case Report and Literature Review

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These tumors could be associated with Von Hippel-Lindau disease or isolated. These tumors mostly present with audiovestibular and neurological symptoms. The definitive diagnosis can be achieved through histopathological examination of the post-surgical excised specimen. Case Presentation: We present a case of a female patient with a chief complaint of headache, unilateral hearing loss, and facial paralysis. Imaging studies demonstrated a mass in the left temporal bone. Intraoperatively, several hard, blood-stained fragments of bone and soft tissue. A complete microsurgical removal was achieved through a transmastoid-translabyrinthine approach with a preserved dura. Histopathological analysis confirmed the diagnosis of endolymphatic sac tumor. The patient was discharged with no new neurological deficit after the surgery with OPD follow up and referral for genetic studies. Conclusion: The reported case showed an unusual pre- and intraoperative presentation of endolymphatic sac tumor necessitating the need for early identification of such cases. Complete microsurgical removal remains the mainstay of treatment. Endolymphatic sac tumor Temporal bone tumor Facial nerve palsy Hearing loss Skull base surgery Case report Neurotology Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Endolymphatic sac tumors (ELSTs) are uncommon tumors, with about just over 300 cases documented globally ( 1 ). In 1989, Heffner first defined endolymphatic sac tumors (ELSTs) as low-grade adenocarcinomas that originate from the endolymphatic sac epithelium ( 2 ), but were subsequently categorized as ELSTs in 1993 ( 3 ). These tumors could be isolated or linked to Von Hippel-Lindau (VHL) syndrome ( 1 , 4 ). Approximately 4–16% of individuals with von Hippel–Lindau (VHL) disease have endolymphatic sac tumors (ELSTs), while in about one-third of ELSTs, have coexistence von Hippel–Lindau (VHL) disease ( 3 , 5 ). Retinal hemangioblastomas, central nervous system hemangioblastomas, renal cell carcinoma, and pheochromocytomas are also among the neoplasms that are predisposed to in von Hippel–Lindau (VHL) disease ( 6 ). The endolymphatic sac, situated on the posteromedial surface of the temporal bone, is derived from the neuroectoderm during embryonic development ( 3 ). Although ELSTs have a low-grade histological appearance, they exhibit aggressive local behavior ( 4 , 7 ). ELSTs originate in the base of the skull and often extend to the posterior petrous bone, the mastoid, the semicircular canal, the cerebellopontine angle structures, and the cranial nerves ( 1 , 8 ). ELSTs usually present as hearing loss and neuropathy, depending on brain involvement ( 7 ). Tinnitus, vertigo, and fluctuating hearing loss are commonly reported symptoms ( 9 ). The best imaging method for ELST is contrast-enhanced MRI, which, because of its hypervascular character, usually shows a heterogeneous hyperintense mass on contrast-enhanced T1 and T2-weighted sequences, and MRI can be used to differentiate Meniere's disease from ELST, hence the primary differential diagnosis. However, the diagnosis is confirmed by histopathological examination ( 7 , 9 , 10 ). Macroscopically, endolymphatic sac tumors (ELSTs) are typically reddish-brown or reddish-blue, highly vascular lesions with often soft to moderately firm/fibrous ( 8 , 11 , 12 ). While microscopically, the tumor exhibited a papillary and glandular pattern with cystic areas, demonstrating an invasive growth behavior associated with destruction of the petrous portion of the temporal bone ( 8 , 13 , 14 ). Complete surgical resection is the main treatment for endolymphatic sac tumors, intending to remove the tumor while maintaining neurological function ( 7 , 15 ). Endolymphatic sac tumors (ELSTs) are rare and often present with nonspecific auditory and vestibular symptoms, which can delay diagnosis. Reporting this case highlights an atypical presentation, and Intraoperative findings emphasize the importance of timely diagnosis and optimal surgical planning. Case Presentation A 42-year-old female who was previously healthy presentedto the neurology department with a primary complaint of headache, mainly migraine, accompanied by nausea and vomiting. Additionally, she reported slowly progressive left facial weakness. During the neurological examination, there was a grade VI House-Brackmann facial nerve paralysis. At that time, there was also a progression of hearing loss; therefore, referred to neurotology and the lateral skull base clinic. During her first evaluation at theneurotology and lateral skull base clinic. The patient reported there was a left ear reduction in hearing sense with intermittent bloody ear discharge. A comprehensive ear, nose, throat, larynx, and head and neck examination revealed only granulation tissue protruding from the left tympanic membrane and mixed with purulent discharge, with complete (grade VI) facial nerve palsy. A clinical hearing assessment showed a negative Rinne’s test and lateralization to the right ear during the Weber’s test, which was consistent with SNHL type. A pure tone audiometry was requested to quantify the hearing loss level and to confirm the hearing loss type. PTA results showed profound SNHL in the left ear with a normal hearing level in the right ear. Additionally, tympanometry showed bilateral type A curves. Based on these clinical findings, imaging modalities such as a CT scan and MRI were warranted for further evaluation. A CT scan of the temporal bone, as shown in [Figure 1 ], demonstrates features suggestive of a neoplastic process involving the petrous part of the left temporal bone. Following the CT Scan findings, a further MRI with Gadolinium contrast was obtained for better visualization of the lesion. The study revealed findings suggestive of a left-sided endolymphatic sac tumor infiltrating the internal auditory canal, involving the vestibulocochlear nerve (CN VIII) and the tympanic segment of the facial nerve (CN VII), as well as the interosseous component of the glossopharyngeal nerve (CN IX), as shown in [Figure 2 ]. The patient was given the option of surgical removal of the tumor to relieve her symptoms. A multidisciplinary team, including a skull-base surgeon, collaborated with the neurosurgery department to plan the surgery. Thereafter, the patient underwent surgical resection of the tumor via a transmastoid-translabyrinthine approach. Intraoperatively, an interesting finding was noted that the lesion grossly consisted of firm bony fragments intermixed with soft tissues, demonstrating a spongiform appearance with bloody-stained surfaces and easily fragmenting and bleeding with micro manipulation and dissection, as better visualized in [Figure 3 ]. Extradural intracranial total resection of the tumor from the tentorium and cerebellum with careful dissection and released from the great vessels and other cranial nerves. The facial nerve was totally damaged by tumor expansion from the cerebellopontine angle to the distal end of the mastoid part. As well as the cochleovestibular nerve. Fibrin glue and fat were applied as obliteration with a rotation Palva musculoperiosteal flap over it. The resected specimen was sent for histopathological analysis, and the findings of the histopathological examination of the lesion confirmed the diagnosis of endolymphatic sac tumor, as described in [Figure 4 ]. Following surgery, the patient was successfully extubated and sent to the intensive care unit (ICU) for observation. She was then sent home in stable condition with a genetic referral for a von Hippel-Lindau (VHL) disease study and follow-up. Literature Review A review of the relevant literature identified 15 cases of endolymphatic sac tumor and summarized them in Table 1 . The ages of these cases range from 4 to 63 years old, with a mean age of 36 years. There was a clear female predominance with 11 females compared to 5 males. At the same time, our patient is a 42-year-old. The most frequent presenting symptoms in the reviewed literature were hearing loss, which was reported in 87% of the cases (13 out of 15). Our patient was presenting with co-existing migraine-type headache and facial nerve weakness. In comparison to our case, facial nerve involvement was also documented in about 67% (10 out of 15 cases). Other reported cases are often accompanied by tinnitus and vertigo. Regarding the audiological profile, our case presented with profound SNHL, similar to findings in about one-third of the reported cases. Laterality was found predominantly on the left side among 10 cases. Our presenting case was also noted as left-sided, consistent with the presenting literature. On histopathological examination, almost all cases demonstrated papillary structures, which are typical of endolymphatic sac tumor. Our patient’s analysis was also similar to the reported cases and confirming the diagnosis. In contrast, the gross appearance of our patient’s tumor was similar to only 2 out of the 15 previously reported cases that described the presence of bony fragments, whereas the majority of other cases reported highly vascular tumors. Regarding management, almost all reported cases underwent surgical excision. Some required preoperative embolization or postoperative radiotherapy, especially when subtotal resection was achieved. Our presenting case was treated with a combined transmastoid–translabyrinthine approach and complete excision, without the need for adjuvant therapy. In summary, our case aligns with previously reported patterns in terms of sex, tumor laterality, hearing profile, and facial nerve involvement, but demonstrates atypical intraoperative findings compared to most cases. Table 1 Summary of the Present Case and the Other 15 Reported Cases of Endolymphatic Sac Tumor. Author., Year Age Sex Country Initial Presentation Audiological Profile Facial (7th ) Nerve Side Histopathology Gross Appearance (Intraoperative Findings) Treatment Present Case 42 F Saudi Arabia Migraine-Type Headache, Facial Weakness, and Hearing Loss Profound SNHL Involved L Papillary Structures Consistent with ELST Multiple Fragments of Hard Bone and Soft Tissue, which are Firm and Blood-Stained Surgical Excision with Trans-mastoid and Trans-labyrinthine Approaches Davoodi et al., 2023 15 F Iran Facial Weakness and Hearing Loss No Data Involved R Papillary Tumor Consistent with ELST No Data Surgical Excision with Trans-mastoid and Trans-labyrinthine Approaches Mezri et al., 2025 34 M Tunisia Hearing Loss, Tinnitus, and Vertigo Profound SNHL Intact R Papillary Endolymphatic Sac Tumor Highly Vascular Tumor Surgical excision with a retro-labyrinthine approach Nacheva et al., 2025 36 F Bulgaria Vertigo and Tinnitus Mild to Moderate SNHL Intact L Papillary Endolymphatic Sac Tumor Appeared Yellowish in Color and Solid in Consistency Sub-occipital Retro-sigmoid Approach Yuan et al., 2025 53 M China Dizziness and Blurring Vision Moderate SNHL Intact L Papillary, Glandular Pattern Suggesting Inner Ear Lymphocytoma Highly Vascular with Greyish-Red Appearance Distal Lateral Combined Anterior Approach to the Sigmoid Sinus and Post-Operative Radiotherapy Sun et al., 2012 31 M China Hearing Loss and Headache No Data Intact L Papillary, Cystic or Glandular Architecture Consistent with ELST Pale/Pink Appearance with Moderate Consistency Surgical Excision and Post-Operative Radiotherapy Ge et al., 2020 47 M China Hearing Loss and Headache No Data Involved R Papillary Arrangement Consistent with ELST No Data A Ventriculoperitoneal Shunt, combined with a Local Biopsy and Post-Operative Radiotherapy Kumar et al., 2009 24 F USA Hearing Loss No Data Involved L Papillary Fronds Consistent with ELST No Data Surgical Excision* Liu et al., 2020 38 F China Vertigo, Hearing Loss, and Tinnitus Moderate SNHL Intact R Consistent with ELST No Data Surgical Excision* Reijneveld et al., 1997 63 F Netherlands Hearing Loss, Facial Weakness, Imbalance, and Ataxia No Data Involved L Initial Diagnoses Varied, But Histologic Review Confirmed ELST From the First Surgery. No Data Subtotal Surgical Excision Villegas-González et al., 2022 24 M Mexico Hearing Loss and Tinnitus Mild to Moderate SNHL Intact L Papillary Structures with Fibrovascular Bundles Consistent with ELST No Data Surgical Excision with Trans-mastoid and Trans-labyrinthine Approaches Yilmaz et al., 2008 22 F Turkey Long-standing Facial Weakness, Hearing Loss, and Hoarseness No Data Involved L Papillary Pattern and Scattered Follicular Structures Consistent with ELST No Data Endovascular Embolization, Surgical Excision with Trans-mastoid and Trans-labyrinthine Approaches Rajeshwari et al., 2019 63 F India Facial Weakness No Data Involved L Papillary Tumor Consistent with ELST Grey White to Grey Brown Soft Tissue with Bony Fragments Pre-Operative Embolization and Surgical Excision Daniel et al., 2022 33 F Brazil Headache, Imbalance, Hearing Loss, and Facial Weakness No Data Involved L Neoplasm with a Papillary Pattern Consistent with ELST No Data Surgical Excision with Trans-labyrinthine Approach Yu et al., 2011 25 F China Hearing Loss, Facial Weakness, and Mandibular Numbness No Data Involved R Papillary Structures Consistent with ELST No Data Subtotal Surgical Excision with Trans-mastoid Approach and Post-Operative Radiotherapy Kupferman et al., 2004 4 M USA Serous Otitis Media and Facial Weakness Profound SNHL Involved R Confirmed the Diagnosis with ELST No Data Surgical Excision with Trans-Temporal and Trans-Cochlear Approaches, Facial Nerve Decompression M; Male, F; Female, R; Right Side, L; Left Side, *No Data Regarding the Surgical Approach Used Discussion Endolymphatic Sac Tumors (ELSTs) are rare epithelial neoplasms arising from the endolymphatic duct and sac, and it is characterized by their richly vascular interstitium and their distinctive papillary and glandular tubular architecture. Although histologically benign and slow-growing, they are locally aggressive lesions of the temporal bone that can cause significant destruction of adjacent structures (8,14). This tumor often manifests as a sporadic growth; however, in up to 30% of those afflicted, it coexists with von Hippel-Lindau (VHL) disease ( 5 ). Genetic and molecular analyses of VHL disease–associated endolymphatic sac tumors (ELSTs) have demonstrated that their mutations closely resemble those identified in other neoplasms related to VHL disease ( 23 ). ELSTs have been documented across a broad age range, with most cases typically diagnosed during the fifth and sixth decades, aligning with our patient’s age of 42 years—slightly younger than average but still within the reported spectrum ( 7 , 24 , 25 ). However, this contrasts with findings from our reviewed literature [Table 1 ], which includes younger presentations; for example, Kupferman et al. reported a case in a 4-year-old boy, and Davoodi et al. described another in a 15-year-old female ( 7 , 22 ). In our analysis [Table 1 ], the majority of cases occurred during the second and third decades of life, underscoring the variability in age at diagnosis. Sporadic forms, in particular, tend to manifest around the fifth decade ( 7 ). However, in cases associated with VHL disease, the tumor tends to appear at a younger age, is female predominant, and may involve both sides in up to one-third of patients ( 25 , 26 ). There are no significant gender differences reported in the overall occurrence of sporadic ELSTs, as both males and females appear to be equally affected according to most studies ( 14 ). However, in our reviewed literature [Table 1 ], we observed a slight female predominance, suggesting that gender distribution may vary across different study populations or sample sizes. The symptoms are often nonspecific, making early diagnosis uncommon ( 27 ). The typical clinical presentation includes audiovestibular symptoms such as progressive sensorineural hearing loss, vertigo, ataxia, and tinnitus, often accompanied by varying degrees of facial nerve paralysis in one third of patients, as observed in our case and similar reports in the literature [Table 1 ], which places Ménière’s disease (Idiopathic Endolymphatic Hydrops) as the leading differential diagnosis. ( 14 , 24 , 26 ). This is thought to result from tumor growth, which applies pressure on neighboring auditory tissues or causes endolymphatic edema ( 14 , 28 ). However, our patient initially presented with an uncommon symptom — migraine headache. More interestingly, Yuan et al. reported a patient who initially presented with blurred vision ( 14 ). Therefore, the intensity of symptoms is reliant upon the location and magnitude of the impacted brain tissue ( 14 , 29 ). Imaging modalities such as CT and MRI are essential for diagnosing these tumors, as they can reveal a characteristic soft-tissue lesion within the temporal bone with associated bony erosion and possible extension into adjacent structures (7,14). A distinguishing feature of endolymphatic sac tumors (ELSTs) is that they are highly vascular tumors, and their primary arterial supply arises from branches of the external carotid artery system ( 14 ). Early ELSTs commonly affect the sigmoid sinus, medial mastoid, and internal auditory canal, while advanced tumors may extend to the jugular foramen, posterior fossa dura, and middle cranial fossa ( 7 ). However, as noted in the literature [Table 1 ], despite characteristic clinical and radiological findings, differentiating ELST from other temporal bone lesions remains challenging. Therefore, histopathological examination remains the definitive method for confirming the diagnosis ( 5 , 7 , 14 , 27 , 30 ). ELSTs are low-grade papillary adenocarcinomas that were previously often mistaken for middle ear carcinomas or ceruminous gland tumors ( 27 ). From a pathological standpoint, endolymphatic sac tumors (ELSTs) usually appear as soft, polypoid masses ranging in color from red to dark purple and are typically papillary and cystic adenoid ( 31 ). Microscopically, the surface is lined by a single layer of cuboidal or flattened epithelial cells, while the underlying mesenchymal areas are highly vascular and may contain colloid-like cystic spaces ( 8 , 13 ). As observed in our case and in nearly all reported cases in the literature, as summarized in [Table 1 ]. Immunohistochemical analysis in our case revealed strong, diffuse positivity for cytokeratin AE1/AE3 and CK7. Moreover, they may occasionally contain bone fragments, as noted in our case [Table 1 ], where multiple firm, blood-stained fragments of hard bone and soft tissue were identified intraoperatively ( 14 ). Comparable observations have also been described by Nacheva et al. and Rajeshwari et al., respectively ( 9 , 20 ). Microsurgery remains the cornerstone of treatment, aiming to achieve complete tumor removal while maximizing preservation of the patient’s hearing and facial nerve function ( 7 , 14 , 15 ). However, some cases reported in [Table 1 ], such as those by Reijneveld et al. and Yu et al., involved incomplete tumor removal due to factors such as excessive intraoperative bleeding, prolonged surgical duration, or the presence of very large tumors ( 13 , 18 ). Postoperative radiation may be necessary for certain cancers, though this is still subject to debate ( 32 ). In the latter case, postoperative radiotherapy was administered. Additionally, postoperative radiation was administered to other reported cases in [Table 1 ]. Furthermore, preoperative embolization may be used for highly vascularized tumors ( 33 ). As seen in cases reported by both Rajeshwari et al. and Yilmaz et al. ( 5 , 20 ). In conclusion, endolymphatic sac tumors are rare with local aggressive behavior. In our reporting case, the patient initially presented to the neurology department and was subsequently referred to us, where the diagnosis was established. Intraoperatively, the mass exhibited an atypical spongiform appearance with associated bony fragments. The excised mass was sent for histopathological examination, which confirmed the diagnosis of endolymphatic sac tumor. Declarations Consent for Publication Written informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal. Conflict of interest The authors have no financial relationships or conflicts of interest relevant to this article to disclose. Research Participant This study involves human participants. Source of Funding There was no source of funding for this work. Author contributions All authors contributed equally. Acknowledgments The authors would like to thank the patient for his cooperation and agree to publish the case. References Talukdar R, Epari S, Sahay A, Choudhari A, Dasgupta A, Chatterjee A et al (2022) Endolymphatic sac tumor: single-institution series of seven cases with updated review of literature. Eur Arch Oto-Rhino-Laryngology [Internet]. ;279(5):2591–8. Available from: https://doi.org/10.1007/s00405-021-07047-2 Batsakis JG, el-Naggar AK (1993) Papillary neoplasms (Heffner’s tumors) of the endolymphatic sac. 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Supplementary Files CAREChecklistWORDfile.docx Cite Share Download PDF Status: Under Review Version 1 posted Reviews received at journal 17 Apr, 2026 Reviewers agreed at journal 30 Mar, 2026 Reviews received at journal 03 Feb, 2026 Reviewers agreed at journal 27 Jan, 2026 Reviewers invited by journal 27 Jan, 2026 Editor assigned by journal 04 Dec, 2025 Submission checks completed at journal 04 Dec, 2025 First submitted to journal 02 Dec, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8264102","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":581465173,"identity":"12c39552-ae29-4e44-83de-79bcafcc1b03","order_by":0,"name":"Tawfiq Khurayzi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA8UlEQVRIie3QMQrCMBSA4RcCcUnt2uLgGbI4qb1KQ6GTri4OVoS61L0i6Blc6qoIuhQv0KWTm9gu4mhaERQhdXTIPz1CPngJgEr1h1lbgMwWg0HxoTwhtQpCAFD4JMQFEBPBvxAoCW2VBCpJLWZeOug2zSC+pfk9atYxoCzvSQjtMc8+OWyhzTYstBPmY8DmPJIt1t+k3MdoqWtRg9oJEoRgTUb0y9rj/sha6vRcEKuaGP2C7PlCC0hB+A/kmou3HJ15cGiZoZs4YsmJ/C26y8f3wbATxs7ZyNpJZzWd7LJcQl6f8B7yqu5/EZVKpVJ99gCJHkzPl0StFgAAAABJRU5ErkJggg==","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":true,"prefix":"","firstName":"Tawfiq","middleName":"","lastName":"Khurayzi","suffix":""},{"id":581465174,"identity":"79fc81a3-1167-4b5c-b04b-67a4c45ec955","order_by":1,"name":"Faisal Hakami","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Faisal","middleName":"","lastName":"Hakami","suffix":""},{"id":581465175,"identity":"748f1036-f1f8-4651-9b55-e2d1d375f38f","order_by":2,"name":"Hassan Ghafiry","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hassan","middleName":"","lastName":"Ghafiry","suffix":""},{"id":581465176,"identity":"36634481-7628-4aa2-adac-cf766f0ab9e3","order_by":3,"name":"Amir Gazali","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Amir","middleName":"","lastName":"Gazali","suffix":""},{"id":581465177,"identity":"197a6a56-211b-44ef-a58b-f0d5450f255e","order_by":4,"name":"Sameeh Al-Gassmi","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Sameeh","middleName":"","lastName":"Al-Gassmi","suffix":""},{"id":581465178,"identity":"cc9b4861-7872-43bc-a497-42dd867547ff","order_by":5,"name":"Meshal Jarebi","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Meshal","middleName":"","lastName":"Jarebi","suffix":""},{"id":581465179,"identity":"f5a3d1ba-5f2e-481e-8cac-2e47218286ed","order_by":6,"name":"Ali Kamili","email":"","orcid":"","institution":"King Fahad Central Hospital","correspondingAuthor":false,"prefix":"","firstName":"Ali","middleName":"","lastName":"Kamili","suffix":""}],"badges":[],"createdAt":"2025-12-02 21:08:03","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8264102/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8264102/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":101459971,"identity":"11bd0dcd-5fd7-4151-a054-9453e1c4c373","added_by":"auto","created_at":"2026-01-30 01:35:33","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":150939,"visible":true,"origin":"","legend":"\u003cp\u003eAn Axial (A) and Coronal (B) Cuts, Bone Window CT-Scan of the Left Temporal Bone; demonstrating lytic lesion given a moth-eaten appearance destructing the posterior aspect of the petrous part of the left temporal bone involving the vestibular aqueduct, semicircular canals, the facial nerve canal, jugular foramen (mainly pars vascularis) and to lesser extent the internal auditory canal, small extension to the middle ear cavity also noted.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/95fb5bb1ef927941bc7b2881.png"},{"id":101752051,"identity":"5ac5ccf2-136f-47b6-9d2a-50ae150d869e","added_by":"auto","created_at":"2026-02-03 10:25:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":233372,"visible":true,"origin":"","legend":"\u003cp\u003eBoth Axial (A-C) and Coronal (B-D) Cuts on Both T1 (A-B) and T2 (C-D); Demonstrating left-sided mass eroding and invading the retro-labyrinthine portion of the left temporal bone, involving part of the jugular foramen, extra axial lesion without promoting thrombosis of venous sinuses. It is high-intensity T1, heterogeneous signal in T2 post contrast enhancement in non-cystic component infiltrating the tympanic segment of facial nerve, saccule and utricle, vestibule and vestibular aqueduct separate from cochlea, and infiltrate the medial, lateral, and partially superior semicircular canal, infiltrating and causing narrowing the internal auditory canal which involving the VIII nerve as well as the interosseous component of IX nerve, extending down to the mastoid air cells, consistent with endolymphatic sac tumor.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/f2a63c1347893178f46bd411.png"},{"id":101751627,"identity":"968b0521-02fb-4efc-b0f0-cd25a01cdbc1","added_by":"auto","created_at":"2026-02-03 10:21:53","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":303985,"visible":true,"origin":"","legend":"\u003cp\u003eDemonstrates Intraoperative Findings Using an Operating Microscope. Figure A shows the view during Mastoidectomy, while Figure B is more magnified after further drilling for better visualization. In Figures A and B, the black asterisk illustrates the posterior external auditory canal wall, and the white asterisk indicates the Tegmen Mastoidum. The tumor is identified in Figure A (white circle) with a spongiform appearance, while in Figure B (white oval-shaped), the same tumor after drilling is shown under magnification and appears blood-stained. The black arrowhead in Figure A points to the posterior cranial fossa. The black arrow in Figure B indicates the facial nerve. The white arrow in Figure B shows the dura.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/5bdd3edf667bfe9ab6d04247.png"},{"id":101459974,"identity":"3b6c5d04-8472-4c1b-be0a-624f8f5a5ec4","added_by":"auto","created_at":"2026-01-30 01:35:33","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":757057,"visible":true,"origin":"","legend":"\u003cp\u003ehistology shows a neoplasm with papillary architecture (*) and some hyalinized septae with entrapped bone trabeculae (arrow). The papillae are lined by columnar cells with uniform, bland nuclei (arrowhead). Figure 4A shows H\u0026amp;E at 5.0X. Figure 4B shows H\u0026amp;E at 20.0X. Figure 4D shows H\u0026amp;E at 40.0X. In Figure 4C, immunohistochemistry (IHC) is positive for CK (AE1-AE3) at 10.0X. It is also positive for CK18.8 and CK7 but negative for CK20, CD10, S100, and Vimentin immunostains.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/485a02a992a5ec6716a52887.png"},{"id":101756293,"identity":"3555e3e6-f0a8-4818-bbf3-a508087ddec1","added_by":"auto","created_at":"2026-02-03 10:57:23","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2069568,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/3ab2b961-0e1a-4db1-ab0e-62b740c99a23.pdf"},{"id":101459973,"identity":"b32fe5f6-cc7c-4b2b-ac4f-2582c33290c9","added_by":"auto","created_at":"2026-01-30 01:35:33","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":32850,"visible":true,"origin":"","legend":"","description":"","filename":"CAREChecklistWORDfile.docx","url":"https://assets-eu.researchsquare.com/files/rs-8264102/v1/8b7be6088a9a03e3e8fcae8f.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Unusual Endolymphatic Sac Tumor: Case Report and Literature Review","fulltext":[{"header":"Introduction","content":"\u003cp\u003eEndolymphatic sac tumors (ELSTs) are uncommon tumors, with about just over 300 cases documented globally (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). In 1989, Heffner first defined endolymphatic sac tumors (ELSTs) as low-grade adenocarcinomas that originate from the endolymphatic sac epithelium (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e), but were subsequently categorized as ELSTs in 1993 (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThese tumors could be isolated or linked to Von Hippel-Lindau (VHL) syndrome (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). Approximately 4\u0026ndash;16% of individuals with von Hippel\u0026ndash;Lindau (VHL) disease have endolymphatic sac tumors (ELSTs), while in about one-third of ELSTs, have coexistence von Hippel\u0026ndash;Lindau (VHL) disease (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Retinal hemangioblastomas, central nervous system hemangioblastomas, renal cell carcinoma, and pheochromocytomas are also among the neoplasms that are predisposed to in von Hippel\u0026ndash;Lindau (VHL) disease (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe endolymphatic sac, situated on the posteromedial surface of the temporal bone, is derived from the neuroectoderm during embryonic development (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Although ELSTs have a low-grade histological appearance, they exhibit aggressive local behavior (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). ELSTs originate in the base of the skull and often extend to the posterior petrous bone, the mastoid, the semicircular canal, the cerebellopontine angle structures, and the cranial nerves (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eELSTs usually present as hearing loss and neuropathy, depending on brain involvement (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). Tinnitus, vertigo, and fluctuating hearing loss are commonly reported symptoms (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). The best imaging method for ELST is contrast-enhanced MRI, which, because of its hypervascular character, usually shows a heterogeneous hyperintense mass on contrast-enhanced T1 and T2-weighted sequences, and MRI can be used to differentiate Meniere's disease from ELST, hence the primary differential diagnosis. However, the diagnosis is confirmed by histopathological examination (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Macroscopically, endolymphatic sac tumors (ELSTs) are typically reddish-brown or reddish-blue, highly vascular lesions with often soft to moderately firm/fibrous (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). While microscopically, the tumor exhibited a papillary and glandular pattern with cystic areas, demonstrating an invasive growth behavior associated with destruction of the petrous portion of the temporal bone (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eComplete surgical resection is the main treatment for endolymphatic sac tumors, intending to remove the tumor while maintaining neurological function (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eEndolymphatic sac tumors (ELSTs) are rare and often present with nonspecific auditory and vestibular symptoms, which can delay diagnosis. Reporting this case highlights an atypical presentation, and Intraoperative findings emphasize the importance of timely diagnosis and optimal surgical planning.\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eA 42-year-old female who was previously healthy presentedto the neurology department with a primary complaint of headache, mainly migraine, accompanied by nausea and vomiting. Additionally, she reported slowly progressive left facial weakness. During the neurological examination, there was a grade VI House-Brackmann facial nerve paralysis. At that time, there was also a progression of hearing loss; therefore, referred to neurotology and the lateral skull base clinic.\u003c/p\u003e \u003cp\u003eDuring her first evaluation at theneurotology and lateral skull base clinic. The patient reported there was a left ear reduction in hearing sense with intermittent bloody ear discharge. A comprehensive ear, nose, throat, larynx, and head and neck examination revealed only granulation tissue protruding from the left tympanic membrane and mixed with purulent discharge, with complete (grade VI) facial nerve palsy. A clinical hearing assessment showed a negative Rinne’s test and lateralization to the right ear during the Weber’s test, which was consistent with SNHL type.\u003c/p\u003e \u003cp\u003eA pure tone audiometry was requested to quantify the hearing loss level and to confirm the hearing loss type. PTA results showed profound SNHL in the left ear with a normal hearing level in the right ear. Additionally, tympanometry showed bilateral type A curves.\u003c/p\u003e \u003cp\u003eBased on these clinical findings, imaging modalities such as a CT scan and MRI were warranted for further evaluation. A CT scan of the temporal bone, as shown in [Figure \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], demonstrates features suggestive of a neoplastic process involving the petrous part of the left temporal bone. Following the CT Scan findings, a further MRI with Gadolinium contrast was obtained for better visualization of the lesion. The study revealed findings suggestive of a left-sided endolymphatic sac tumor infiltrating the internal auditory canal, involving the vestibulocochlear nerve (CN VIII) and the tympanic segment of the facial nerve (CN VII), as well as the interosseous component of the glossopharyngeal nerve (CN IX), as shown in [Figure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe patient was given the option of surgical removal of the tumor to relieve her symptoms. A multidisciplinary team, including a skull-base surgeon, collaborated with the neurosurgery department to plan the surgery.\u003c/p\u003e \u003cp\u003eThereafter, the patient underwent surgical resection of the tumor via a transmastoid-translabyrinthine approach. Intraoperatively, an interesting finding was noted that the lesion grossly consisted of firm bony fragments intermixed with soft tissues, demonstrating a spongiform appearance with bloody-stained surfaces and easily fragmenting and bleeding with micro manipulation and dissection, as better visualized in [Figure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e]. Extradural intracranial total resection of the tumor from the tentorium and cerebellum with careful dissection and released from the great vessels and other cranial nerves. The facial nerve was totally damaged by tumor expansion from the cerebellopontine angle to the distal end of the mastoid part. As well as the cochleovestibular nerve. Fibrin glue and fat were applied as obliteration with a rotation Palva musculoperiosteal flap over it.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe resected specimen was sent for histopathological analysis, and the findings of the histopathological examination of the lesion confirmed the diagnosis of endolymphatic sac tumor, as described in [Figure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e]. Following surgery, the patient was successfully extubated and sent to the intensive care unit (ICU) for observation. She was then sent home in stable condition with a genetic referral for a von Hippel-Lindau (VHL) disease study and follow-up.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e\u003c/p\u003e \u003c/div\u003e"},{"header":"Literature Review","content":"\u003cp\u003eA review of the relevant literature identified 15 cases of endolymphatic sac tumor and summarized them in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The ages of these cases range from 4 to 63 years old, with a mean age of 36 years. There was a clear female predominance with 11 females compared to 5 males. At the same time, our patient is a 42-year-old.\u003c/p\u003e\u003cp\u003eThe most frequent presenting symptoms in the reviewed literature were hearing loss, which was reported in 87% of the cases (13 out of 15). Our patient was presenting with co-existing migraine-type headache and facial nerve weakness. In comparison to our case, facial nerve involvement was also documented in about 67% (10 out of 15 cases). Other reported cases are often accompanied by tinnitus and vertigo. Regarding the audiological profile, our case presented with profound SNHL, similar to findings in about one-third of the reported cases.\u003c/p\u003e\u003cp\u003eLaterality was found predominantly on the left side among 10 cases. Our presenting case was also noted as left-sided, consistent with the presenting literature.\u003c/p\u003e\u003cp\u003eOn histopathological examination, almost all cases demonstrated papillary structures, which are typical of endolymphatic sac tumor. Our patient’s analysis was also similar to the reported cases and confirming the diagnosis. In contrast, the gross appearance of our patient’s tumor was similar to only 2 out of the 15 previously reported cases that described the presence of bony fragments, whereas the majority of other cases reported highly vascular tumors.\u003c/p\u003e\u003cp\u003eRegarding management, almost all reported cases underwent surgical excision. Some required preoperative embolization or postoperative radiotherapy, especially when subtotal resection was achieved. Our presenting case was treated with a combined transmastoid–translabyrinthine approach and complete excision, without the need for adjuvant therapy.\u003c/p\u003e\u003cp\u003eIn summary, our case aligns with previously reported patterns in terms of sex, tumor laterality, hearing profile, and facial nerve involvement, but demonstrates atypical intraoperative findings compared to most cases.\u003c/p\u003e\u003cdiv class=\"gridtable\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSummary of the Present Case and the Other 15 Reported Cases of Endolymphatic Sac Tumor.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e\u003ccolgroup cols=\"11\"\u003e\u003c/colgroup\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAuthor., Year\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSex\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eCountry\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eInitial Presentation\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAudiological Profile\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eFacial (7th ) Nerve\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eSide\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eHistopathology\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eGross Appearance (Intraoperative Findings)\u003c/p\u003e \u003c/th\u003e\u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePresent Case\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSaudi Arabia\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMigraine-Type Headache, Facial Weakness, and Hearing Loss\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eProfound SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Structures Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eMultiple Fragments of Hard Bone and Soft Tissue, which are Firm and Blood-Stained\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision with Trans-mastoid and Trans-labyrinthine Approaches\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDavoodi et al., 2023\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eIran\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFacial Weakness and Hearing Loss\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Tumor Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision with Trans-mastoid and Trans-labyrinthine Approaches\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMezri et al., 2025\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTunisia\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss, Tinnitus, and Vertigo\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eProfound SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Endolymphatic Sac Tumor\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eHighly Vascular Tumor\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical excision with a retro-labyrinthine approach\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNacheva et al., 2025\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e36\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBulgaria\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertigo and Tinnitus\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMild to Moderate SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Endolymphatic Sac Tumor\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eAppeared Yellowish in Color and Solid in Consistency\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSub-occipital Retro-sigmoid Approach\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYuan et al., 2025\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e53\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eDizziness and Blurring Vision\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eModerate SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary, Glandular Pattern Suggesting Inner Ear Lymphocytoma\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eHighly Vascular with Greyish-Red Appearance\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eDistal Lateral Combined Anterior Approach to the Sigmoid Sinus and Post-Operative Radiotherapy\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSun et al., 2012\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e31\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss and Headache\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary, Cystic\u003c/p\u003e \u003cp\u003eor Glandular Architecture Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003ePale/Pink Appearance with Moderate Consistency\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision and Post-Operative Radiotherapy\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGe et al., 2020\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss and Headache\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Arrangement Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eA Ventriculoperitoneal Shunt, combined with a Local Biopsy and Post-Operative Radiotherapy\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKumar et al., 2009\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eUSA\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Fronds Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision*\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLiu et al., 2020\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e38\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eVertigo, Hearing Loss, and Tinnitus\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eModerate SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eConsistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision*\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReijneveld et al., 1997\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNetherlands\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss, Facial Weakness, Imbalance, and Ataxia\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eInitial Diagnoses Varied, But Histologic Review Confirmed ELST From the First Surgery.\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSubtotal Surgical Excision\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVillegas-González et al., 2022\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMexico\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss and Tinnitus\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eMild to Moderate SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eIntact\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Structures with Fibrovascular Bundles Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision with Trans-mastoid and Trans-labyrinthine Approaches\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYilmaz et al., 2008\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eTurkey\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eLong-standing Facial Weakness, Hearing Loss, and Hoarseness\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Pattern and Scattered Follicular Structures Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eEndovascular Embolization, Surgical Excision with Trans-mastoid and Trans-labyrinthine Approaches\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRajeshwari et al., 2019\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eIndia\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eFacial Weakness\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Tumor Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eGrey White to Grey Brown Soft Tissue with Bony Fragments\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003ePre-Operative Embolization and Surgical Excision\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDaniel et al., 2022\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e33\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBrazil\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHeadache, Imbalance, Hearing Loss, and Facial Weakness\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eNeoplasm with a Papillary Pattern Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision with Trans-labyrinthine Approach\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYu et al., 2011\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eChina\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHearing Loss, Facial Weakness, and Mandibular Numbness\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePapillary Structures Consistent with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSubtotal Surgical Excision with Trans-mastoid Approach and Post-Operative Radiotherapy\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eKupferman et al., 2004\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eUSA\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eSerous Otitis Media and Facial Weakness\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eProfound SNHL\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eInvolved\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eConfirmed the Diagnosis with ELST\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003eNo Data\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eSurgical Excision with Trans-Temporal and Trans-Cochlear Approaches, Facial Nerve Decompression\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"11\" nameend=\"c11\" namest=\"c1\"\u003e \u003cp\u003eM; Male, F; Female, R; Right Side, L; Left Side, *No Data Regarding the Surgical Approach Used\u003c/p\u003e \u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/table\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eEndolymphatic Sac Tumors (ELSTs) are rare epithelial neoplasms arising from the endolymphatic duct and sac, and it is characterized by their richly vascular interstitium and their distinctive papillary and glandular tubular architecture. Although histologically benign and slow-growing, they are locally aggressive lesions of the temporal bone that can cause significant destruction of adjacent structures (8,14).\u003c/p\u003e \u003cp\u003eThis tumor often manifests as a sporadic growth; however, in up to 30% of those afflicted, it coexists with von Hippel-Lindau (VHL) disease (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). Genetic and molecular analyses of VHL disease\u0026ndash;associated endolymphatic sac tumors (ELSTs) have demonstrated that their mutations closely resemble those identified in other neoplasms related to VHL disease (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eELSTs have been documented across a broad age range, with most cases typically diagnosed during the fifth and sixth decades, aligning with our patient\u0026rsquo;s age of 42 years\u0026mdash;slightly younger than average but still within the reported spectrum (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e). However, this contrasts with findings from our reviewed literature [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], which includes younger presentations; for example, Kupferman et al. reported a case in a 4-year-old boy, and Davoodi et al. described another in a 15-year-old female (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). In our analysis [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], the majority of cases occurred during the second and third decades of life, underscoring the variability in age at diagnosis. Sporadic forms, in particular, tend to manifest around the fifth decade (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). However, in cases associated with VHL disease, the tumor tends to appear at a younger age, is female predominant, and may involve both sides in up to one-third of patients (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThere are no significant gender differences reported in the overall occurrence of sporadic ELSTs, as both males and females appear to be equally affected according to most studies (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). However, in our reviewed literature [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], we observed a slight female predominance, suggesting that gender distribution may vary across different study populations or sample sizes.\u003c/p\u003e \u003cp\u003eThe symptoms are often nonspecific, making early diagnosis uncommon (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). The typical clinical presentation includes audiovestibular symptoms such as progressive sensorineural hearing loss, vertigo, ataxia, and tinnitus, often accompanied by varying degrees of facial nerve paralysis in one third of patients, as observed in our case and similar reports in the literature [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], which places M\u0026eacute;ni\u0026egrave;re\u0026rsquo;s disease (Idiopathic Endolymphatic Hydrops) as the leading differential diagnosis. (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). This is thought to result from tumor growth, which applies pressure on neighboring auditory tissues or causes endolymphatic edema (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e). However, our patient initially presented with an uncommon symptom \u0026mdash; migraine headache. More interestingly, Yuan et al. reported a patient who initially presented with blurred vision (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Therefore, the intensity of symptoms is reliant upon the location and magnitude of the impacted brain tissue (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eImaging modalities such as CT and MRI are essential for diagnosing these tumors, as they can reveal a characteristic soft-tissue lesion within the temporal bone with associated bony erosion and possible extension into adjacent structures (7,14). A distinguishing feature of endolymphatic sac tumors (ELSTs) is that they are highly vascular tumors, and their primary arterial supply arises from branches of the external carotid artery system (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Early ELSTs commonly affect the sigmoid sinus, medial mastoid, and internal auditory canal, while advanced tumors may extend to the jugular foramen, posterior fossa dura, and middle cranial fossa (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). However, as noted in the literature [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], despite characteristic clinical and radiological findings, differentiating ELST from other temporal bone lesions remains challenging. Therefore, histopathological examination remains the definitive method for confirming the diagnosis (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e). ELSTs are low-grade papillary adenocarcinomas that were previously often mistaken for middle ear carcinomas or ceruminous gland tumors (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e). From a pathological standpoint, endolymphatic sac tumors (ELSTs) usually appear as soft, polypoid masses ranging in color from red to dark purple and are typically papillary and cystic adenoid (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e). Microscopically, the surface is lined by a single layer of cuboidal or flattened epithelial cells, while the underlying mesenchymal areas are highly vascular and may contain colloid-like cystic spaces (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). As observed in our case and in nearly all reported cases in the literature, as summarized in [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e]. Immunohistochemical analysis in our case revealed strong, diffuse positivity for cytokeratin AE1/AE3 and CK7.\u003c/p\u003e \u003cp\u003eMoreover, they may occasionally contain bone fragments, as noted in our case [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], where multiple firm, blood-stained fragments of hard bone and soft tissue were identified intraoperatively (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). Comparable observations have also been described by Nacheva et al. and Rajeshwari et al., respectively (\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eMicrosurgery remains the cornerstone of treatment, aiming to achieve complete tumor removal while maximizing preservation of the patient\u0026rsquo;s hearing and facial nerve function (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e). However, some cases reported in [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e], such as those by Reijneveld et al. and Yu et al., involved incomplete tumor removal due to factors such as excessive intraoperative bleeding, prolonged surgical duration, or the presence of very large tumors (\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e). Postoperative radiation may be necessary for certain cancers, though this is still subject to debate (\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e). In the latter case, postoperative radiotherapy was administered. Additionally, postoperative radiation was administered to other reported cases in [Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e]. Furthermore, preoperative embolization may be used for highly vascularized tumors (\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e). As seen in cases reported by both Rajeshwari et al. and Yilmaz et al. (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn conclusion, endolymphatic sac tumors are rare with local aggressive behavior. In our reporting case, the patient initially presented to the neurology department and was subsequently referred to us, where the diagnosis was established. Intraoperatively, the mass exhibited an atypical spongiform appearance with associated bony fragments. The excised mass was sent for histopathological examination, which confirmed the diagnosis of endolymphatic sac tumor.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp style=\"text-align: left;\"\u003e\u003cstrong\u003eConsent for Publication\u003cspan dir=\"RTL\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eWritten informed consent was obtained from the patient for publication of this case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eConflict of interest\u003c/span\u003e\u003c/strong\u003e\u003cspan dir=\"LTR\"\u003e\u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eThe authors have no financial relationships or conflicts of interest relevant to this article to disclose.\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eResearch Participant\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eThis study involves human participants. \u0026nbsp;\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eSource of Funding\u003c/span\u003e\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eThere was no source of funding for this work.\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eAuthor contributions\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eAll authors contributed equally.\u003c/span\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cstrong\u003e\u003cspan dir=\"LTR\"\u003eAcknowledgments\u003c/span\u003e\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp dir=\"RTL\" style=\"text-align: left;\"\u003e\u003cspan dir=\"LTR\"\u003eThe authors would like to thank the patient for his cooperation and agree to publish the case.\u0026nbsp;\u003c/span\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eTalukdar R, Epari S, Sahay A, Choudhari A, Dasgupta A, Chatterjee A et al (2022) Endolymphatic sac tumor: single-institution series of seven cases with updated review of literature. Eur Arch Oto-Rhino-Laryngology [Internet]. ;279(5):2591\u0026ndash;8. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1007/s00405-021-07047-2\u003c/span\u003e\u003cspan address=\"10.1007/s00405-021-07047-2\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBatsakis JG, el-Naggar AK (1993) Papillary neoplasms (Heffner\u0026rsquo;s tumors) of the endolymphatic sac. Ann Otol Rhinol Laryngol 102(8 Pt 1):648\u0026ndash;651\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMehta GU, Kim HJ, Gidley PW, Daniels AB, Miller ME, Lekovic GP et al (2022) Endolymphatic Sac Tumor Screening and Diagnosis in von Hippel-Lindau Disease: A Consensus Statement. 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Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://dx.doi.org/10.2484/rcr.v6i3.372\u003c/span\u003e\u003cspan address=\"10.2484/rcr.v6i3.372\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLiu Y, Xie J, Ge X, Gong S (2020) [Endolymphatic sac tumor with symptoms of endolymphatic hydrops: a case report and reviews]. Lin chuang er bi yan hou tou jing wai ke za zhi\u0026thinsp;=\u0026thinsp;J. Clin Otorhinolaryngol head neck Surg 34(5):468\u0026ndash;469\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eReijneveld JC, Hanlo P, Groenewoud G, Jansen G, Van Overbeeke K, Tulleken C (1997) Endolymphatic sac tumor: A case report and review of the literature. 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Surg Neurol Int 13(510):36\u0026ndash;37\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKupferman ME, Bigelow DC, Carpentieri DF, Bilaniuk LT, Kazahaya K (2004) Endolymphatic sac tumor in a 4-year-old boy. Otol Neurotol 25(5):782\u0026ndash;786\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHoriguchi H, Sano T, Toi H, Kageji T, Hirokawa M, Nagahiro S (2001) Endolymphatic sac tumor associated with a von Hippel-Lindau disease patient: an immunohistochemical study. Mod Pathol Off J United States Can Acad Pathol Inc 14(7):727\u0026ndash;732\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchnack DT, Kiss K, Hansen S, Miyazaki H, Bech B, Caye Thomasen P (2017) Sporadic Endolymphatic Sac Tumor-A Very Rare Cause of Hearing Loss, Tinnitus, and Dizziness. J Int Adv Otol 13(2):289\u0026ndash;291\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTang JD, Grady AJ, Nickel CJ, Ryan LE, Malone A, Canvasser L et al (2023) Systematic Review of Endolymphatic Sac Tumor Treatment and Outcomes. Otolaryngol neck Surg Off J Am Acad Otolaryngol Neck Surg 168(3):282\u0026ndash;290\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLyons TP, Barry L, Sataloff RT (2025) Endolymphatic Sac Tumor. Ear Nose Throat J 104(9):556\u0026ndash;558\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRodrigues S, Fagan P, Turner J (2004) Endolymphatic sac tumors: A review of the St. Vincent\u0026rsquo;s Hospital experience. Otol Neurotol 25(4):599\u0026ndash;603\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLe H, Zhang H, Tao W, Lin L, Li J, Ma L et al (2019) Clinicoradiologic characteristics of endolymphatic sac tumors. Eur Arch oto-rhino-laryngology Off J Eur Fed Oto-Rhino-Laryngological Soc Affil with Ger Soc Oto-Rhino-Laryngology -. Head Neck Surg 276(10):2705\u0026ndash;2714\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePoletti AM, Dubey SP, Colombo G, Cugini G, Mazzoni A (2016) Treatment of endolymphatic sac tumour (Papillary adenocarcinoma) of the temporal bone. Reports Pract Oncol Radiother [Internet]. ;21(4):391\u0026ndash;4. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://dx.doi.org/10.1016/j.rpor.2015.06.003\u003c/span\u003e\u003cspan address=\"10.1016/j.rpor.2015.06.003\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJoy HM, Barker CS, Millar JS, Davis A (2002) Radiological considerations in the diagnosis of an endolymphatic sac tumour. Clin Radiol 57(7):652\u0026ndash;654\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHeffner DK (1989) Low-grade adenocarcinoma of probable endolymphatic sac origin A clinicopathologic study of 20 cases. Cancer 64(11):2292\u0026ndash;2302\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePoletti AM, Dubey SP, Barb\u0026ograve; R, Pericotti S, Fiamengo B, Colombo G et al (2013) Sporadic endolymphatic sac tumor: its clinical, radiological, and histological features, management, and follow-up. Head Neck 35(7):1043\u0026ndash;1047\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNevoux J, Nowak C, Vellin J-F, Lepajolec C, Sterkers O, Richard S et al (2014) Management of endolymphatic sac tumors: sporadic cases and von Hippel-Lindau disease. Otol Neurotol Off Publ Am Otol Soc Am Neurotol Soc [and] Eur Acad Otol Neurotol 35(5):899\u0026ndash;904\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"the-egyptian-journal-of-otolaryngology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [The Egyptian Journal of Otolaryngology](https://ejo.springeropen.com/)","snPcode":"43163","submissionUrl":"https://submission.springernature.com/new-submission/43163/3","title":"The Egyptian Journal of Otolaryngology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Endolymphatic sac tumor, Temporal bone tumor, Facial nerve palsy, Hearing loss, Skull base surgery, Case report, Neurotology","lastPublishedDoi":"10.21203/rs.3.rs-8264102/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8264102/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground: Endolymphatic sac tumors (ELSTs) are uncommon low-grade tumors with highly local aggressive features. These tumors could be associated with Von Hippel-Lindau disease or isolated. These tumors mostly present with audiovestibular and neurological symptoms. The definitive diagnosis can be achieved through histopathological examination of the post-surgical excised specimen.\u003c/p\u003e\n\u003cp\u003eCase Presentation: We present a case of a female patient with a chief complaint of headache, unilateral hearing loss, and facial paralysis. Imaging studies demonstrated a mass in the left temporal bone. Intraoperatively, several hard, blood-stained fragments of bone and soft tissue. A complete microsurgical removal was achieved through a transmastoid-translabyrinthine approach with a preserved dura. Histopathological analysis confirmed the diagnosis of endolymphatic sac tumor. The patient was discharged with no new neurological deficit after the surgery with OPD follow up and referral for genetic studies.\u003c/p\u003e\n\u003cp\u003eConclusion: The reported case showed an unusual pre- and intraoperative presentation of endolymphatic sac tumor necessitating the need for early identification of such cases. Complete microsurgical removal remains the mainstay of treatment.\u003c/p\u003e","manuscriptTitle":"Unusual Endolymphatic Sac Tumor: Case Report and Literature Review","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-30 01:35:28","doi":"10.21203/rs.3.rs-8264102/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-04-17T08:45:45+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"17317611893623555249684997277610619102","date":"2026-03-30T08:12:16+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-04T02:40:32+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"163153914854010631667857901508385926304","date":"2026-01-28T02:01:11+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-27T21:43:36+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-04T08:38:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-04T08:38:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"The Egyptian Journal of Otolaryngology","date":"2025-12-02T20:51:24+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"the-egyptian-journal-of-otolaryngology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [The Egyptian Journal of Otolaryngology](https://ejo.springeropen.com/)","snPcode":"43163","submissionUrl":"https://submission.springernature.com/new-submission/43163/3","title":"The Egyptian Journal of Otolaryngology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Open","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0cb635f9-3846-42b6-ae8a-5d7dc6c46686","owner":[],"postedDate":"January 30th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-24T14:09:45+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-30 01:35:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8264102","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8264102","identity":"rs-8264102","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}