Rare Incidental Retroperitoneal Schwannoma Discovered as an Adrenal Mass Upon Pre- Renal Transplant Workup, Case Report

Rare Incidental Retroperitoneal Schwannoma Discovered as an Adrenal Mass Upon Pre- Renal Transplant Workup, Case Report | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Rare Incidental Retroperitoneal Schwannoma Discovered as an Adrenal Mass Upon Pre- Renal Transplant Workup, Case Report Abdulaziz Aldrees, Ahad Alotaibi, Mariam Alshammari, Sultan Alhabdan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5938235/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Schwannomas are benign tumors originating from the Schwann cells of the peripheral nervous system, that can occur in any part of the body, but are typically located in the head, neck, and flexor surface of extremities. Retroperitoneal schwannoma is sporadic and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas. In the majority of the patients the lesion was incidentally discovered upon investigation for another reason. Case presentation: We are reporting a 38-year-old female patient known to have uncontrolled type 2 diabetes mellitus and hypertension, which was complicated by end-stage renal disease, and started on hemodialysis in 2021. The patient was planned for a kidney transplant, and a pre-renal transplant workup was initiated. Abdomen CT was done as part of the workup, and it showed incidental findings of adrenal mass 4.3 x 3.1 cm. The patient underwent further images for characterization of this mass by MRI and PET-CT scan, and further investigation showed a non-functioning tumor. She was planned for laparoscopic adrenalectomy and was admitted electively for the surgery. Post-operative histopathology revealed Schwannoma. Conclusions Retroperitoneal schwannoma is very rare, and the diagnosis is challenging. Most often found to be incidental upon investigating for another purpose. The radiological images play an essential role in the diagnostic approach. Resection is the mainstay for management, and the histopathologic examination is the most reliable method to diagnose retroperitoneal schwannoma. Schwannoma adrenal Retroperitoneal Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Schwannomas (neurilemmoma) are encapsulated nerve sheath tumors that are usually located on the head, neck, and flexor surfaces of the extremities. Retroperitoneal schwannoma (RS) particularly is very rare and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas ( 1 ) . The diagnosis is challenging and most often found to be an incidental finding with late presentation ( 2 ) . Patients usually exhibit non-specific complaints like abdominal pain, discomfort, constipation or if reaches a significant size it may cause compressive symptoms ( 3 ) . Furthermore, some of them may present with deep venous thrombosis ( 2 ) . Radiology images play an essential role in the diagnostic approach ( 3 ) . Enhanced Computed Tomography (CT) scan classically will identify a well-defined tumor with slightly low density compared with soft tissue due to the high presence of myelin and fat ( 3 ) Magnetic Resonance Imaging (MRI) is superior to CT in defining the margins and identifying the nerve origin ( 3 ) . However, the diagnosis of schwannoma based on imaging or even with needle biopsy is difficult and has many limitations ( 4 )( 6 ) . Hence, complete surgical resection is recommended in almost all cases and provides an accurate pathological examination ( 4 ) . Differential diagnosis includes neurofibromas, paragangliomas, and ganglioneuromas. Neurofibromas will show round or irregularly shaped masses along the course of the nerves, which a well-defined but lacking capsules, occasional cysts, and hemorrhages, and heterogeneous enhancement on enhanced images ( 5 ) . Paraganglioma is mostly located in the sympathetic chain on both sides of the spine, and may be complemented by cystic degeneration, calcification or necrosis, as well as it may be accompanied by paroxysmal hypertension and the enhancement after enhanced study is more obvious than that of schwannoma ( 5 ) . The ganglioneuroma appears with a clear boundary, and the lesions may show pseudopodia-like or embedded growth, and usually the density is uniform, and accompanied by calcification or fatty degeneration, less cystic consolidation, and the enhancement study is not clear ( 5 ) . Needle Biopsy is generally not recommended due to the multiple pitfalls and increased risk of complications particularly when it is located adjacent to blood vessels, the risk of blood vessel damage is high ( 6 ) . Moreover, the heterogeneity of the tumor lesions makes the needle biopsy inaccurate or may lead to the misdiagnosis of malignant tumors ( 6 ) . Retrospective Study of 79 patients between 2010–2020 diagnosed based on pathological examination after surgical resection with RS and concluded that preoperative diagnosis of RS is usually not possible due to its rarity and lack of special clinical and radiographic features. RS should be considered in the differential diagnosis for unilateral well-circumscribed heterogeneous retroperitoneal masses with heterogeneous or delayed enhancement ( 7 ) . In this Report, we are presenting a case of incidental retroperitoneal schwannoma that was discovered as an adrenal mass upon pre-renal transplant workup. Case Report We are reporting a 38-year-old female patient known to have uncontrolled type 2 diabetes mellitus and hypertension, which was complicated by end-stage renal disease (ESRD), and started on hemodialysis in 2021 through left arteriovenous fistula. The patient was planned for a kidney transplant by the nephrology team, and a pre-renal transplant workup was initiated. Abdomen Computed Tomography (CT) was done as part of the workup, and it showed incidental findings of adrenal mass. The patient was referred to our clinic for further management. The patient was seen in the clinic, and she was asymptomatic, CT abdomen Images were reviewed as shown in (Fig. 1 ) which showed that the native kidneys demonstrate decreased enhancement related to medical renal disease. No renal masses. There is a 4.3 x 3.1 cm left para-aortic mass with punctate calcification and heterogenous enhancement, the mass is abutting the left adrenal, stomach, and posterior border of the pancreas, the region of the mass indeterminate. There are few prominent para-aortic and retroperitoneal lymph nodes the largest measures 0.7 cm in the left common iliac group. The liver demonstrates heterogenous enhancement likely related to the patient's underlying condition with no obvious focal mass. A left suprarenal heterogenous mass could be arising from the left adrenal gland, further evaluation by Magnetic Resonance Imaging (MRI) is advised. The case was flagged as an oncology-suspected case. MRI has been arranged for further evaluation and characterization of the mass as shown in (Fig. 2 ) a well-defined left para-aortic mass measuring 2.2 x 4.5 x 3.5 cm (transverse, anterior-posterior, craniocaudal). It is hypointense in T1 and heterogeneously hyperintense in T2 with progressive slow and delayed enhancement. It shows mild restriction diffusion and contains central calcification and necrosis. The mass mostly arises from the left adrenal gland and appears separable from the spleen, and pancreas with no invasion to the adjacent structures. The native kidneys show poor enhancement keeping with poor functioning kidneys. The impression was a 4.5 cm left adrenal mass demonstrating slow delayed enhancement with central calcification and necrosis. Differential diagnoses include ganglioneuroma and hemangioma. Given the size of the mass and the absence of previous imaging studies to compare with, further evaluation by biopsy or PET/CT is advised to confirm benignity and exclude the unlikely possibility of adrenocortical carcinoma. Positron emission tomography (PET)-CT scan done (Fig. 3 ), that showed diffuse intense FDG uptake throughout the stomach, associated with gastric wall thickening, maximum standardized uptake value (SUV max) 16.4. Mild heterogeneous FDG uptake in mixed density left adrenal mass with internal calcifications SUV max 3.3. radiological Impression was left adrenal mass with mildly FDG-avid, differential is wide and may include pheochromocytoma or previous adrenal hemorrhage. Intensely FDG-avid gastric wall thickening, worrisome for an infiltrative malignancy, such as MALT lymphoma for histopathological correlation. Esophagogastroduodenoscopy (EGD) was done, and it showed moderate to severe gastritis, raised erosion with hematin stain, proximal gastric cardia raised lesion near to gastroesophageal junction (GEJ), and feature of duodenitis. Multiple biopsies taken from the proximal gastric lesion that were consistent with hyperplastic polyp with H. pylori infection, and foci of intestinal metaplasia are noted. The patient then was seen by the medical endocrine team as the final step before the surgical intervention. A functioning workup was ordered and was negative for Metanephrine, and normetanephrine, furthermore, 1 mg dexamethasone suppression test was done but was not suppressed completely, which could be secondary to ESRD status as per the endocrinology impression. The patient clinically had no evidence of Cushing or pheochromocytoma or any other adrenal-secreting tumors like (conns syndrome) and was cleared for surgery. She was planned for laparoscopic adrenalectomy and was admitted electively for the surgery. Intra-operatively the left adrenal gland was identified, and it looked normal, large para-aortic mass was identified close to the adrenal measuring about 5 to 6 cm, adherent and stuck to the adrenal mass into the back of the muscle and to the splenic artery, however, it was resected off and excised completely. There were veins draining to the renal vein and were clipped. The final procedure was retroperitoneal mass resection without adrenalectomy as shown in (Fig. 4 ). Patient tolerated the surgery and had an uncomplicated and smooth postoperative course. The patient was discharged on the second day postoperatively in good health and seen in the clinic after 2 weeks with no complaints and healed wounds. In the histopathology lab, the specimen was received in formalin in one container, grossly weighing 22.6 grams and measuring 4.5 x 3.0 x 2.0 cm. The outer surface is smooth and inked black. Serial sectioning reveals a tan-yellow calcified cut surface involving the entire specimen. No intact adrenal gland is found. Representative sections are submitted in five cassettes. Under microscopic examination and panel of immunostains were performed. Tumor cells are positive for S100, while negative for NFP, SMA, HMB45, MelanA, and Desmin. Discussion Schwannomas are benign tumors that originate from the Schwann cells of the peripheral nervous system, that can occur in any part of the body, but are typically located in the head, neck, and flexor surface of extremities ( 8 ) . Retroperitoneal schwannomas are uncommon, with a rate of less than 5% of all schwannomas, and rarely found in the adrenal glands ( 8 ) . Similar reported cases of retroperitoneal schwannomas, as well as literature review by Wilson et al. who documented 121 cases from (1986 till 2018) ( 9 ) . Retroperitoneal schwannomas are rarely identified, and this has been proven by Li et al. who identified only 19 adrenal schwannomas in a series of almost 4,000 adrenal lesions ( 9 )( 10 ) . In the majority of the reported cases, the patients were asymptomatic, as our patient, and the lesion was incidentally discovered upon investigation for another reason ( 9 )( 10 ) . The rarity of these cases makes the pre-operative diagnosis difficult to establish, but benign schwannoma is a differential consideration for any suspected suprarenal malignant lesions ( 9 )( 10 ) . A few radiological features by CT scan can help in the differential diagnosis as documented in the literature, and was presented in our case as well, these features include well-encapsulated margins, punctate calcifications, marked heterogeneity with a centrally cystic/necrotic core which was presented in 50% of the reported cases ( 9 ) . Moreover, the diameter of all of the tumors was noticed to be greater than 4 cm, and the calcifications and clear boundaries can be seen in almost all lesions by CT scan ( 10 ) . Case Series by Kostek et al. reported further characterization of adrenal Schwannomas based on MRI and PET-CT scan findings. In MRI studies, intensity characteristics of adrenal schwannomas may be low in T1-weighted images and high in T2-weighted images. However, these lesions may have heterogeneous findings as in CT scans. Adrenal schwannomas may show increased FDG uptake, which may increase suspicion of malignancy ( 12 ) . Indeed, histopathologic examination is the most reliable method to diagnose adrenal schwannoma ( 10 )( 11 )( 12 ) . Surgical resection is the mainstay for management of adrenal schwannomas ( 13 )( 14 ) . Laparoscopic adrenalectomy is considered the gold standard procedure for the treatment of benign small- to medium-sized adrenal masses (< 6 cm), and many advantages such as low morbidity rate, short hospitalization, and rapid patient recovery ( 13 ) . However, there are no differences in outcomes in laparoscopic or open techniques ( 14 ) . Generally, patients with post-operatively pathology of Schwannomas had good outcomes and prognosis with low incidence of recurrence ( 15 ) . Conclusion Retroperitoneal schwannoma particularly is very rare and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas. The diagnosis is challenging and most often found to be incidental upon investigation for another reason. Radiology images play an essential role in the diagnostic approach, but the rarity of these cases makes the pre-operative diagnosis difficult to establish. Surgical resection is the mainstay for management, and the histopathologic examination is the most reliable method to diagnose adrenal schwannoma. Declarations Consent for publication The patient gave written informed consent to publish this case report and any accompanying images. The editor-in-chief of this journal can review a copy of the written consent. The report has been carried out following the Guideline. Ethics approval and consent to participate: The Institutional Review Board, King Abdullah International Medical Research Center, waived the need for ethical approval. written informed consent was obtained. Funding: There was no financial support. Author Contribution All Authors mentioned Abdulaziz Aldrees, Ahad Alotaibi, Mariam Alshammari, and Sultan Alhabdan contributed equally in writing and reviewing the article Acknowledgments: Not applicable Availability of data and materials: Not applicable; no raw data to report. The consent was attached as a supplemental file Competing interests : The authors declare that they have no competing interests Clinical trial number : not applicable References Debaibi M, Essid R, Sghair A, Zouari R, Sahnoun M, Dhaoui A, et al. Retroperitoneal Schwannoma: Uncommon location of a benign tumor. Clinical Case Reports. 2022 Apr;10(4). doi:10.1002/ccr3.5726 Lamris mohamed A, El Yamine O, El Jay SR, hajri A, boufettal R, erreguibi D, et al. Retroperitoneal Shwannoma: A case report. Annals of Medicine and Surgery. 2021 Oct;70:102785. doi:10.1016/j.amsu.2021.102785 Harhar M, Ramdani A, Bouhout T, Serji B, El Harroudi T. Retroperitoneal Schwannoma: Two rare case reports. Cureus. 2021 Feb 20; doi:10.7759/cureus.13456 Ogose A, Kawashima H, Hatano H, Ariizumi T, Sasaki T, Yamagishi T, et al. The natural history of incidental retroperitoneal schwannomas. PLOS ONE. 2019 Apr 15;14(4). doi:10.1371/journal.pone.0215336 tang maosheng, liu wenqing, chen xiaobing, zou boyuan, liu shibo, xiao mengmeng, et al. Analysis of benign retroperitoneal schwannomas: A single-center experience. Journal of Neurological Surgery Part A: Central European Neurosurgery. 2022 Sept 13; doi:10.1055/a-1942-2310 Wu Q, Liu B, Lu J, Chang H. Clinical characteristics and treatment strategy of retroperitoneal schwannoma adjacent to important abdominal vessels: Three case reports and literature review. Frontiers in Surgery. 2021 Jan 14;7. doi:10.3389/fsurg.2020.605867 Xiao J, Cai L, Pu J, Liu W, Jia C, He X. Clinical characteristics and prognosis of cystic degeneration in retroperitoneal schwannoma: A retrospective study of 79 patients. Cancer Medicine. 2022 Nov 28;12(5):5615–29. doi:10.1002/cam4.5411 Dogra P, Sundin A, Juhlin CC, Calissendorff J, Falhammar H, Bancos I. Rare benign adrenal lesions. European Journal of Endocrinology. 2023 Mar 21;188(4):407–20. doi:10.1093/ejendo/lvad036 1. Wilson MP, Katlariwala P, Huang J, Low G, Wiebe E. Benign adrenal and suprarenal retroperitoneal schwannomas can mimic aggressive adrenal malignancies: Case report and review of the literature. Intractable & Rare Diseases Research. 2020 Aug 31;9(3):156–62. doi:10.5582/irdr.2020.01027 Li S-Q, Zhang Y-S, Shi J, Li H-Z. Clinical features and retroperitoneal laparoscopic resection of adrenal schwannoma in 19 patients. Endocrine Practice. 2015 Apr;21(4):323–9. doi:10.4158/ep14453.or Incampo G, Di Filippo L, Grossrubatscher EM, Dalino Ciaramella P, Frara S, Giustina A, et al. Adrenal schwannoma: Why should endocrinologists be aware of this uncommon tumour? Endocrine. 2022 Feb 12;75(3):684–97. doi:10.1007/s12020-022-02997-x Kostek M, Unlu MT, Caliskan O, Aygun N, Iscan Y, Dural AC, et al. An unusual finding after adrenal surgery: A case series of Adrenal schwannomas. Frontiers in Surgery. 2023 May 24;10. doi:10.3389/fsurg.2023.1175633 Huang H, Ding Q, Lin X, Li D, Zeng J, Fu W. Clinical features and outcomes of adrenal schwannoma: A study of 13 cases from a single centre. Endocrine Connections. 2021 May 1;10(5):543–9. doi:10.1530/ec-21-0062 Timilsina S, Joshi SP, Sharma S, Kharel S, Karki S, Tiwari SB, et al. Adrenal schwannoma: A case report of an unusual incidentaloma. International Journal of Surgery Case Reports. 2021 Jun;83:106018. doi:10.1016/j.ijscr.2021.106018 Montebello A, Psaila A, Fava S. Para-adrenal schwannoma mimicking a giant adrenal lesion. BMJ Case Reports. 2021 Jul;14(7). doi:10.1136/bcr-2021-243652 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-5938235","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":440621498,"identity":"935d82b2-9d16-4a9d-818a-ff61561ec0d5","order_by":0,"name":"Abdulaziz Aldrees","email":"","orcid":"","institution":"King Abdulaziz Medical City, Ministry of National Guard Health Affairs","correspondingAuthor":false,"prefix":"","firstName":"Abdulaziz","middleName":"","lastName":"Aldrees","suffix":""},{"id":440621499,"identity":"3ce12c24-130d-46b0-8692-df371c1451e9","order_by":1,"name":"Ahad 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x 3.1 cm left para-aortic mass, and enlarged lymph node 0.7 cm in the left common iliac\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5938235/v1/ca97dc0e2f990de6ce5d427a.jpg"},{"id":80295834,"identity":"616bb18c-9064-4a2d-8072-4854a6b97101","added_by":"auto","created_at":"2025-04-10 08:36:41","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":45616,"visible":true,"origin":"","legend":"\u003cp\u003eAbdomen MRI: showed 4.5 cm left adrenal mass that demonstrates slow delayed enhancement with central calcification and necrosis.\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5938235/v1/2856a8f2660c1038098cbf2c.jpg"},{"id":80295836,"identity":"8ba7bfd7-fe61-4eb5-a6b1-cfc3be52d06e","added_by":"auto","created_at":"2025-04-10 08:36:41","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":17604,"visible":true,"origin":"","legend":"\u003cp\u003ePET/CT Oncology\u003c/p\u003e\n\u003cp\u003eMild heterogeneous FDG uptake in mixed-densityleft adrenal mass with internal calcifications\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5938235/v1/2c8b89a4045416ceb71072f1.jpg"},{"id":80295837,"identity":"1996af05-b06a-4e2d-bf14-93e71f20f205","added_by":"auto","created_at":"2025-04-10 08:36:41","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":64875,"visible":true,"origin":"","legend":"\u003cp\u003eIntra-operative findings, yellow arrow showed the mass.\u003c/p\u003e\n\u003cp\u003eArrow A showed left kidney\u003c/p\u003e\n\u003cp\u003eArrow B showed left adrenal\u003c/p\u003e\n\u003cp\u003eArrow C showed spleen\u003c/p\u003e\n\u003cp\u003eArrow D showed splenic vessels\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5938235/v1/e9c665b7e7683cf2486f8d1b.jpg"},{"id":88591243,"identity":"29e25270-dda4-4ed0-9550-5bdcf12d8315","added_by":"auto","created_at":"2025-08-08 05:40:04","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":580852,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5938235/v1/95c1a2ee-9810-432c-a3da-0d91dceeb289.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Rare Incidental Retroperitoneal Schwannoma Discovered as an Adrenal Mass Upon Pre- Renal Transplant Workup, Case Report","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSchwannomas (neurilemmoma) are encapsulated nerve sheath tumors that are usually located on the head, neck, and flexor surfaces of the extremities. Retroperitoneal schwannoma (RS) particularly is very rare and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas \u003csup\u003e(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)\u003c/sup\u003e. The diagnosis is challenging and most often found to be an incidental finding with late presentation \u003csup\u003e(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/sup\u003e. Patients usually exhibit non-specific complaints like abdominal pain, discomfort, constipation or if reaches a significant size it may cause compressive symptoms \u003csup\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e. Furthermore, some of them may present with deep venous thrombosis\u003csup\u003e(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e)\u003c/sup\u003e. Radiology images play an essential role in the diagnostic approach\u003csup\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e. Enhanced Computed Tomography (CT) scan classically will identify a well-defined tumor with slightly low density compared with soft tissue due to the high presence of myelin and fat \u003csup\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e Magnetic Resonance Imaging (MRI) is superior to CT in defining the margins and identifying the nerve origin\u003csup\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e)\u003c/sup\u003e. However, the diagnosis of schwannoma based on imaging or even with needle biopsy is difficult and has many limitations \u003csup\u003e(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/sup\u003e. Hence, complete surgical resection is recommended in almost all cases and provides an accurate pathological examination\u003csup\u003e(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)\u003c/sup\u003e. Differential diagnosis includes neurofibromas, paragangliomas, and ganglioneuromas. Neurofibromas will show round or irregularly shaped masses along the course of the nerves, which a well-defined but lacking capsules, occasional cysts, and hemorrhages, and heterogeneous enhancement on enhanced images \u003csup\u003e(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/sup\u003e. Paraganglioma is mostly located in the sympathetic chain on both sides of the spine, and may be complemented by cystic degeneration, calcification or necrosis, as well as it may be accompanied by paroxysmal hypertension and the enhancement after enhanced study is more obvious than that of schwannoma \u003csup\u003e(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/sup\u003e. The ganglioneuroma appears with a clear boundary, and the lesions may show pseudopodia-like or embedded growth, and usually the density is uniform, and accompanied by calcification or fatty degeneration, less cystic consolidation, and the enhancement study is not clear \u003csup\u003e(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e)\u003c/sup\u003e. Needle Biopsy is generally not recommended due to the multiple pitfalls and increased risk of complications particularly when it is located adjacent to blood vessels, the risk of blood vessel damage is high \u003csup\u003e(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/sup\u003e. Moreover, the heterogeneity of the tumor lesions makes the needle biopsy inaccurate or may lead to the misdiagnosis of malignant tumors \u003csup\u003e(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)\u003c/sup\u003e. Retrospective Study of 79 patients between 2010\u0026ndash;2020 diagnosed based on pathological examination after surgical resection with RS and concluded that preoperative diagnosis of RS is usually not possible due to its rarity and lack of special clinical and radiographic features. RS should be considered in the differential diagnosis for unilateral well-circumscribed heterogeneous retroperitoneal masses with heterogeneous or delayed enhancement \u003csup\u003e(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e)\u003c/sup\u003e. In this Report, we are presenting a case of incidental retroperitoneal schwannoma that was discovered as an adrenal mass upon pre-renal transplant workup.\u003c/p\u003e"},{"header":"Case Report","content":"\u003cp\u003eWe are reporting a 38-year-old female patient known to have uncontrolled type 2 diabetes mellitus and hypertension, which was complicated by end-stage renal disease (ESRD), and started on hemodialysis in 2021 through left arteriovenous fistula. The patient was planned for a kidney transplant by the nephrology team, and a pre-renal transplant workup was initiated. Abdomen Computed Tomography (CT) was done as part of the workup, and it showed incidental findings of adrenal mass. The patient was referred to our clinic for further management. The patient was seen in the clinic, and she was asymptomatic, CT abdomen Images were reviewed as shown in (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) which showed that the native kidneys demonstrate decreased enhancement related to medical renal disease. No renal masses. There is a 4.3 x 3.1 cm left para-aortic mass with punctate calcification and heterogenous enhancement, the mass is abutting the left adrenal, stomach, and posterior border of the pancreas, the region of the mass indeterminate. There are few prominent para-aortic and retroperitoneal lymph nodes the largest measures 0.7 cm in the left common iliac group. The liver demonstrates heterogenous enhancement likely related to the patient's underlying condition with no obvious focal mass. A left suprarenal heterogenous mass could be arising from the left adrenal gland, further evaluation by Magnetic Resonance Imaging (MRI) is advised. The case was flagged as an oncology-suspected case.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eMRI has been arranged for further evaluation and characterization of the mass as shown in (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) a well-defined left para-aortic mass measuring 2.2 x 4.5 x 3.5 cm (transverse, anterior-posterior, craniocaudal). It is hypointense in T1 and heterogeneously hyperintense in T2 with progressive slow and delayed enhancement. It shows mild restriction diffusion and contains central calcification and necrosis. The mass mostly arises from the left adrenal gland and appears separable from the spleen, and pancreas with no invasion to the adjacent structures. The native kidneys show poor enhancement keeping with poor functioning kidneys. The impression was a 4.5 cm left adrenal mass demonstrating slow delayed enhancement with central calcification and necrosis. Differential diagnoses include ganglioneuroma and hemangioma. Given the size of the mass and the absence of previous imaging studies to compare with, further evaluation by biopsy or PET/CT is advised to confirm benignity and exclude the unlikely possibility of adrenocortical carcinoma.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePositron emission tomography (PET)-CT scan done (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), that showed diffuse intense FDG uptake throughout the stomach, associated with gastric wall thickening, maximum standardized uptake value (SUV max) 16.4. Mild heterogeneous FDG uptake in mixed density left adrenal mass with internal calcifications SUV max 3.3. radiological Impression was left adrenal mass with mildly FDG-avid, differential is wide and may include pheochromocytoma or previous adrenal hemorrhage. Intensely FDG-avid gastric wall thickening, worrisome for an infiltrative malignancy, such as MALT lymphoma for histopathological correlation.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eEsophagogastroduodenoscopy (EGD) was done, and it showed moderate to severe gastritis, raised erosion with hematin stain, proximal gastric cardia raised lesion near to gastroesophageal junction (GEJ), and feature of duodenitis. Multiple biopsies taken from the proximal gastric lesion that were consistent with hyperplastic polyp with H. pylori infection, and foci of intestinal metaplasia are noted.\u003c/p\u003e \u003cp\u003eThe patient then was seen by the medical endocrine team as the final step before the surgical intervention. A functioning workup was ordered and was negative for Metanephrine, and normetanephrine, furthermore, 1 mg dexamethasone suppression test was done but was not suppressed completely, which could be secondary to ESRD status as per the endocrinology impression. The patient clinically had no evidence of Cushing or pheochromocytoma or any other adrenal-secreting tumors like (conns syndrome) and was cleared for surgery.\u003c/p\u003e \u003cp\u003eShe was planned for laparoscopic adrenalectomy and was admitted electively for the surgery. Intra-operatively the left adrenal gland was identified, and it looked normal, large para-aortic mass was identified close to the adrenal measuring about 5 to 6 cm, adherent and stuck to the adrenal mass into the back of the muscle and to the splenic artery, however, it was resected off and excised completely. There were veins draining to the renal vein and were clipped. The final procedure was retroperitoneal mass resection without adrenalectomy as shown in (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Patient tolerated the surgery and had an uncomplicated and smooth postoperative course. The patient was discharged on the second day postoperatively in good health and seen in the clinic after 2 weeks with no complaints and healed wounds.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the histopathology lab, the specimen was received in formalin in one container, grossly weighing 22.6 grams and measuring 4.5 x 3.0 x 2.0 cm. The outer surface is smooth and inked black. Serial sectioning reveals a tan-yellow calcified cut surface involving the entire specimen. No intact adrenal gland is found. Representative sections are submitted in five cassettes. Under microscopic examination and panel of immunostains were performed. Tumor cells are positive for S100, while negative for NFP, SMA, HMB45, MelanA, and Desmin.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSchwannomas are benign tumors that originate from the Schwann cells of the peripheral nervous system, that can occur in any part of the body, but are typically located in the head, neck, and flexor surface of extremities \u003csup\u003e(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/sup\u003e. Retroperitoneal schwannomas are uncommon, with a rate of less than 5% of all schwannomas, and rarely found in the adrenal glands \u003csup\u003e(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e)\u003c/sup\u003e. Similar reported cases of retroperitoneal schwannomas, as well as literature review by Wilson et al. who documented 121 cases from (1986 till 2018) \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/sup\u003e. Retroperitoneal schwannomas are rarely identified, and this has been proven by Li et al. who identified only 19 adrenal schwannomas in a series of almost 4,000 adrenal lesions \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e. In the majority of the reported cases, the patients were asymptomatic, as our patient, and the lesion was incidentally discovered upon investigation for another reason \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e. The rarity of these cases makes the pre-operative diagnosis difficult to establish, but benign schwannoma is a differential consideration for any suspected suprarenal malignant lesions \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e. A few radiological features by CT scan can help in the differential diagnosis as documented in the literature, and was presented in our case as well, these features include well-encapsulated margins, punctate calcifications, marked heterogeneity with a centrally cystic/necrotic core which was presented in 50% of the reported cases \u003csup\u003e(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e)\u003c/sup\u003e. Moreover, the diameter of all of the tumors was noticed to be greater than 4 cm, and the calcifications and clear boundaries can be seen in almost all lesions by CT scan \u003csup\u003e(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)\u003c/sup\u003e. Case Series by Kostek et al. reported further characterization of adrenal Schwannomas based on MRI and PET-CT scan findings. In MRI studies, intensity characteristics of adrenal schwannomas may be low in T1-weighted images and high in T2-weighted images. However, these lesions may have heterogeneous findings as in CT scans. Adrenal schwannomas may show increased FDG uptake, which may increase suspicion of malignancy\u003csup\u003e(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/sup\u003e. Indeed, histopathologic examination is the most reliable method to diagnose adrenal schwannoma \u003csup\u003e(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e)(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e)(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e)\u003c/sup\u003e. Surgical resection is the mainstay for management of adrenal schwannomas \u003csup\u003e(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/sup\u003e. Laparoscopic adrenalectomy is considered the gold standard procedure for the treatment of benign small- to medium-sized adrenal masses (\u0026lt;\u0026thinsp;6 cm), and many advantages such as low morbidity rate, short hospitalization, and rapid patient recovery \u003csup\u003e(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e)\u003c/sup\u003e. However, there are no differences in outcomes in laparoscopic or open techniques \u003csup\u003e(\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e)\u003c/sup\u003e. Generally, patients with post-operatively pathology of Schwannomas had good outcomes and prognosis with low incidence of recurrence\u003csup\u003e(\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e)\u003c/sup\u003e.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eRetroperitoneal schwannoma particularly is very rare and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas. The diagnosis is challenging and most often found to be incidental upon investigation for another reason. Radiology images play an essential role in the diagnostic approach, but the rarity of these cases makes the pre-operative diagnosis difficult to establish. Surgical resection is the mainstay for management, and the histopathologic examination is the most reliable method to diagnose adrenal schwannoma.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eConsent for publication\u003c/strong\u003e \u003cp\u003e The patient gave written informed consent to publish this case report and any accompanying images. The editor-in-chief of this journal can review a copy of the written consent. The report has been carried out following the Guideline.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003e \u003cp\u003eThe Institutional Review Board, King Abdullah International Medical Research Center, waived the need for ethical approval. written informed consent was obtained.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThere was no financial support.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAll Authors mentioned Abdulaziz Aldrees, Ahad Alotaibi, Mariam Alshammari, and Sultan Alhabdan contributed equally in writing and reviewing the article\u003c/p\u003e\u003ch2\u003eAcknowledgments:\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e\u003ch2\u003eAvailability of data and materials:\u003c/h2\u003e \u003cp\u003eNot applicable; no raw data to report. The consent was attached as a supplemental file\u003c/p\u003e \u003cp\u003e \u003cb\u003eCompeting interests\u003c/b\u003e: The authors declare that they have no competing interests\u003c/p\u003e \u003cp\u003e \u003cb\u003eClinical trial number\u003c/b\u003e: not applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eDebaibi M, Essid R, Sghair A, Zouari R, Sahnoun M, Dhaoui A, et al. Retroperitoneal Schwannoma: Uncommon location of a benign tumor. Clinical Case Reports. 2022 Apr;10(4). doi:10.1002/ccr3.5726\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eLamris mohamed A, El Yamine O, El Jay SR, hajri A, boufettal R, erreguibi D, et al. Retroperitoneal Shwannoma: A case report. Annals of Medicine and Surgery. 2021 Oct;70:102785. doi:10.1016/j.amsu.2021.102785\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u0026nbsp;Harhar M, Ramdani A, Bouhout T, Serji B, El Harroudi T. Retroperitoneal Schwannoma: Two rare case reports. Cureus. 2021 Feb 20; doi:10.7759/cureus.13456\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eOgose A, Kawashima H, Hatano H, Ariizumi T, Sasaki T, Yamagishi T, et al. The natural history of incidental retroperitoneal schwannomas. PLOS ONE. 2019 Apr 15;14(4). doi:10.1371/journal.pone.0215336\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u0026nbsp;tang maosheng, liu wenqing, chen xiaobing, zou boyuan, liu shibo, xiao mengmeng, et al. Analysis of benign retroperitoneal schwannomas: A single-center experience. Journal of Neurological Surgery Part A: Central European Neurosurgery. 2022 Sept 13; doi:10.1055/a-1942-2310\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eWu Q, Liu B, Lu J, Chang H. Clinical characteristics and treatment strategy of retroperitoneal schwannoma adjacent to important abdominal vessels: Three case reports and literature review. Frontiers in Surgery. 2021 Jan 14;7. doi:10.3389/fsurg.2020.605867\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eXiao J, Cai L, Pu J, Liu W, Jia C, He X. Clinical characteristics and prognosis of cystic degeneration in retroperitoneal schwannoma: A retrospective study of 79 patients. Cancer Medicine. 2022 Nov 28;12(5):5615\u0026ndash;29. doi:10.1002/cam4.5411\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eDogra P, Sundin A, Juhlin CC, Calissendorff J, Falhammar H, Bancos I. Rare benign adrenal lesions. European Journal of Endocrinology. 2023 Mar 21;188(4):407\u0026ndash;20. doi:10.1093/ejendo/lvad036\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e1. Wilson MP, Katlariwala P, Huang J, Low G, Wiebe E. Benign adrenal and suprarenal retroperitoneal schwannomas can mimic aggressive adrenal malignancies: Case report and review of the literature. Intractable \u0026amp;amp; Rare Diseases Research. 2020 Aug 31;9(3):156\u0026ndash;62. doi:10.5582/irdr.2020.01027\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eLi S-Q, Zhang Y-S, Shi J, Li H-Z. Clinical features and retroperitoneal laparoscopic resection of adrenal schwannoma in 19 patients. Endocrine Practice. 2015 Apr;21(4):323\u0026ndash;9. doi:10.4158/ep14453.or\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u0026nbsp;Incampo G, Di Filippo L, Grossrubatscher EM, Dalino Ciaramella P, Frara S, Giustina A, et al. Adrenal schwannoma: Why should endocrinologists be aware of this uncommon tumour? Endocrine. 2022 Feb 12;75(3):684\u0026ndash;97. doi:10.1007/s12020-022-02997-x\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eKostek M, Unlu MT, Caliskan O, Aygun N, Iscan Y, Dural AC, et al. An unusual finding after adrenal surgery: A case series of Adrenal schwannomas. Frontiers in Surgery. 2023 May 24;10. doi:10.3389/fsurg.2023.1175633\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eHuang H, Ding Q, Lin X, Li D, Zeng J, Fu W. Clinical features and outcomes of adrenal schwannoma: A study of 13 cases from a single centre. Endocrine Connections. 2021 May 1;10(5):543\u0026ndash;9. doi:10.1530/ec-21-0062\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eTimilsina S, Joshi SP, Sharma S, Kharel S, Karki S, Tiwari SB, et al. Adrenal schwannoma: A case report of an unusual incidentaloma. International Journal of Surgery Case Reports. 2021 Jun;83:106018. doi:10.1016/j.ijscr.2021.106018\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eMontebello A, Psaila A, Fava S. Para-adrenal schwannoma mimicking a giant adrenal lesion. BMJ Case Reports. 2021 Jul;14(7). doi:10.1136/bcr-2021-243652 \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Schwannoma, adrenal, Retroperitoneal","lastPublishedDoi":"10.21203/rs.3.rs-5938235/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5938235/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eSchwannomas are benign tumors originating from the Schwann cells of the peripheral nervous system, that can occur in any part of the body, but are typically located in the head, neck, and flexor surface of extremities. Retroperitoneal schwannoma is sporadic and accounts for only 4% of all retroperitoneal tumors and 3% of all schwannomas. In the majority of the patients the lesion was incidentally discovered upon investigation for another reason.\u003c/p\u003e\u003ch2\u003eCase presentation:\u003c/h2\u003e \u003cp\u003eWe are reporting a 38-year-old female patient known to have uncontrolled type 2 diabetes mellitus and hypertension, which was complicated by end-stage renal disease, and started on hemodialysis in 2021. The patient was planned for a kidney transplant, and a pre-renal transplant workup was initiated. Abdomen CT was done as part of the workup, and it showed incidental findings of adrenal mass 4.3 x 3.1 cm. The patient underwent further images for characterization of this mass by MRI and PET-CT scan, and further investigation showed a non-functioning tumor. She was planned for laparoscopic adrenalectomy and was admitted electively for the surgery. Post-operative histopathology revealed Schwannoma.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e \u003cp\u003eRetroperitoneal schwannoma is very rare, and the diagnosis is challenging. Most often found to be incidental upon investigating for another purpose. The radiological images play an essential role in the diagnostic approach. Resection is the mainstay for management, and the histopathologic examination is the most reliable method to diagnose retroperitoneal schwannoma.\u003c/p\u003e","manuscriptTitle":"Rare Incidental Retroperitoneal Schwannoma Discovered as an Adrenal Mass Upon Pre- Renal Transplant Workup, Case Report","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-10 08:36:36","doi":"10.21203/rs.3.rs-5938235/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d3e4c4f8-be21-4aef-8250-b0680b72c3b9","owner":[],"postedDate":"April 10th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-08-08T05:31:40+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-10 08:36:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5938235","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5938235","identity":"rs-5938235","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}