Primary umbilical endometriosis in a 35-year-old Ethiopian woman: A case report

Umbilical endometriosis is a rare extra-pelvic presentation of endometriosis and comprises less than 1% of cases. Its recognition is especially difficult in resource-limited settings, where access to advanced imaging and specialist care is limited. Case presentation: A 35-year-old Ethiopian woman, para 2, presented with a complaint of a 2-year history of a progressively enlarging, painful umbilical mass. The pain was cyclical and coincided with menstruation. Physical examination showed a 4 cm by 5 cm black, firm, non-tender mass over the umbilicus. Ultrasound showed a heterogeneous non-encapsulated mass without intra-abdominal extension, and cytology of fine needle aspiration suggested endometrial type cells and stroma. Surgical excision under general anesthesia was done with 2 cm free circumferential margins, and histopathology was consistent with ectopic endometrial glands and stroma. Recovery was uneventful, and at the 9-month follow-up, there was complete healing with no recurrence. The patient was pain-free and had a good cosmetic result.

This case illustrates the importance of umbilical endometriosis in the differential diagnosis of a woman with cyclical abdominal wall pain. In resource-limited settings, clinical suspicion with basic modalities of imaging and histopathology can allow timely diagnosis and curative surgical management.

Umbilical endometriosis; Primary umbilical endometriosis; Villar’s nodule; Abdominal wall endometriosis; Ethiopia; Case report. Endometriosis is thought to affect an estimated 10% of women of reproductive age across the world. Extrapelvic local izations are uncommon; umbilical endometriosis (Villar’s nod ule) only occurs in 0.5-1% of all endometriosis found [8,9]. It usually manifests as cyclical pain, swelling, and/or discoloration of the umbilicus in synchrony with menses but is often mistaken for an umbilical hernia, pyogenic granuloma, or metastatic dis ease (Sister Mary Joseph’s nodule) [4,5,18]. Primary form of endometriosis develops without prior ab dominal surgery; secondary is after surgical seeding (after a cesarean section or laparoscopy) [1,2]. Reports from sub-Sa haran Africa are still rare, and diagnostic delay may addition ally be complicated by lack of access to imaging and pathology [1,3,4,6,7]. We present a case of primary umbilical endometrio sis in Ethiopia, covering a diagnostic pathway (ultrasound, CT and histopathology), surgical excision, and structured follow-up that employed available technical resources. Novelty statement The present case is one of the rare reports on primary um bilical endometriosis from Ethiopia and combines the use of cross-sectional imaging to define musculofascial invasion and describes an en bloc excision followed by a structured nine month follow-up without recurrence in a resource-poor setting. Patient information and history A 35-year-old Ethiopian woman, para 2, came with a pain ful umbilical mass for 2 years. The mass was small at first and grew gradually bigger. The pain was cyclic and coincided with menstruation. She denied dysmenorrhea, dyspareunia, heavy menstrual bleeding, pelvic pain, constipation, and abdominal distention. Menstrual cycles were regular (28-30 days), and menarche occurred at 13 years of age. Both deliveries were by spontaneous vaginal birth. She did not have any previous ab dominal surgery and had no relevant systemic illness. Clinical findings The patient was clinically stable with normal vital signs. Abdominal examination revealed a bluish, discrete, firm mass measuring 4×5 cm attached to the umbilical ring without over lying ulceration or scarring or dilated vessels overlying the ab dominal wall—it was mildly tender upon palpation (Figure 1). There was no palpable hernia and regional lymphadenopathy. The pelvic examination was normal (Table 1). Diagnostic assessment Laboratory studies were unremarkable (WBC 8.3×103/dL; hemoglobin 14 g/dL; platelets 251×103/dL). High-frequency abdominal ultrasound showed a 4 cm by 5 cm heterogeneous, non-capsulated lesion over the umbilical ring with low inter nal vascularity and no intra-abdominal extension. Fine needle aspiration cytology revealed endometrial-type cells, which in creased the suspicion of endometriosis before operation [16]. Cross-sectional imaging by CT showed a 4 cm by 5 cm het erogeneous soft tissue mass in the anterior abdominal wall in the umbilicus region, extending into the linea alba and rectus sheath, representing umbilical endometriosis with local inva sion of musculofascial parts (Figure 2). These data were supportive of primary umbilical endometriosis, confirmed later by histopathology (Table 1). | Time point | Event | |---|---| | 24 months before | Symptom onset: painful umbilical mass | | 1 month before | Ultrasound: heterogeneous mass over umbilical ring | | 1 month before | FNAC: endometrial-type cells | | 1 month before | CT scan: mass invading linea alba and rectus sheath | | Day 0 | En bloc excision with 2 cm margin; umbilicoplasty | | Post-op Day 3 | Discharge in stable condition | | Day 10 | First follow-up: wound healing satisfactory | | 1 month | Second follow-up: pain resolved | | 3 months | Third follow-up: no recurrence | | 6 months | Fourth follow-up: scar intact | | 9 months | Final follow-up: recurrence-free, good cosmetic outcome | Therapeutic intervention Under general anesthesia using endotracheal intubation, the abdomen was prepared and draped. Intraoperative findings showed a bluish mass that was approximately 4 cm by 5 cm and involved the umbilicus and extended to the linea alba and rec tus sheath (Figure 1). An elliptical circumferential incision was made with a 2 cm margin of normal tissue, which is in accor dance with recommendations for a wide local excision to mini mize recurrence. Dissection revealed extension to the posterior rectus sheath and parietal peritoneum just superior to the um bilicus with no intra-abdominal involvement—a feature associ ated with a favorable prognosis. Approximately 6 cm by 7cm of t issue was excised en bloc with the mass (Figure 2). A subcuta neous Penrose drain was inserted, and the abdominal wall was closed in layers. The postoperative course was uneventful, and the patient was discharged on the third postoperative day. Histopathology revealed multiple variable-sized endometri al glands with columnar epithelium and compact endometrial stroma in the inner dermis. Cystically dilated areas with hem orrhagic material, dilated blood vessels, and sheets of hemo siderin-rich macrophages were also observed, consistent with endometriosis (Figure 3A and 3B). Follow-up and outcomes Complete wound healing, resolution of pain, and a return to normal daily activities, and no clinical recurrence were ob served at 10 days, 1 month, 3 months, 6 months, and 9 months of follow-up visits. Scar integrity was satisfactory (Figure 4). No adjuvant hormonal therapy was done. Umbilical endometriosis is one of the rarer forms of extra pelvic endometriosis and represents less than 1% of the cases in the world [8,9]. Unlike most published accounts of umbilical endometriosis, this Ethiopian case incorporates ultrasound, his topathology, and cross-sectional imaging (CT) in the preopera t ive characterization of musculofascial invasion (linea alba and rectus sheath) and then proceeds with en bloc excision with defined margins (2 cm), fascial repair, and umbilicoplasty with structured nine-month recurrence-free follow-up, a pragmatic pathway feasible in resource-limited settings [1,4,8,10,11]. Our approach using a CT-guided plan and cosmetic restoration fol lowing margin-controlled resection is rarely emphasized in sub Saharan African literature, adding geographical and systems level relevance [1,4,6-8]. Clinical appearance and differential diagnosis Catamenial umbilical pain and swelling are the most consis tent clinical pointers for umbilical endometriosis, but umbilical hernia, pyogenic granuloma, epidermoid inclusion cyst, des moid tumor, and last but not least, Sister Mary Joseph’s nodule are all common misdiagnoses; the latter emphasizes the im portance of histologic exclusion of metastatic disease [4,5,18]. The presence of cyclicity symptoms, the absence of any previ ous surgery, and the imaging/cytology findings helped narrow down the workup and promoted a curative local approach in our case [1,4,8,11,16,17]. Primary vs. secondary disease and pathophysiology In the absence of a previous abdominal surgery, it is primary umbilical endometriosis developing presumably by lymphatic or hematogenous spread of endometrial cells [1,2,8,11], or em bryologic remnants’ metaplastic transformation as described in sub-analyses [3,5-7,9,10] and case series. Detection of the primary phenotype is important since it is often a local process of the abdominal wall that can be managed with local excision [4,8,10,11]. Imaging strategy Ultrasound is an easily accessible first-line modality that aids in defining lesion size and superficial extent in this patient; how ever, results are supportive and not pathognomonic [8,11,17]. FNAC offers a low-cost, preoperative tissue diagnosis, which is a valuable procedure that can reduce unnecessary exploratory procedures in which advanced imaging technology is limited [16]. In our experience, CT provided incremental value by defin ing invasion into musculofascial planes without intra-abdominal extension, thus informing the resection plane and the need for fascial repair when MRI was not available [4,8,10,11,17] Histopathology confirmation Microscopic examination revealed the classic features of endometriosis, including squamous epithelium with several variable-sized endometrial glands having columnar epithelium lining, compact endometrial stroma in the inner dermis, cysti cally dilated hemorrhagic spaces, dilated vessels, sheets of he mosiderin-laden macrophages, and free surgical margins. These results are diagnostic and help to rule out malignant mimics like metastatic adenocarcinoma [4,8,10,11,12,15]. Operative management, margins, and recurrence Surgical excision is still considered to be the definitive treat ment for umbilical endometriosis, with a low rate of recurrence when free margins are achieved and peritoneal extension is not present [8,10-12,15]. The 2cm circumferential margin used in the present case is consonant with a conservative margin-se cured approach warranted by fascial involvement disclosed by CT scan, which is consistent with case-based recommendations favoring wide local excision to reduce the risk of recurrence [4,8,11,12,15]. Umbilicoplasty was shown to be supportive of cosmetic and psychosocial results while not violating oncologic principles [4,10,11]. The patient’s uncomplicated recovery and disease-free status at 9 months are congruent with results re ported in series and reviews if margins are adequate and dis ease is outside of the peritoneal cavity [8,10-12,15]. Follow-up model and global health context In settings where routine postoperative MRI or further ad vanced surveillance is impractical, structured clinical follow up with review of symptoms and directed examination is a cost-effective method for the detection of early recurrence [8,10,11,13]. This is an example of a scalable approach: histo ry-weighted suspicion, basic imaging (ultrasound, CT—if avail able), FNAC (to provide tissue-level diagnosis), and definitive lo cal surgery (margins assured), providing cure and restoration of function, but within the constraints of health system resources [1,3,4,8,11,16,17]. Strengths: Corroborating multimodal diagnosis (US, FNAC, CT), clear operative detail (defined margin, fascial repair, um bilicoplasty), histologic confirmation, and longitudinal follow-up are among its strengths.

There is a lack of laparoscopy in our setup to comprehensively exclude concomitant pelvic disease; however, the lack of pelvic symptoms, lack of intra-abdominal exten sion on imaging, and recurrence-free course are suggestive of a localized nature in this primary umbilical endometriosis case [1,4,8,10,11]. As a single case report, generization of the study is limited. Umbilical endometriosis is a rare condition, but it should be considered in women of reproductive age with a history of cy clic umbilical pain and swelling. In low-resource settings, clini cal suspicion supported by ultrasound and histopathology can guide a timely excision with fascial repair and umbilicoplasty, resulting in a favorable outcome. Furthermore, the availability of basic surgical and pathology capacity and systematic clinical follow-up is also crucial in reducing diagnostic delay and the risk of recurrence. Patient perspective “I was concerned about the swelling for a long time. After surgery, the pain disappeared, and I feel relieved and healthy again.” Ethics: This case report meets the requirements of the Declaration of Helsinki. At our institution, approval of a single anonymized case report was not required by the institutional review board. Author contributions: Obsa Biratu conceived the idea and led the surgical management of the patient; Boka Imiru Shoro participated in the patient treatment and data collection; Tesfaye Hurges participated in the histopathologic diagnosis of the case; Senaf Alemu Fikadu and Berhanu Nigusse Bikila participated in data collection and Amanuel Mesfin Oljira participated in the patient management, manuscript writing and editing. All authors approved the final manuscript. Funding: No specific funding was received for this particular case report. Conflicts of interest: The authors state that there are no conflicts of interest. Abbreviations: UE: Umbilical Endometriosis; FNAC: Fine needle Aspiration Cytology; US: Ultrasound; CT: Computed Tomography; POD: Postoperative Day. - Asrat S, Tadesse N, Mohammed H, Mahamed B. Primary umbilical endometriosis: a case report and literature review. J Clin Med Health Care. 2024. - Tilahun T, Feyera J, Tamene M, Desalegn N, Oljira R. Coexistence of primary umbilical endometriosis and endometrial hyperplasia: a case report and review of the literature. Int Med Case Rep J. 2023; 16: 323–328. - Mesfin Kassa E, Weldetensaye EK. Review of laparoscopic gynecological procedures in Ethiopia: prevalence of endometriosis. World J Laparosc Surg. 2023. - Makena D, Obura T, Mutiso S, Oindi F. Umbilical endometriosis: a case series. J Med Case Rep. 2020; 14: 142. - Sabiri R, Gourja Y, Benrahal S, Houssin B, Sakher M, Samouh N. Umbilical endometriosis: a case report. Edorium J Gynecol Obstet. 2023; 7(2): 5–9. - Guindo B, Tall K, Kitha P, et al. Umbilical endometriosis: about a case at the Dermatology Hospital of Bamako. Cent J Dermatol Clin Res. 2024. - Okoro U, Darlinton-Peter Chibuzor U, Ortuanya K, et al. Primary umbilical endometriosis: a case report. Afr J Health Soc Sci. 2025; 2(2): 103–106. - Dridi D, Chiaffarino F, Parazzini F, et al. Umbilical endometriosis: a systematic literature review and pathogenic theory proposal. J Clin Med. 2022; 11(4): 995. - Dridi D, Buggio L, Donati A, et al. Clinical features and management of umbilical endometriosis: a 30-year monocentric retrospective study. Int J Environ Res Public Health. 2022; 19(24): 16754. - Li M, Zhang K, Liu C. Primary umbilical endometriosis: clinical aspects and long-term follow-up of five cases. J Int Med Res. 2025; 53(2): 1–10. - Bindra V, Sampurna S, Kade S, Mohanty GS, Madhavi N, Swetha P. Primary umbilical endometriosis – case series and review. Int J Surg Case Rep. 2022; 94: 107134. - Akhter F, Mallick R, Ball E. Umbilical endometriosis: case report and review of current management. Gynecol Res. 2018; 1(3): 72–74. - Tambovskaya V, Escalante L, Maldonado A, et al. Spontaneous umbilical endometriosis. Skin Health Dis. 2025; vzaf044. - Hamid A, Hajji M, Izig S, Soummani A. Umbilical endometriosis: a case report. Int J Adv Res. 2024. - Boesgaard-Kjer D, Kjer JJ. Primary umbilical endometriosis (PUE). Eur J Obstet Gynecol Reprod Biol. 2017; 209: 44–45. - Karthikeyan TM, Ajeeth Kumar CR, Veenaa NN, Thomas E. Cytological study of scar endometriosis: clinicopathological series with primary diagnosis by fine-needle aspiration cytology. Int J Adv Res. 2014; 2(12): 367–371. - Ciobanu S, Aipersbach S. Umbilical endometriosis. J Diagn Med Sonogr. 2011; 27(1): 33–36. - Gibson JAG, Thompson WR, Konamme S, Bhattacharya S. Sister Mary Joseph nodule: a diagnostic challenge. BMJ Case Rep. 2018; 2018: bcr-2017-223674.