Umbilical endometriosis: a case series

Background: Endometriosis is the presence of endometrial tissue outside the uterine cavity. The lesions are typically found in the pelvic cavity but can occur in other extrapelvic areas. Umbilical endometriosis, also known as Villar’s node, is a rare disease comprising 0.5 –1% of all extrapelvic disease. It commonly presents with cyclical pain and bleeding from an umbilical nodule. Case series: We present a retrospective case series of five African patients with umbilical endometriosis diagnosed and treated between July 2015 and February 2019 at a tertiary health facility. The patients were aged between 31 and 47 years, and all presented with an umbilical swelling and pain. They had lesions with diameters ranging from 1.6 cm to 4 cm. The duration of symptoms ranged between 3 and 60 months. Their diagnoses were made on the basis of clinical presentation followed by surgical excision. In all the cases, diagnosis was confirmed by histopathology with no malignancy detected.

Umbilical endometriosis is a rare condition that should be considered as a differential diagnosis in women with umbilical lesions. Diagnosis is mostly clinical; most patients present with umbilical swelling, cyclical pain, and bleeding or discharge. Imaging has a limited role. Surgical excision is the treatment of choice with low risk of malignancy or recurrence.

Umbilical endometriosis, Umbilical swelling, Cyclical pain, Surgical excision

Endometriosis is the presence of endometrial tissue out- side the uterine cavity. It is a benign condition affecting 10–15% of women [ 1]. It classically affects women of re- productive age. The lesions occur mostly on pelvic sites involving the ovaries, uterosacral ligaments, ovarian fossa, cul-de-sac, and bladder in that order [ 2]. Extrapel- vic endometriosis occurs less commonly. The extrapelvic sites include the diaphragm, pulmonary, urinary tract, gastrointestinal tract, brain, and cutaneous endometri- osis. Umbilical endometriosis is rare, and it comprises 0.5–1% of all extrapelvic disease. Although rare, umbil- ical endometriosis is the commonest type of cutaneous endometriosis [ 3]. Umbilical endometriosis can be categorized as primary when it occurs spontaneously or secondary when it occurs following laparoscopic or open procedures, the latter being more common [ 4]. Primary umbilical endo- metriosis was first described by Villar in 1886; therefore, it is also known as Villar ’s nodule [ 5]. The pathogenesis of endometriosis is not well understood. Postulated the- ories include Sampson ’s theory of retrograde menstru- ation, which is the commonest, coelomic metaplasia, induction theory, embryonic Mullerian rests, bone mar- row stem cell theory, and hematogenous/lymphatic spread. The theory favored in the case of umbilical endometriosis is hematogenous/lymphatic spread where there is coexisting pelvic endometriosis. Isolated umbil- ical endometriosis could develop from metaplasia of ura- chal remnants [ 6]. The aim of this study was to evaluate the clinical characteristics, presentation, diagnosis, and management of umbilical endometriosis in view of the literature. © The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. * Correspondence: [email protected] Department of Obstetrics and Gynecology, Aga Khan University Hospital Nairobi, P.O. Box, Nairobi 30270-00100, Kenya Makena et al. Journal of Medical Case Reports (2020) 14:142 https://doi.org/10.1186/s13256-020-02492-9 Case series This is a retrospective, single-center, consecutive case series of African patients managed in a private tertiary health facility in Nairobi, Kenya. We reviewed five cases of patients with histology-confirmed umbilical endomet- riosis who were managed at Aga Khan University Hos- pital, Nairobi, between July 2015 and February 2019. The patients were reviewed in the gynecology clinic, where they presented with an umbilical swelling with cyclical pain and bleeding/discharge. A clinical evalu- ation based on history and physical examination was done, followed by surgical excision of the lesion. The specimen was taken for histological diagnosis, which confirmed umbilical endometriosis in all the cases. The diagnosis was made when there was identification of endometrial glands and stroma, areas of focal hemorrhage or chronic inflammation, and presence of macrophages with hemosiderin pigments. We analyzed age, parity, duration of symptoms, chief presentation, associated symptoms, size of the lesion, management, and histopathological diagnosis of the five patients included (Table 1). All the patients authorized informed consent in the medical records at admission. The clinical features and treatment details of the pa- tients are summarized in Table 1. The mean age of the patients was 40 years, with a range from 31 to 46 years. Two of the patients were nulliparous, and the other three had previous deliveries ranging from one to six de- liveries. None had a miscarriage. One of the patients had two previous cesarean deliveries, whereas the others had vaginal deliveries. No other previous abdominal surgeries were reported among the patients. The mean duration of symptoms prior to presentation was 21.4 months, with a range from 3 to 60 months. The preoperative diagnosis was clinical in all the cases (100%). The presentation was similar, with all having an umbilical swelling (100%), cyclical pain and bleeding in four of five (80%), with one having umbilical discharge instead of bleeding. Three of the patients reported asso- ciated symptoms of severe dysmenorrhea (60%), with one having heavy menses, too. One patient was being seen in follow-up for subfertility with bilateral tubal blockage. The largest dimension of the umbilical lesion (Fig. 1) ranged from 1.6 to 4 cm (mean 3.02 cm). One patient had preoperative imaging with magnetic resonance im- aging (MRI), which revealed a 1.6-cm umbilical lesion suggestive of umbilical endometriosis with normal pelvic findings. Another patient had a preoperative pelvic ultra- sound that revealed multiple intramural fibroids, the lar- gest about 3 cm, with a right ovarian simple cyst about 3 cm. The other three patients did not have any imaging. All patients had surgical excision of the lesion (Fig. 2) performed by a consultant gynecologist with a 1-cm safety margin up to the rectus fascia with closure of the umbilical defect. Three patients had additional surgery. One had laparoscopy and hysteroscopy due to dysmen- orrhea, which were normal. Another patient with subfer- tility, dysmenorrhea, and heavy menstrual bleeding had laparoscopy, where pelvic endometriosis was found with lesions on the uterosacral ligaments, right ovarian fossa, and posterior uterine wall, which were ablated. This pa- tient also had a total laparoscopic hysterectomy. The last patient had laparoscopy with ablation and excision of superficial endometriosis deposits on the anterior and posterior cul-de-sac. Histopathological examination was undertaken in all the specimens excised, and endometriosis was confirmed by identification of endometrial glands and/or stroma and recent hemorrhage in the dermis with no malig- nancy. All patients had uneventful postoperative recov- eries with no recurrence in follow-up. Table 1 Clinical features and treatment Patient Age (years) Parity Duration of symptoms (months) Chief presentation Associated symptoms Size of lesion in largest dimension (cm) Imaging Management Histology 1 33 0 + 0 8 Umbilical swelling, cyclic discharge No dysmenorrhea, normal flow 1.6 MRI Excision Confirmed 2 46 6 + 0 24 Umbilical swelling, cyclical pain, and bleeding – 4 – Excision Confirmed 3 47 1 + 0 60 Umbilical swelling, cyclical pain, and bleeding Dysmenorrhea, heavy menses 3.5 US Excision Confirmed 4 31 0 + 0 12 Umbilical swelling, cyclical pain, and bleeding Dysmenorrhea, normal flow 3 – Excision Confirmed 5 43 2 + 0 3 Umbilical swelling, cyclical pain, and bleeding Severe dysmenorrhea, normal flow 3 – Excision Confirmed MRI Magnetic resonance imaging, US Ultrasound Makena et al. Journal of Medical Case Reports (2020) 14:142 Page 2 of 4

and conclusions The average age of the five patients was 40 years, whereas that reported in the literature is 37.7 ± 0.98 years [ 4]. This indicates that endometriosis is an estrogen-dependent condition affecting premenopausal women of reproductive age [ 7]. The mean duration of the symptoms was 21.4 years, which is consistent with that in the literature of 17.8 ± 3.9 months [ 4]. Umbilical endometriosis can be primary if it occurs spontaneously or secondary following previous surgery, especially lap- aroscopic procedures with umbilical port entry. None of the five patients had a prior laparoscopic surgery; how- ever, one had two prior cesarean sections. Secondary umbilical endometriosis can occur following cesarean sections in 1% of cases [ 8]. The diagnosis is often made on the basis of clinical presentation, which was consistent with that reported in the literature. Most patients present with umbilical swelling with cyclical pain and bleeding. According to Victory et al. [4], umbilical swelling was present in al- most 90% of cases with less than 50% having bleeding and about 80% having pain. Pain is caused by tissue in- flammation, distention, and cyclical changes. The mean size of the lesion is about 2.29 cm, with color changes ranging from brown to blue, purple, black, and normal in decreasing order [ 4]. In our study, however, the color of the lesions was not reported. Discoloration occurs as a result of bleeding into the lesion with hemosiderin de- position, which can be seen at histopathological examination. Although preliminary diagnosis is made on the basis of history and physical examination, imaging may aid in preoperative evaluation. Ultrasound can be used to as- sess the nodule size and involvement of surrounding tis- sues and to evaluate other pelvic pathology, hence aiding the planning of surgical management [ 9]. One of the pa- tients had a pelvic ultrasound. In this patient, the ultra- sound features of umbilical endometriosis, which include isoechoic region with hyperechoic foci with or without abundant blood supply on Doppler [ 9], were not seen. However, other pelvic pathology, including intra- mural fibroids and ovarian cyst, were discovered. MRI can also be used as a method of preoperative evaluation in suspected endometriosis. It aids in evaluating pelvic endometriosis as well as to rule out other sinister differ- entials, including malignancy, Sister Mary Joseph nodule, and granuloma, among others. MRI features of an um- bilical endometriosis includes a homogeneous hypoin- tense lesion on T1-weighted sequence with low signals on T2 weighting [ 10, 11]. One of the patients in this study had an MRI scan with features of umbilical endometriosis. Up to 25% of umbilical endometriosis occurs with concurrent pelvic endometriosis. Two patients had coex- isting pelvic endometriosis treated at laparoscopy. Sub- fertility is a common condition among patients with endometriosis, occurring in up to 50% of women with endometriosis [ 1]. This phenomenon was reported in one patient in this study who was seen in follow-up for subfertility with bilateral tubal blockage. The umbilicus is a physiological scar that is a preferred site for umbilical endometriosis, as described by Yu et al. [11] Lymphatic and hematogenous spread to the umbilicus and direct extension of endometrial cells through round ligaments or omphalomesenteric rem- nants are possible theories to explain the etiology of um- bilical endometriosis [ 6, 12]. Surgical management is the treatment of choice [ 5, 12, 13]. Hormone therapy can be used preoperatively for Fig. 1 Hyperpigmented umbilical nodule Fig. 2 Surgical excision of umbilical endometriosis Makena et al. Journal of Medical Case Reports (2020) 14:142 Page 3 of 4 relief of symptoms, but it is not curative. It can also be used to reduce the size of large lesions prior to surgery. However, it is associated with side effects such as amen- orrhea [ 13]. Surgical excision was the treatment admin- istered to the patients in this study. These lesions have a low risk of malignancy and recurrence [ 4, 14]. Diagnosis is confirmed by histopathological examination. Umbilical endometriosis is a rare entity, especially when it occurs spontaneously. The clinical presentation of umbilical swelling, cyclical pain, and sometimes bleed- ing from the lesion are highly suggestive of this condi- tion. The treatment of choice is surgical excision, and diagnosis is confirmed by histopathological examination. Abbreviation MRI: Magnetic resonance imaging Authors’ contributions DM was responsible for drafting the article and for analysis and interpretation of the data. TO was involved in the management of the patients and discussed the cases. SM was involved in data acquisition and analysis and interpretation of the data. FO was involved in data acquisition and manuscript editing. All authors were involved in management and follow-up of the patients and revising the manuscript critically for important intellectual content. All authors read and approved the final manuscript. Funding None. Availability of data and materials Clinical data and complementary examinations are available from the corresponding author on reasonable request. Ethics approval and consent to participate For this case series, no ethical approval was sought. Informed consent was obtained from the patients, and their identity was concealed. Consent for publication Written informed consent was obtained from the patients for publication of the cases and any accompanying images. Copies of the consent are available for review by the Editor-in-Chief of this journal. Competing interests The authors declare no conflict of interest. Received: 25 May 2020 Accepted: 7 August 2020

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