Primary umbilical endometriosis: A rarity.

Endometriosis is a functional endometrial tissue found outside the normal uterine cavity. Primary umbilical endometriosis is defined as the presence of ectopic endometrial glands and stroma within umbilicus, without prior history of pelvic endometriosis. It is a rare presentation in all cases of endometriosis, especially in Asians. Here, a case of primary umbilical endometriosis has been reported in a 33-year-old nulliparous female who presented with the history of cyclical bleeding and pain in an umbilical mass during menstrual cycle. Athough the disease is rare, umbilical endometriosis should be taken into account in differential diagnosis of umbilical disorders even in young nulliparous women with no typical symptoms of pelvic endometriosis. The disease pathogenesis, its symptoms, and treatment modality have been discussed.

INTRODUCTION

Endometriosis is defined as the presence of functional endometrial tissue (glands and stroma) outside the normal uterine cavity. It affects 10–15% of all women of reproductive age and 6% of the perimenopausal women.[12] More commonly, cutaneous endometriosis occurs in surgical scars including hysterotomy, cesarean section, laparoscopy, and episiotomy. However, primary umbilical endometriosis is a rare entity and is not related to surgical procedure. Incidence is stated about 0.5% to 1% of all cases of extragenital endometriosis.[3] Typical clinical presentation of umbilical endometriosis is a discrete bluish purple nodule in the umbilicus which becomes swollen, painful and bleeds concomitantly with menstruation.

CASE REPORT

A 33-year-old nulliparous female married for 4 years, attended our outpatient department (OPD), complaining of umbilical nodule which was first noticed 12 months back, slowly increasing in size. She also gave the history of cyclical bleeding and pain during menstrual cycle for last 8 months. Her medical and surgical histories were unremarkable. She denied having progressive secondary dysmenorrhea, abdominal pain, dyspareunia but complained of primary infertility for 3 years. She had regular menstrual cycle and no history of oral contraceptive pill intake. Physical examination revealed a dark-colored tender nodule of about 3 cm × 2 cm size, located in the umbilical fold [Figure 1]. On the basis of history and clinical examination, umbilical endometriosis was suspected and the patient was advised for re-examination during her menstrual period. At the second examination during her menstrual cycle, the umbilical nodule appeared more tender with evidence of recent bleeding. Ultrasound of abdominal parietesconfirmed a heterogenous hypoechoic mass in umbilical region of (2.2 cm × 3.2 cm) not extending to abdominal cavity or rectus sheath or muscle. Diagnostic laparoscopy was done at our department which ruled out associated pelvic endometriosis. Surgical excision was performed after proper counseling and consent [Figure 2]. The preoperative hemogram, biochemistry and coagulation profile was normal. The existing lesion was excised together with umbilicus under spinal anesthesia and postoperative period was uneventful. Histopathological examination of the excised specimen shows epidermis and subepidermal fibrous tissue, in which endometrial glands and hemosiderin laden macrophages are present. The features along with the clinical details were suggestive of umbilical endometriosis. After 6 months of follow-up, there was no sign of any local relapse.

Figure 1

Endometriotic nodule before removal

Figure 2

Excised umbilicus with nodule

DISCUSSION

Endometriosis involving the abdominal wall is termed as cutaneous endometriosis. Cutaneous variant of endometriosis is much rarer and has been reported to account for approximately 1% of all cases and is commonly associated with surgical scar. Primary umbilical endometriosis was first described by Villar. Clinically the lesion appears as firm nodule of varying size from few mm to cm. Cyclical pain and palpable mass is the most common presenting symptoms. Although the etiology is not completely understood but several theories have been postulated how endometrial tissue migrates from uterus to skin. Sampson hypothesized in 1920 that endometriosis results from retrograde menstruation through the fallopian tube into the pelvis.[4] However, several other theories exist for the development of endometriosis including coelomic metaplasia, direct spread, iatrogenic dissemination, and lymphatic or hematogenous spread.[5] The theory of lymphatic and hematogenous spread is favored in the case of umbilical endometriosis with coexisting pelvic endometriosis. However, it is believed that the disease might arise through the metaplasia of urachus remnant in case of isolated umbilical endometriosis.

The differential diagnosis of umbilical endometriotic lesions include pyogenic granuloma, umbilical polyps, melanocytic nevus, seborrhoeic keratosis, hemangioma, desmoids, and granular cell tumor.[67] Malignant lesions like melanoma, adenocarcinoma, squamous and basal cell carcinoma should be ruled out. Omphalitis, keloid, umbilical hernia, and foreign body granuloma are other differential diagnosis.

The highlights of the case described herein, is that the patient had primary or spontaneous umbilical endometriosis, i.e. the presence of ectopic endometrial tissue located in the umbilicus in the absence of previous surgery for either gynecological disorder or cesarean incision. In the view of Victory et al. the mean age at diagnosis was 37.3 years.[8] Notably, the patient of the present case was of 33 years. Interestingly, the majority of the patients with umbilical endometriosis do not report a history of pelvic endometriosis, as in the patient described in this report. Management of umbilical endometriosis has not been standardized due to scarcity of cases. In general, medical management using progesterone, danazole, norethisterone, and gonadotropin-releasing hormone (GNRH) analogue has not shown reliable result. But, some authors have reported some success in relieving symptoms and reducing the size of the endometrial nodule using medical hormonal treatment.[27] In the review of Victory et al., almost 70% of the patients required surgical management.[8] The operative options are 1) complete umbilical resection with or without repair of underlying fascia and peritoneum 2) local excision of endometrial nodule, sparing the umbilicus. Total removal of the umbilicus is the most preferred operation for umbilical endometriosis. Local excision of the endometriotic lesion should be done obtaining an adequate rim of normal tissue all around in order to avoid local recurrence.[27] Some authors recommended whole umbilical excision irrespective of the size of the endometrial nodule.[910] We decided for radical treatment based on the size of the nodule and to exclude the possibility of local recurrence. During the follow-up of the reported patient after 6 months of surgery, there were no signs or symptoms of local recurrence.