endometriosis is defined as the presence of functional endometrial tissue ( glands and stroma ) outside the normal uterine cavity . it affects 1015% of all women of reproductive age and 6% of the perimenopausal women . 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 . typical clinical presentation of umbilical endometriosis is a discrete bluish purple nodule in the umbilicus which becomes swollen , painful and bleeds concomitantly with menstruation . 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 . she denied having progressive secondary dysmenorrhea , abdominal pain , dyspareunia but complained of primary infertility for 3 years . 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 , 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 . 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 . after 6 months of follow - up , there was no sign of any local relapse . 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 . 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 . however , several other theories exist for the development of endometriosis including coelomic metaplasia , direct spread , iatrogenic dissemination , and lymphatic or hematogenous spread . 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 . 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 . 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 but , some authors have reported some success in relieving symptoms and reducing the size of the endometrial nodule using medical hormonal treatment . in the review of victory et al . , almost 70% of the patients required surgical management . 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 . local excision of the endometriotic lesion should be done obtaining an adequate rim of normal tissue all around in order to avoid local recurrence . 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
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 .