Perineal scar endometriosis

Endometriosis is defined as the presence of endometrial tissue outside the uterus and is common in fertile women.[] Pelvis is the most frequent location of the endometriosis. Endometriosis has been reported on the peritoneal and serosal surfaces of the intraabdominal organs in the pelvis such as ovaries, fallopian tubes, peritoneum, and rectovaginal septum.[] In addition, extrapelvic endometriosis has been reported in any region of the body including bowel, bladder, lung, kidney, extremities, perineum, and umbilicus.[] Approximately 5% of all cases of endometriosis are located in the intestinal tract and the intestinal tract is the most common site of the extrapelvic location of the endometriosis.[] The etiology and pathogenesis remain controversial. There are different theories about its histogenesis: the implant theory, the metaplasia theory (ovarian, tubal and cervix localization), the vascular theory (pulmonary and umbilical localization), and the macrophagic theory, which gives more importance to the immunological factor in the pathogenesis and details how the endometrial tissue penetrates into the peritoneal cavity by retrograde menstruation and stimulates macrophage migration. Growth factors released by macrophages are able to stimulate epithelial growth if the endometrial cells express the receiver. We present a case report of a patient with an endometriotic nodule located at the episiotomy scar at the right postlateral aspect of anal verge extending up to the right superolateral vaginal wall and medially into the anal sphincter. CASE REPORT A 35-year-old married female patient presented with perianal swelling and cyclic pain in the region of swelling since last 10 years. She gave history of undergoing lateral internal sphincterotomy 3 years back. The pain was refractory to analgesics (diclofenac and paracetamol). The pain was cyclic and progressive and related to the patient's menstrual history. The patient also gave a history that the swelling becomes more prominent during her menstrual periods. The anal sphincter function of the patient was normal. The patient had personal or family history of endometriosis or other obstetrical or gynecological adverse events. The patient had total of three children, first one born in 2004, the second one born is 2006, and third one born in 2007. The patient had episiotomy during all three childbirths. On local examination (Photograph 1), on inspection, there was a visible episiotomy scar on the right side of the perineal body, also a visibly prominent nodule on the right superolateral aspect of anal verge about 2 cm away from anal margin. On palpation, a firm nodule was palpated in episiotomy scar, measuring about 3 cm × 4 cm. This nodule was fixed and slightly tender at the time of examination as shown in figure 1. All baseline investigations were normal with beta-human chorionic gonadotropin levels of 0.15 mIU/ml, CA 125 levels of 124 IU/ml, and carcinoembryonic antigen levels of 0.15 mIU/ml. CEMRI was done which revealed T2-weighted axial image shows an oval hypointense lesion in subcutaneous tissue in the perianal region, T1-weighted sagittal images showing an isointense lesion with interspersed hyperintense foci in the subcutaneous tissue of the perineal region. Gadolinium-enhanced T1-weighted axial image revealed enhancement of lesion as shown in figure 234. With these imaging characteristics, possibility of scar endometriosis or dense fibrosis in the surgical scar was made. The patient was operated upon under central neuraxial block. The swelling was excised in toto along with some overlying skin tissue. Intraoperative findings revealed that a 2 cm × 3 cm hard swelling in the right perianal region with extensions superiorly up to postvaginal wall and medially into the external anal sphincter as shown in figure 5. The surgical wound was closed back primarily with a glove drain in place. Glove drain was removed on the morning of the 1st postoperative day (POD). The patient was discharged on the 3rd POD and gonadotropin-releasing hormone analogs were prescribed. The patient is on our regular follow-up in which she reported improvement in her symptoms. On gross examination of the surgical specimen, characteristics of endometriosis foci compatible with the endometrial tissue were found. On histological examination, section revealed squamous-lined epithelium with underlying subepithelium showing variable sized skeletal muscle fibers embedded within which are islands of endometrial glands and stroma, some of which are dilated along with mild inflammatory infiltrate, features consistent with scar endometriosis as shown in figure 6.

Endometriosis is a disorder resulting from the presence of actively growing and functioning endometrial tissue, both glandular and stromal, in sites outside the uterus. In 1897, Pfannenstiel reported the case of a patient with aberrant endometrium that involved the rectovaginal septum.[] In 1922, Blair Bell, in noting a series of cases of aberrant endometrium, first used the terms endometriosis and endometrioma, the former for the disease, the latter for the individual cystic lesion.[] Perineal endometrioma is a special situation in which implantation of viable endometrial cells occurs in episiotomy incisions. A tender nodule producing cyclic symptoms at the site of an episiotomy is highly suggestive of the diagnosis.[] As with other benign and malignant conditions in the area, endoanal ultrasound has been employed for its assessment.[] Local excision is the preferred treatment, although suppressive therapy may be employed. Patients harboring involvement of the anal sphincter have been managed successfully by wide excision and sphincteroplasty.[] Scar endometriosis is a rare entity reported in gynecological literature and presents in women who have undergone a previous abdominal or pelvic or perineal surgery.[] The incidence has been estimated to be only 0.03%–0.15% of all the cases of endometriosis.[] The incidence of perineal scar endometriosis is much rear. The diagnosis of scar endometriosis is difficult and challenging. Cyclic changes in the intensity of pain and size of endometrial implants during menstruation are usually characteristic of classical endometriosis. However, it is reported[] that only 20% of patients exhibit these symptoms. Patients usually complain of tenderness to palpation and raised, unsightly hypertrophic scar. Management includes both surgical excision and hormonal suppression.[] Oral contraceptives and progestational and androgenic agents have been tried. It is believed that hormonal suppression is only palliative and surgical excision of the scar is definitive treatment.[]

Scar endometriosis is a rare condition and should be suspected when a female in reproductive age presents with cyclic pain and swelling at the scar site after obstetric surgery. Surgical excision is treatment of choice as medical management is usually only palliative. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

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