Surgical Scar Endometriosis: An Emerging Enigma

Introduction Surgical scar endometriosis is a subtype of extra-pelvic endometriosis that is characterized by the formation of endometrial tissue near the incision site in patients who have previously undergone surgery. In recent times, with the increasing trend in Caesarean sections, the incidence of surgical scar endometriosis has also emerged. This study aims to describe the clinical characteristics and management of surgical scar endometriosis. Methodology We conducted this cross-sectional, observational study over eight years (2015-2022) in a tertiary care centre in Madurai district, Tamil Nadu, India. We conducted this study after acquiring an ethical certificate from the institutional ethics committee (IEC No. VMCIEC/22/2018). In this study, we sampled all women (n = 32) with a pathological diagnosis of scar endometriosis during the study period from hospital records (universal sampling). We searched the data for both general characteristics and lesion characteristics of the patients. The general characteristics include age, body mass index (BMI), parity, mode of delivery, symptoms, and imaging by ultrasound. We have recorded the lesion characteristics of the patient, including location and size of scar endometriosis, layers involved in scar endometriosis, and surgical technique from surgical notes written in the case sheet. The minimum sample size required for this study was 31 study subjects. We entered the data into Excel (Microsoft, Redmond, WA, USA) and analyzed it in SPSS version 21 (IBM Corp., Armonk, NY, USA). We expressed the quantitative variables in terms of mean and standard deviation and the qualitative variables in terms of frequency and percentage. Results The mean age of the study participants was 34 years (range 23-55 years). In our study, 29 patients (90.6%) were multi-para, and only three (9.4%) were nullipara. Among 29 parous women, the majority (25, or 77.7%) had delivered by Caesarean section, while only four (12.5%) delivered by normal vaginal delivery. The surgical procedures preceding the scar endometriosis were predominantly obstetric procedures (87.4%), out of which 25 patients underwent a Caesarean section and only three underwent an episiotomy. The most common presenting symptom of scar endometriosis in our study was cyclical pain in the scar site (90.4%), followed by swelling (81.25%). In 62.5% of patients, the duration between the presentation of surgical scar endometriosis and surgical intervention was greater than one year. Subcutaneous tissue (90.6%) was the most commonly involved layer in surgical scar endometriosis, followed by the rectus sheath (86.2%). The surgical procedure done for scar endometriosis was wide local excision in 78% of patients, and the remaining 22% of patients had wide local excision with mesh repair. Conclusion Cesarean section is an obvious risk factor for surgical scar endometriosis. Clinicians should have a high index of suspicion for surgical scar endometriosis in women presenting with cyclic pain at the scar site. Ultrasound is accurate in diagnosing scar endometriosis. Surgical management by wide local excision with a clear margin with or without mesh repair is the treatment of choice.