Clear cell degeneration associated with endometriosis of abdominal wall after cesarean section: A case report and systematic review of literature

Aim: The scar of cesarean section (CS) is the most common site of abdominal wall endometriosis (AWE), whose tumor degeneration has been reported in an increasing number of cases; the most frequent histological type is clear cell carcinoma (CCC). Methods: We conducted a systematic research of the literature, collecting data regarding the evidence on tumor degeneration from AWE after CS. Moreover, we reported a case of clear cell borderline tumor (CCBT) originating from AWE. Results: We included data of 37 patients with diagnosis of CCC. The average time between the last CS and the diagnosis of CCC was around 15 years. Overall, 26.0% and 73.9% patients received exclusive local abdominal resection of the lesion and additional surgery, respectively. Lymph nodes involvement was detected in 26.0 % patients and adjuvant chemotherapy was administered in 52.0 % cases. During follow-up period, 15.2% patients died of disease, 32.6% had no evidence of disease, and 17.4% recurred. We diagnosed a CCBT arose in a patients with AWE and a personal history of several surgical procedures for endometriosis, a CS and a subsequent transverse laparotomy. We performed an open bilateral ovariectomy and a large excision of the endometriotic abdominal lesion. Conclusion: Tumor degeneration from AWE seems to be a real occurrence with an increasing number of events. Considering the lack of risk factors and diagnostic instruments for tumor degeneration, the removal of AWE localization could be advisable, even though there was long average time between the trigger surgery and the tumor finding.