Malignant transformation of abdominal wall endometriosis: A systematic review of the epidemiology, diagnosis, treatment, and outcomes.

Malignant transformation of abdominal wall endometriosis (AWE) is rare. The clinical characteristics and treatment of malignant transformation of AWE are not well known. Therefore, in this review, we performed a thorough search for malignant transformation of AWE on MEDLINE and Web of Science from their inception to May 2021. In total, the data of 46 patients with malignant transformation of AWE were retrieved, and all the data on these patients were collected. After reviewing and analyzing the clinical parameters, we found that cesarean scar was the most common site of malignant transformation of AWE, and the most common pathological type of malignant transformation of AWE was clear cell cancer, followed by endometrioid adenocarcinoma. The main symptoms of malignant transformation of AWE included an abdominal nodule or mass, and ultrasonography was the first choice for diagnosis. The most widely accepted treatment was surgical resection of local lesions with adjunctive chemotherapy and/or radiotherapy, and the overall survival of patients with malignant transformation of AWE was poor. In conclusion, malignant transformation of AWE is rare, and the prognosis is poor. Thus, improving abdominal surgical technology and avoiding iatrogenic ectopia and implantation of the endometrium are necessary to prevent malignant transformation of AWE.