Malignant transformation of persistent endometriosis after hysterectomy

The malignant transformation of persistent endometriotic implants into endometrioid adenocarcinoma is rare, especially after remote hysterectomy and salpingo-oophorectomy (TAH-BSO), and there are few cases reported in the English language literature. Patients receiving estrogen replacement therapy are common among the reported cases. We present a case that demonstrates the possibility of malignant transformation in a 53-year-old female, known case of endometriosis, who underwent total abdominal hysterectomy and bilateral salpingo-oophorectomy with no evidence of malignancy in the final pathology report. After 9 years, she presented with lower abdominal mass, and histopathological studies confirmed the diagnosis of well-differentiated endometrioid adenocarcinoma. The possibility of malignant transformation and possible risk factors are discussed with a brief literature review.