A rare case of malignant transformation of endometrioma: A case report

Endometriosis of the abdominal wall, arising in a surgical scar, is a rare event. Its malignant transformation is an uncommon complication. We report a case of a suspected endometrioma in a caesarean section scar that was radically resected. The histopathologic diagnosis, surprisingly, was metastasis from papillary cystadenocarcinoma. A hysterosalpingo-oophorectomy was performed. One year later, she presented with a mass involving the left rectus abdominis muscle. Histopathologic re-evaluation revealed a carcinoma on endometriosis. A wide resection of the abdominal wall was performed, and reconstruction was undertaken with a Goretex mesh and two tensor fascia lata musculocutaneous flaps. Histopathological diagnosis was adenocarcinoma with invasion into the parietal peritoneum. Despite aggressive surgical treatment and adjuvant chemotherapy, 5 months after surgery, she presented peritoneal dissemination of the disease. The diagnosis of malignancy arising on endometrioma is often difficult because of the lack of pathognomonic signs. Prognosis is strictly related to the time of diagnosis. We believe that an early and aggressive treatment on the sole suspicion of an endometrial origin of an abdominal mass would allow a much earlier diagnosis and treatment for those patients, improving their prognosis, which is otherwise very poor. © 2010 Springer-Verlag.