Primary mixed large cell neuroendocrine and high grade serous carcinoma of the endometrium.

Endometrial large-cell neuroendocrine carcinoma admixed with a high-grade serous (HGS) adenocarcinoma is extremely rare with only one reported case in the literature. We present the second reported case in a 47-year-old woman who presented with abdominal pain, distension and loss of weight. On examination she had a fixed pelvic mass and vascular left vaginal mass. Imaging confirmed a 13 cm solid cystic rectouterine pelvic mass, omental disease and retroperitoneal lymphadenopathy. She underwent a modified posterior exenteration, partial posterior vaginectomy, omentectomy and Hartmanns procedure with suboptimal debulking. Histopathology revealed a stage 4B mixed carcinoma with large cell neuroendocrine (70%) and HGS carcinoma (30%). Eight cycles of adjuvant cisplatin and paclitaxel were given with a complete radiological and biochemical response after 7 months. Unfortunately, she developed widespread recurrence at 9 month and was offered second line chemotherapy. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.