CASE OF THE MONTH
Neuroendocrine Carcinoma of the Uterus
64 year old female presenting with post-menopausal bleeding. MRI of pelvis showed dominant mass in the uterus measuring 7.7 cm. Endometrial biopsy showed cellular sheets of poorly differentiated malignant cells, positive for Pancytokeratin and patchy staining for PAX8. Resection specimen show a friable pink-yellow indurated mass filling in the endometrial cavity invading through the myometrium and involving the serosal surfaces. Sections of the tumor show sheets of monotonous high-grade tumor cells with high N:C ratio, homogenous chromatin with salt and pepper quality, high mitotic index and extensive areas of necrosis. Tumor cells were diffusely positive for Pan-CK, INSM-1, chromogranin and synaptophysin and negative for desmin, CD10, Bcl-2, vimentin, ER and HMB45. The diagnosis is high-grade neuroendocrine carcinoma of endometrial origin. Based on the morphology, it is difficult to ascertain whether it is a pure large cell, a pure small cell or a mixed large cell and small cell neuroendocrine tumor.
High-grade neuroendocrine carcinomas are highly aggressive rare tumors and frequently present at an advanced stage. Five-year survival for small cell neuroendocrine carcinoma of all stages is reported to be 14–39%, with poorer survival in higher stage disease {2,143,1161,1850}. The management of high-grade neuroendocrine carcinoma may include specific neuroendocrine-based systemic chemo-therapy and radiation therapy including axial sites.