Metastatic neuroendocrine carcinoma of the colon: response to standard colorectal therapy

Abstract

Colorectal neuroendocrine carcinoma (NEC) is a rare disease. There are no prospective randomized studies evaluating the best approach for these patients. Colorectal NEC is frequently treated in a similar way to small-cell cancers, because of its histologic appearance. We report a case of metastatic colorectal NEC which was treated with standard chemotherapy for metastatic colonic adenocarcinoma, including biological agents. A 47-year-old woman, with an unremarkable past medical history, presented to the emergency room complaining of a five-day history of abdominal distension, diffuse crampy pain, and vomiting. An abdominal computed tomography scan showed an obstructive tumor in the descending colon associated with multiple focal hepatic lesions. On the same day, she underwent an emergency laparotomy. A histologic examination revealed a tumor composed of malignant small and medium-sized cells with scant cytoplasm and immunoreactivity to chromogranin and synaptophysin consistent with a diagnosis of NEC. Six out of 20 excised lymph nodes were compromised, and a biopsy of the hepatic lesion showed similar features to the primary tumor. She later received palliative chemotherapy with 5-fluorouracil/leucovorin plus oxaliplatin (FOLFOX) and bevacizumab every other week, completing six cycles. At the end of the treatment she showed clinical improvement and partial response by imaging studies without significant toxicities. We empha-size the report on the treatment received by this patient and the need for further investigation on this matter.