Highly aggressive neuroendocrine neoplasm of the ascending colon: a wolf in sheep's clothing.

Neuroendocrine neoplasms represent a broad group of uncommon tumours, comprising neuroendocrine tumours, mixed neuroendocrine non-endocrine neoplasms and neuroendocrine carcinomas. While most neuroendocrine neoplasms are well differentiated and exhibit indolent disease biology with excellent treatment response, neuroendocrine carcinomas represent a rare subtype with much more aggressive tumour behaviour, minimal response to adjuvant therapy and extremely poor prognosis. Herein, we report the case of a 47-year-old man who presented with a phlegmonous ascending colonic mass and associated calcified ileocolic lymphadenopathy. He underwent emergent right hemicolectomy, which diagnosed a T4aN2b neuroendocrine carcinoma. Within a week the patient displayed rapidly progressive locoregional nodal disease and he succumbed to disease within 5 weeks. We discuss the significance of calcified abdominal lymphadenopathy on computed tomography scans of the abdomen and review the literature surrounding this rare and highly fatal malignancy.