Small-cell neuroendocrine carcinoma of the rectum — a rare tumor type with poor prognosis: A case report and review of literature

BACKGROUND: Small-cell neuroendocrine carcinoma (SNEC) of the rectum is a rare tumor associated with poor prognosis. CASE SUMMARY: We report a case of a 77-year-old male who came into our hospital because of blood with his stool. An endoscopy revealed a cauliflower-like neoplasm in his rectum. Imaging examination showed that the lesion in the upper rectum was likely rectal cancer, and there was no evidence of metastasis. The patient was treated with surgery. Pathological examination confirmed SNEC of the rectum and an R0 resection was achieved. However, 1 mo after the operation, the patient developed intestinal and ureteral obstructions due to peritoneal metastases. Finally, the patient died from renal failure. CONCLUSION: SNEC of the rectum is a high-grade carcinoma with an aggressive phenotype, and surgery should be cautiously considered.