Background: Rectal neuroendocrine carcinoma is a rare disease with a prognosis worse than rectal adenocarcinoma. The
authors report a case of successful ultra-low anterior resection in well-differentiated neuroendocrine carcinoma of the lower
rectum.
Case Report: A 38-year-old man presented with chronic constipation for six years. Digital rectal examination, colonoscopy and pelvic MRI demonstrated a 5-cm. intramural mass with a smooth mucosa at the posterior aspect of the lower rectum; 4 cm above the anal verge. No liver metastasis was demonstrated by an abdominal CT scan. The patient underwent an uneventful ultra-low anterior resection. The operative time was 195 minutes and blood loss was 310 milliliters. The pathology report showed well-differentiated neuroendocrine carcinoma, presence of angio-lymphatic invasion and metastatic carcinoma in one out of twenty-six regional lymph nodes. The patient received postoperative adjuvant radiation and chemotherapy. No recurrent tumor was detected after 14 months of follow-up.
Conclusion: Although high recurrence rates are noted, radical oncologic resection followed by adjuvant chemo-radiation is a standard treatment in lower rectal neuroendocrine carcinoma. Long-term follow-up of this patient is still needed.

Keywords: Neuroendocrine carcinoma, Neuroendocrine tumor, NETs, Surgery, Rectum