Rectal carcinoid tumour presenting as polyp: a challenge in management in rural settings

Abstract

Neuroendocrine tumours (NETs) are rare neoplasms that present with non-specific symptoms, with an increase in incidence and prevalence mainly due to increased endoscopic diagnoses. 1,2 Endoscopically, rectal NETs (rNETs) appear as rounded, smooth, mainly <10 mm polypoid lesions of normal mucosa, which makes them challenging to distinguish from other colonic polyps. 3 A 45-year-old asymptomatic Caucasian man was referred to a rural district hospital for a routine bowel screening with a background of first-degree family history of bowel cancer. He was fit and well and did not take regular medication.The first colonoscopy was performed in October 2015, revealing a pedunculated rectal polyp 10 cm from the anal verge without central depression or ulceration (Fig. 1a). The histopathology showed an NET measuring 15 mm, limited to the mucosa and submucosa, and appears 1.0 mm from the cauterized deep resection margin, with no lymphovascular invasion and Ki-67 <1% (Fig. 1b,c). Pelvic magnetic resonance imaging suggested a T3N0 rectal carcinoma (Fig. 1d). Computed tomography of the chest, abdomen and pelvis, ¶The tumour marker CEA. All hazard ratios are from the meta-analysis of Gonzalez et al. (2013). 5 CEA, carcinoembryonic antigen; ECOG, Easter Cooperative Oncology Group; FEV 1 , forced expiratory volume in the first second.