Incidentally Detected Ileal Carcinoids During Colonoscopy: A Case Series

Abstract

Introduction: Incidentally detected small intestinal carcinoids are less frequently associated with distant metastasis when compared to symptomatic tumors. The importance of this cannot be understated because the impact of distant metastases on 5-year survival in these patients is quite dramatic (74% vs 40%). We report a series of 3 cases of small bowel carcinoid tumors incidentally detected at the time of ileal intubation during colonoscopy. Our first patient was a 74-year-old male with a family history of colon cancer in whom screening colonoscopy revealed a 2-cm submucosal lesion in the terminal ileum. Mucosal biopsies were negative for malignancy. Subsequently, an octreotide scan showed significant radiotracer uptake within the terminal ileal mass. He underwent a right hemicolectomy and surgical pathology demonstrated a low-grade pT2N1 malignant carcinoid with local mesenteric spread. He has now been disease-free for 2 years since the surgery. The second patient was a 46-year-old female who underwent a colonoscopy as part of her diagnostic work-up for iron-deficiency anemia. Colonoscopy revealed a 2-cm polyp in the terminal ileum. Mucosal biopsies revealed nests of neuroendocrine cells suspicious for a carcinoid tumor. Her octreotide scan was negative. A right hemicolectomy was successfully performed and surgical pathology revealed a 0.7-cm well-differentiated pT3N0 ileal carcinoid tumor. She is currently disease-free at 6 months of follow-up. Our third patient was a 45-year-old-female with a history of bilateral breast cancer status post bilateral mastectomy, who underwent a screening colonoscopy because of her increased risk of neoplasia secondary to positive BRCA 1 and 2 mutations. The colonoscopy revealed a firm, white, subcentimeter submucosal nodule in the terminal ileum. Mucosal biopsies were consistent with a neuroendocrine tumor and she underwent a successful ileocecectomy with ileocolic anastomosis. Surgical pathology revealed a pT1N0 well-differentiated ileal carcinoid tumor. She is doing well, with no recurrence of disease 18 months after her surgery. The usefulness of routine ileal intubation during colonoscopy is widely debated. Based on our cases, one could argue that it should be attempted in all cases. However, ileal intubation can be technically challenging and may inadvertently prolong colonoscopy procedure time. In view of the relative rarity of significant endoscopic findings in the terminal ileum in patients undergoing screening colonoscopy, the diagnostic yield and efficiency of ileal intubation in these patients should be studied in a large multi-center patient cohort.