From the Guidelines
For this 55-year-old gentleman with an 8 mm rectal carcinoid tumor confined to the submucosa with low mitotic rate, I recommend no further management (option 1). The patient has already undergone complete resection of the polyp, and the pathology findings are favorable. Rectal carcinoid tumors smaller than 1 cm with no evidence of invasion beyond the submucosa and low mitotic activity have an excellent prognosis with very low risk of metastasis (less than 2%) 1. Complete endoscopic resection is considered curative for these small, well-differentiated neuroendocrine tumors. The low mitotic rate (less than 2 per high-power field) indicates a low-grade tumor with minimal aggressive potential.
While some guidelines suggest surveillance colonoscopy in 1 year to ensure no recurrence, additional imaging studies or surgical intervention would represent overtreatment for this low-risk lesion. The patient should be informed about the generally excellent prognosis of small rectal carcinoids and reassured that complete resection has likely been curative. It's worth noting that the provided evidence primarily discusses gastric carcinoids and colorectal adenocarcinoma, but the principles of management for small, well-differentiated rectal carcinoids can be applied in this context, prioritizing a conservative approach given the low risk of metastasis and the curative nature of the endoscopic resection 2, 1.
Key points to consider in the management of this patient include:
- The size of the tumor (8 mm) and its confinement to the submucosa
- The low mitotic rate, indicating a low-grade tumor
- The completeness of the endoscopic resection
- The excellent prognosis for small rectal carcinoids with these characteristics
- The potential for overtreatment with additional imaging or surgical intervention.