Long-Term Outcome of Patients with Locally Resected High- and Low-Risk Rectal Carcinoid Tumors

Background: Tumor size and lymphovascular invasion are known high-risk factors for lymph node and distant metastasis in patients with rectal carcinoid tumors. However, the optimal treatment for these tumors remains controversial. Aim: The aim of this paper is to compare the outcome of local or radical resection between patients with high-risk (tumor size >10 mm or lymphovascular invasion) disease and those with low-risk (tumor size ≤10 mm, no lymphovascular invasion) disease. Methods: Patients with rectal carcinoid tumors treated between January 1990 and March 2010 were identified retrospectively and classified into low- and high-risk groups. Results: In total, 83 patients with rectal carcinoid tumors were included, 53 (64 %) of whom were identified as low-risk and 30 (36 %) as high-risk. Local resection was performed in 50 (60 %) low-risk and 24 (29 %) high-risk patients, and postoperative recurrence was observed in one (1 %) of the high-risk patients who underwent local resection and one (11 %) who underwent radical resection. No recurrence was observed in the low-risk group. Kaplan-Meier analysis of the patients who underwent local resection revealed that the 10-year disease-free survival rate was 100 % in the low-risk group and 83.3 % in the high-risk group. Conclusions: There was no significant difference in outcome between local and radical resection.