Management of 1- to 2-cm carcinoid tumors of the appendix: Using the national cancer data base to address controversies in general surgery

Background The management of 1- to 2-cm appendiceal carcinoid tumors remains controversial. Here we use the National Cancer Data Base (NCDB) to compare long-term outcomes for patients treated via resection of the primary tumor alone vs right hemicolectomy (RHC). Study Design The 1998 to 2011 NCDB User File was queried to identify patients with 1- to 2-cm appendiceal carcinoids. Patients were stratified by surgical technique: Resection of the primary tumor alone vs RHC with regional lymphadenectomy. Multivariable logistic regression was used to compare short-term outcomes. Survival was estimated using the Kaplan-Meier method with comparisons based on the log-rank test. Results A total of 916 patients were identified, including 42% managed with primary resection and 58% with RHC. Patients who underwent RHC had slightly larger tumors and higher-stage tumors; otherwise, there were no baseline differences between groups. The rates of positive margins were similar (5.5% vs 4.5%; p = 0.60). Among all patients, 1- and 5-year survival were 98.1% and 88.7% vs 96.7% and 87.4% (p = 0.52) for those managed via primary resection vs RHC, respectively. Among patients with moderate/high-grade/anaplastic carcinoids, 1- and 5-year survival were 93.3% and 72.0% vs 92.3% and 71.9%, respectively (p = 0.78). After adjustment with Cox proportional hazards modeling, we confirmed that there was no survival benefit for patients undergoing RHC (hazard ratio = 1.14; p = 0.72). Conclusions For 1- to 2-cm appendiceal carcinoids, formal resection of the right colon does not appear to improve survival, even for higher-grade tumors. Our findings suggest that resection of the primary tumor alone is adequate for all carcinoids <2 cm.