The Role of Adjuvant Chemotherapy in Non-Metastatic Goblet Cell Carcinoid of the Appendix: An 11-Year Experience from the National Cancer Database.

ABSTRACT

BACKGROUND: Goblet cell carcinoids (GCC) are an aggressive, albeit rare, subtype of appendiceal tumors that exhibit distinct histologic features and lack clear treatment guidelines. We aimed to ascertain the impact of adjuvant chemotherapy (AC) for GCC in a national cohort of patients. METHODS: Patients who underwent a right hemicolectomy for stage I-III GCC of the appendix between 2006 and 2016 were selected from the National Cancer Database (NCDB). Stratification based on AC receipt was performed. Kaplan-Meier survival estimates and Cox proportional hazard regression were used to identify predictors of overall survival (OS). RESULTS: A total of 867 patients were identified, of whom 124 (14%) received AC. Patients in the AC group were significantly younger (54 vs. 57 years; p = 0.006) and were predominantly of male sex (60 vs. 48%; p = 0.012). On histopathology, patients in the AC group had a higher proportion of poorly/undifferentiated grade (27 vs. 5%; p < 0.001), T4 disease (35 vs. 11%; p < 0.001), and lymph node-positive disease (45 vs. 7%; p < 0.001) than patients who did not receive AC. After excluding patients diagnosed in 2016 due to a lack of follow-up data (n = 162), a survival advantage for the AC group was detected only after stratification for lymph node-positive disease (p = 0.007). On Cox proportional hazard regression, AC demonstrated an independent association with improved OS (hazard ratio 0.24, 95% confidence interval 0.084-0.683; p = 0.007). CONCLUSION: The current analysis from the NCDB supports the role of AC for GCC of the appendix, chiefly for patients with lymph node metastatic disease.