Is adjuvant chemotherapy beneficial for stage II-III goblet cell carcinoid/goblet cell adenocarcinoma of the appendix?

ABSTRACT

BACKGROUND: Goblet cell carcinoma (GCC), formerly known as goblet cell carcinoid, of the appendix constitutes less than 14% of all primary appendiceal neoplasms. Surgical resection is the main treatment and the role of adjuvant chemotherapy (AC) is not established. This study aims to evaluate the impact of AC in stage II-III appendiceal GCC. METHODS: Patients with pathological stage II and III GCC who underwent surgical resection between 2006 and 2015 were identified from the National Cancer Database (NCDB) using ICD-O-3 morphology and topography codes 8243/3 (goblet cell carcinoid) and C18.1. Patients treated with neoadjuvant systemic and/or radiation therapy and adjuvant radiation were excluded. Univariate and multivariable analyses were conducted, and Kaplan-Meier Curves were used to compare overall survival (OS) based on treatment received with Log-rank test. RESULTS: A total of 619 patients were identified. 54.4% males and 89.0% Caucasian; median age 56 (range, 23-90) years. Distribution across pathological stages II-III was 82.7% (N = 512) and 17.3% (N = 107) respectively. AC was administered in 9.4% (N = 48) of stage II and 47.7% (N = 51) of stage III patients. For stage II patients, AC was not associated with better OS in univariate (HR 0.32; 95% CI 0.04-2.34; p = 0.261) or multivariable analyses (HR 0.29; 95% CI 0.04-2.12; p = 0.221). By contrast, in stage III patients, AC was associated with better OS in univariate (HR 0.35; 95% CI 0.17-0.71; p = 0.004) and multivariable analyses (HR 0.25; 95% CI 0.07-0.88; p = 0.031). In the entire cohort 5-year OS for patients that received AC was 85.5% (74.0%, 92.1%) versus 82.7% (77.5%, 86.8%) (p = 0.801) with no AC. For stage II patients, 5-year OS was 96.9% with AC vs. 89.1% with no AC (p = 0.236). For stage III patients, 5-year OS was 77.1% with AC vs. 42.8% with no AC (p = 0.003). CONCLUSION: AC was associated with improved OS in patients with pathological stage III GCC of the appendix, but not with pathological stage II.