A retrospective study of adjuvant albumin-bound paclitaxel plus S-1 after D2 gastrectomy versus oxaliplatin plus S-1 in gastric cancer

Adjuvant oxaliplatin plus S-1 (SOX) chemotherapy for gastric cancer (GC) after D2 gastrectomy has been proven effective. There has yet to be a study that evaluates adjuvant nanoparticle albumin-bound paclitaxel (nab-paclitaxel) plus S-1. In this single-center, retrospective study, GC patients after D2 gastrectomy received either nab-paclitaxel plus S-1 (AS group) or SOX group were recruited between January 2018 and December 2020 in The First Affiliated Hospital of Zhejiang University. Intravenous nab-paclitaxel 120 mg/m2 or 260 mg/m2 and oxaliplatin 130 mg/m2 were administered as eight 3 week cycle, especially in the AS and SOX group. Patients received S-1 twice daily with a dose of 40 mg/m2 in the two groups on days 1-14 of each cycle. The end points were disease-free survival (DFS) rate at 3 years and adverse events (AEs). There were 56 eligible patients, 28 in the AS group and 35 in the SOX group. The 3 year DFS rate was 78.0% in AS group versus 70.7% in SOX group (p = 0.46). Subgroup analysis showed that the patients with signet-ring positive in the AS group had a prolonged DFS compared with the SOX group (40.0 vs. 13.8 m, p = 0.02). The diffuse-type GC or low differentiation in the AS group was associated with numerically prolonged DFS compared with the SOX group, but the association was not statistically significant (p = 0.27 and p = 0.15 especially). Leukopenia (14.3%) were the most prevalent AEs in the AS group, while thrombocytopenia (28.5%) in the SOX group. Neutropenia (7.1% in AS group) and thrombocytopenia (22.8% in SOX group) were the most common grade 3 or 4 AEs. In this study analyzing past data, a tendency towards a greater 3 year DFS was observed when using AS regimen in signet-ring positive patients. AS group had fewer thrombocytopenia compared to SOX group. More studies should be conducted with larger sample sizes.