Retrospective comparison of nab-paclitaxel plus ramucirumab and paclitaxel plus ramucirumab as second-line treatment for advanced gastric cancer focusing on peritoneal metastasis

Background Ramucirumab (RAM) plus solvent-based (sb)-paclitaxel (PTX) is the standard second-line chemotherapy for advanced gastric cancer (AGC). The subset analysis of the ABSOLUTE trial, which confirmed non-inferiority of weekly nanoparticle albumin-bound (nab)-PTX to weekly sb-PTX, suggested that nab-PTX might have better efficacy than sb-PTX in patients with peritoneal metastasis. We retrospectively evaluated the efficacy and safety of RAM plus sb-PTX and nab-PTX in patients with peritoneal metastasis of AGC. Methods AGC patients who received RAM plus sb-PTX or nab-PTX as second-line chemotherapy from June 2015 to February 2019 were included in the study. Overall survival (OS), progression-free survival (PFS), response rate, and safety were assessed. Results A total of 128 patients were included in this study (93 in the RAM plus sb-PTX group and 35 in the RAM plus nab-PTX group). PFS was 4.1 months in the RAM plus sb-PTX group and 4.6 months in the RAM plus nab-PTX group (HR 0.90; 95%CI 0.58-1.41, p = 0.643). OS was 8.9 months in the RAM plus sb-PTX group and 11.4 months in the RAM plus nab-PTX group (HR 0.95; 95%CI 0.56-1.62, p = 0.847). A total of 62 and 31 patients had peritoneal metastasis in the RAM plus sb-PTX and the RAM plus nab-PTX groups, respectively. RAM plus nab-PTX showed a slightly longer survival compared to RAM plus sb-PTX in patients with peritoneal metastasis (PFS 5.8 vs 3.5 months, HR 0.66; 95% CI 0.40-1.10, p = 0.109). Conclusion This study suggests that RAM plus nab-PTX might be a more effective treatment for peritoneal metastasis of AGC.