Chemotherapy-induced neutropenia (CIN) reportedly indicated better prognosis for some cancers. We retrospectively analyzed 150 evaluable metastatic gastric cancer (MGC) patients who had received first-line EOF5 (combination regimen of epirubicin, oxaliplatin and 5-day continuous infusion of 5-fluorouracil) treatment. We divided patients into three groups according to the worst grade of CIN: absent group (grade 0), moderate group (grade 1-2) and severe group (grade 3-4). Multivariate analyses of overall survival (OS) proved moderate and severe CIN were important prognostic factors whether regarding CIN as a time-varying covariate (TVC) or not. Compared with absent CIN, hazard ratio (HR) for moderate and severe CIN were 0.31 (95% confidential interval (CI): 0.17-0.55; P < 0.001) and 0.36 (95% CI: 0.20-0.64; P = 0.001) respectively with TVC; and were 0.31 (95% CI: 0.17-0.56; P < 0.001) and 0.34 (95% CI: 0.19-0.61; P < 0.001) respectively without TVC. In progression-free survival (PFS) analyses, moderate and severe CIN showed similar results. In the landmark group (n = 122 patients) analyses with TVC, moderate and severe CIN remained prognostic factors for PFS, while only moderate CIN was prognostic factor for OS. CIN predicted longer OS and PFS in MGC patients treated with first-line EOF5 chemotherapy.
Keywords: EOF5 regimen; chemotherapy-induced neutropenia; metastatic gastric cancer; overall survival; progression-free survival.