Risk factors and efficacy outcomes of early-onset severe neutropenia due to paclitaxel or nanoparticle albumin-bound paclitaxel combined with ramucirumab in advanced gastric cancer: a multicenter retrospective cohort study.

BACKGROUND

Paclitaxel or nanoparticle albumin-bound paclitaxel combined with ramucirumab (PTX/nab-PTX + RAM) is widely used as second-line chemotherapy for advanced gastric cancer (AGC), but severe neutropenia often develops with this regimen. Although previous studies have reported that severe neutropenia is a favorable prognostic factor in cancer chemotherapy, it is unclear in AGC patients receiving PTX/nab-PTX + RAM. In addition, the risk factors for early-onset of severe neutropenia (EOSN) still remain unknown.

METHODS

Among patients with AGC treated with PTX/nab-PTX (on day 1, 8, and 15) + RAM (on day 1 and 15) every 4 weeks as second-line therapy from January 2017 to June 2020, those with grade 0 or 1 neutropenia before the treatment were retrospectively studied. Blood tests were performed on the day of treatment each time, and disease progression was primarily determined by computed tomography every 8±2 weeks. EOSN was defined as grade 4 neutropenia that occurred during the first 28 days. The risk factors for EOSN were investigated using multivariate logistic regression analysis. Progression-free survival (PFS) and overall survival (OS) in patients with and without EOSN were investigated using multivariate analysis with a Cox proportional hazards model.

RESULTS

The clinical data of 244 patients were analyzed. EOSN was observed in 51 (20.9%) patients. Multivariate analysis identified the following five risk factors for EOSN: age ≥65 years [odds ratio (OR), 2.75], presence of primary tumor (OR, 2.82), presence of peritoneal metastasis (OR, 2.52), grade 1 neutropenia (OR, 3.32), and high serum level of alkaline phosphatase (OR, 2.34). The PFS was significantly longer in patients with EOSN than in those without EOSN [adjusted hazard ratio (HR), 0.61; 95% CI, 0.41-0.92] and the OS tended to be longer in patients with EOSN than in those without EOSN (adjusted HR, 0.73; 95% CI, 0.47-1.12). HR was adjusted with patient background factors and blood test data considered important as predictive or prognostic factors.

CONCLUSIONS

EOSN may be associated with favorable outcomes in patients with AGC treated with PTX/nab-PTX + RAM. We should carefully try to treat them keeping the risk factors in mind.