Abstract
Amrubicin (AMR) is recommended for the treatment of recurrent small cell lung cancer (SCLC) in Japan, but neutropenia is frequently observed as an adverse effect. However, the relationship between severe neutropenia caused by chemotherapy and treatment response remains controversial in AMR. We examined the association between severe neutropenia induced by AMR and progression-free survival (PFS) in recurrent SCLC.
The study included 115 patients who started AMR at Hiroshima Citizens Hospital between July 2011 and June 2021. We defined Grade ≥ 3 as severe neutropenia, retrospectively investigated patient background, the cumulative number of courses with severe neutropenia among all courses (incidence rate of severe neutropenia), and PFS. Cox proportional hazards regression analysis revealed that the performance status of the Eastern Cooperative Oncology Group (hazard ratio (HR) = 2.503, P < 0.001), previous therapy (topoisomerase inhibitors) (HR = 1.758, P = 0.041), stage at diagnosis (HR = 1.746, P = 0.024), and incidence rate of severe neutropenia (HR = 1.636, P = 0.025) were factors significantly related to PFS. The patients were classified into the high and low groups based on the incidence rate of severe neutropenia, and we also extracted 27 cases each from the high and low groups using propensity score matching. A comparison of PFS in both groups showed that the high group had a significantly shorter PFS (P = 0.019).
Therefore, our findings suggest that management of neutropenia during AMR treatment in recurrent SCLC may contribute to prolonged PFS.
