BACKGROUND: Chemoimmunotherapy is widely used as the first-line treatment for extensive-stage small cell lung cancer (ES-SCLC), but treatment options for second-line have not changed. Amrubicin monotherapy is used as the standard treatment for relapsed SCLC, but since chemoimmunotherapy became an additional indication for ES-SCLC, the efficacy and safety of second-line amrubicin have not been sufficiently investigated. METHODS: We enrolled a total of 131 relapsed SCLC patients who received second-line amrubicin at eleven institutions in Japan between August 2019 and June 2023. We retrospectively examined the efficacy and safety of second-line amrubicin monotherapy. RESULTS: Twenty-five (19.1%) and 106 patients (80.9%) had sensitive and refractory relapse, respectively. 51 (38.9%) and 80 (61.1%) patients received first-line chemoimmunotherapy and first-line chemotherapy, respectively. The median progression-free survival (PFS) and overall survival (OS) were 3.6 months (95% confidence interval CI, 3.1-4.1 months) and 7.9 months (95% CI, 6.7-9.1 months), respectively. The median PFS and OS were significantly longer in the sensitive group compared with the refractory group (PFS: 6.4 vs. 3.5 months, p = 0.008, OS: 9.4 vs. 6.4 months, p = 0.021, respectively). Treatment-related adverse events were as follows: Grade 4 neutropenia in 51 patients (38.9%), grade 3 or higher febrile neutropenia in 18 patients (13.7%), and all grade interstitial lung disease in 13 patients (9.9%). Treatment-related death was 1 patient (0.8%). CONCLUSION: Second-line amrubicin monotherapy for relapsed SCLC may be useful and well-tolerated as a treatment option after first-line chemoimmunotherapy or chemotherapy.
Sonehara et al. (Fri,) studied this question.