Amrubicin monotherapy may be an effective second-line treatment for patients with large-cell neuroendocrine carcinoma or high-grade non-small-cell neuroendocrine carcinoma.

There is no standard chemotherapy for pulmonary large-cell neuroendocrine carcinoma (LCNEC) and this type of cancer is difficult to diagnose using biopsy specimens. At the Shizuoka Cancer Center, when small biopsy specimens are used, they are diagnosed as high-grade non-small-cell neuroendocrine carcinoma (HNSCNEC) and the patients are treated according to the small-cell lung cancer (SCLC) guidelines. Amrubicin is an effective second-line treatment for patients with SCLC, although it remains unclear whether amrubicin monotherapy is effective for patients with LCNEC or HNSCNEC. Between September, 2004 and December, 2013, 18 patients with advanced LCNEC or HNSCNEC received amrubicin monotherapy in the second-line setting. The efficacy and toxicity of this treatment were retrospectively assessed. A total of 6 patients had LCNEC and 12 patients had HNSCNEC. The patients included 13 men, and the median age was 66 years (range, 57-82 years). A total of 16 patients had an Eastern Cooperative Oncology Group performance status of 0 or 1. All the patients had received platinum-based chemotherapy as first-line treatment, and the median number of amrubicin cycles per patient was 4 (range, 1-9). The overall response rate was 11.1%. The median progression-free and overall survival were 4.0 and 9.1 months, respectively. Grade 3 or 4 neutropenia was observed in 44% of the patients, and grade 3 febrile neutropenia occurred in 17% of the patients. One patient developed pneumonia and succumbed to the disease. Non-hematological toxicities were generally mild and manageable. Therefore, the efficacy of amrubicin in the second-line setting for patients with LCNEC or HNSCNEC is limited. Development of new drugs and/or treatment strategies is warranted.