Comparison of chemotherapy for unresectable pulmonary high-grade non-small cell neuroendocrine carcinoma and small-cell lung cancer

BackgroundPulmonary large cell neuroendocrine carcinoma (LCNEC) shares several features with small cell lung carcinoma (SCLC). Most histologic diagnoses of LCNEC are currently obtained by surgical specimens. While the diagnosis of LCNEC by biopsy specimens is challenging, a definitive diagnosis of this highly malignant tumor is critical in unresectable cases to determine the optimal therapeutic strategy. The objective of this study was to assess the efficacy of chemotherapy for unresectable high-grade non-small cell neuroendocrine carcinoma (HNSCNEC) called by us, which likely includes most LCNECs except for combined types, and to compare the efficacy of chemotherapy for HNSCNEC, with that for extended disease SCLC (ED-SCLC).MethodsBetween September 2002 and October 2007, we reviewed 14 patients with HNSCNEC, which was defined using biopsy specimens according to histological and immunohistological criteria proposed by us. We simultaneously evaluated the clinical response to the chemotherapy and survival time of the 14 HNSCNEC and 77 ED-SCLC patients.ResultsThe chemotherapy regimens in the 14 patients with unresectable HNSCNEC were platinum-based combination regimens or irinotecan or vinorelbine or docetaxel alone. The chemotherapy regimens in the 77 patients with ED-SCLC were platinum-based combination regimens. We assessed an objective response rate, a one-year survival rate, and median survival time as 50% (7/14), 34% and 10 months, respectively, in the 14 HNSCNEC patients, and as 53% (41/77), 48% and 12.3 months, respectively, in the 77 ED-SCLC patients.ConclusionThe clinical efficacy of chemotherapy for unresectable HNSCNECs, including most LCNECs, is comparable to that for ED-SCLC.