Epidemiology and clinical course of large cell neuroendocrine carcinoma of the lung: The Japanese lung cancer registry study.

BACKGROUND

This study aimed to investigate the characteristics and clinical courses of patients with pulmonary large cell neuroendocrine carcinoma (LCNEC) and compare the differences across lung cancer types.

METHODS

This prospective study included 11,310 patients with LCNEC, small cell lung cancer (SCLC), squamous cell carcinoma, and adenocarcinoma from the Japanese Joint Committee of Lung Cancer Registry (JJCLCR) database. The registry was opened in January 2012, and the follow-up was completed in April 2016.

RESULTS

In total, 80 patients (0.7 %) were diagnosed with LCNEC. LCNEC shared similar patient characteristics with SCLC, characterized by a median age of 68 years and a high prevalence of men (93.8 %) and smokers (97.5 %). In stage IV patients, the best overall response and disease control rates for first-line cisplatin-based chemotherapy were 34.8 % and 43.5 % for LCNEC but 60.6 % and 69.7 % for SCLC. Similarly, the overall response and disease control rates for first-line carboplatin-based chemotherapy in stage IV patients were 29.4 % and 41.2 % for LCNEC, but 56.1 % and 68.4 % for SCLC. The 3-year survival rates for LCNEC, SCLC, squamous cell carcinoma, and adenocarcinoma were 14.2 %, 15.9 %, 17.8 %, and 27.1 %, respectively. Kaplan-Meier curves of overall survival showed similarity between LCNEC and SCLC, with no statistical significance in the Cox hazard analysis (hazard ratio 0.818, 95 % confidence interval 0.611-1.096, p = 0.178).

CONCLUSIONS

Although patient characteristics and survival curves were similar in LCNEC and SCLC, our data demonstrate that LCNEC had inferior overall response and disease control rates in response to first-line chemotherapy compared to SCLC.