Japanese Lung Cancer Registry Study: First Prospective Enrollment of a Large Number of Surgical and Nonsurgical Cases in 2002

PurposeTo investigate prognoses of lung cancer patients prospectively enrolled in the Japan Lung Cancer Registry Study.MethodsPatients newly diagnosed as having lung cancer exclusively in 2002 were enrolled. Follow-up surveys were performed twice, in 2004 and 2009, and the final follow-up data with prognoses were analyzed for 14,695 patients (79%). Clinical stages were defined according to the sixth edition of the International Union Against Cancer-tumor, node, metastasis classification (2002).ResultsThe mean age was 67.1 years (range, 18-89 years), and there were 10,194 men (69.3%) and 4315 women (29.7%). The most frequent histology was adenocarcinoma (n = 8325, 56.7%), followed by squamous cell carcinoma (n = 3778, 26%) and small cell carcinoma (n = 1345, 9.2%). The distribution of clinical stages was as follows: IA, 4245 cases (29.3%); IB, 2248 (14.5%); IIA, 208 (1.4%); IIB, 918 (6.3%); IIIA, 1700 (11.8%); IIIB, 2110 (16.3%); and IV, 3037 (21.0%). The 5-year survival rates were 44.3% for all patients, 46.8% for those with non-small cell lung cancer, and 14.7% for those with small cell lung cancer. According to the clinical stage of non-small cell lung cancer and small cell lung cancer, the 5-year survival rates were 79.4 and 52.7% for stage IA, 56.9 and 39.3% for IB, 49.0 and 31.7% for IIA, 42.3 and 29.9% for IIB, 30.9 and 17.2% for IIIA, 16.7 and 12.4% for IIIB, and 5.8 and 3.8% for IV, respectively.ConclusionAnalysis of a large cohort in the Japanese registry study found that stage-specific prognosis was within a range similar to other reports. The data presented should provide an important reference for future clinical trials in Japan.