A Japanese lung cancer registry study on demographics and treatment modalities in medically treated patients

Abstract

This study provides the benchmark statistics on medically treated patients with non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) in Japan. Demographic background, treatment, and prognosis were obtained from patients with lung cancer pathologically diagnosed in 2012, who received nonsurgical treatment. Descriptive statistics and their associations with survival were analyzed. In total, 12 320 patients were registered from 314 institutions in Japan. The median age was 70 years, and 73% of the patients were male. The number (%) of stages I, II, III, and IV diseases were 468 (3.8%), 421 (3.4%), 3260 (26.5%), and 8171 (66.3%), respectively. NSCLC and SCLC accounted for 9872 (80.1%) and 2353 (19.1%) patients, respectively. Thoracic radiotherapy-based therapy, chemotherapy, and palliative care alone were administered to 2572 (20.9%), 7790 (63.2%), and 1952 (15.8%) patients, respectively. Clinical TNM stage was one of the strongest prognostic factors with the 3-year survival rates of 62.9%, 47.3%, 40.0%, 27.8%, 37.5%, 26.5%, and 18.2% for stages IA, IB, IIA, IIB, IIIA, IIIB, and IV, respectively. Among 6158 patients with NSCLC treated with chemotherapy, the 3-year survival rate was 33.4% in patients receiving epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) at some point in their clinical course, whereas it was 17.4% in patients who did not. The 3-year survival rate of SCLC was only 15.9%. In conclusion, approximately two-thirds of the patients were diagnosed as stage IV at the initial diagnosis. Use of EGFR-TKIs significantly improved the survival of patients with NSCLC.

Keywords: TNM stage; epidermal growth factor receptor; non-small cell lung cancer; small cell lung cancer; tyrosine kinase inhibitors.

FIGURE 1

Overall survival rate with regard to clinical M stage. Patients with M1a disease had a significantly better survival rate than those with M1b disease. The 3‐y survival rate was 23.3% vs 15.7%, respectively (P < .001). Blue line, M0; red line, M1a; and dark green line, M1b

FIGURE 2

Overall survival with regard to clinical TNM stage in patients with non–small cell lung cancer. There was no significant difference in survival between stage IIA and stage IIIA (P = .202) and between stage IIB and stage IIIB (P = .885). Navy line, stage IA; purple line, stage IB; dark green line, stage IIA; dark orange line, stage IIB; blue line, stage IIIA; red line, stage IIIB; and black line, stage IV

FIGURE 3

Overall survival with regard to histology. Red line, squamous cell carcinoma (Sq); black line, non‐Sq non–small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation; dark green line, non‐Sq NSCLC without EGFR mutation; dark orange line, non‐Sq NSCLC of unknown EGFR status; blue line, small cell lung cancer

FIGURE 4

Overall survival with regard to chief treatment through all lines. Patients who received concurrent chemoradiotherapy had better survival than those who received sequential chemoradiotherapy (3‐y survival rate, 43.6% vs 29.1%, respectively; P = .002). There was no difference in survival between patients who received sequential chemoradiotherapy and thoracic radiotherapy alone (3‐y survival rate, 29.1% vs 40.0%, respectively; P = .675). Red line, concurrent chemoradiotherapy; dark green line, sequential chemoradiotherapy; blue line, radiotherapy alone; dark orange line, chemotherapy; black line, palliative care alone

FIGURE 5

Overall survival in patients treated with chemotherapy. Red line, patients with non–small cell lung cancer (NSCLC) who received epidermal growth factor receptor‐tyrosine kinase inhibitor (EGFR‐TKI); blue line, patients with NSCLC who did not receive EGFR‐TKI; dark green line, patients with small cell lung cancer