Medical costs of lung cancer care in Japan during the first one or two years after initial diagnosis.

OBJECTIVES Japan's healthcare expenditures, especially on oncology, are rapidly growing; however, there are scant data on actual costs and cost-effectiveness in the real world. The aim was to assess the medical costs and outcomes of patients with advanced lung cancer. METHODS We retrospectively investigated all patients who were diagnosed with advanced lung cancer at the Japanese Red Cross Medical Center between 1 January 2008 and 31 December 2018. Patients were classified into three cohorts according to the year of diagnosis-Cohort 1: 2008-2010, Cohort 2: 2011-2014 and Cohort 3: 2015-2018-and assessed for medical costs and outcome. Medical costs were divided into outpatient and inpatient costs and were calculated on a monthly basis. RESULTS Ninety-five patients with small cell lung cancer (SCLC) and 330 with nonsmall cell lung cancer (NSCLC) were included. There was a trend toward increased costs during the first two years after diagnosis in NSCLC patients, without changes in monthly costs, reflecting improved survival. Compared to Cohort 1, Cohort 3 patients with NSCLC had longer survival (median: 24 versus 12 months, P < 0.001), with a median incremental cost of Japanese Yen 6 million during the initial two years. The proportion of outpatient costs increased over time, especially for NSCLC patients (P < 0.001). No changes in costs or survival were observed in SCLC patients. CONCLUSIONS In NSCLC patients, medical costs increased with prolonged survival during the last decade. The costs on a monthly basis did not change. The proportion of outpatient costs increased.