High-cost treatments for advanced lung cancer in Japan (Lung Cancer Study Group of the Japan Clinical Oncology Group).

Background: The treatment of lung cancer has made dramatic progress in the past decade, but due to the high cost of drugs, the total pharmaceutical cost has been rising explosively. There are currently no data available in Japan on which regimens are used, to what extent they are used, and what their total cost is.

Methods: Sixty Japanese centers belonging to the Lung Cancer Study Group of the Japan Clinical Oncology Group were surveyed for information about the first-line treatment for advanced lung cancer in practice from July 2021 to June 2022. Three types of cancer were included: driver gene mutation-negative NSCLC, EGFR mutation-positive NSCLC, and extensive-stage small cell lung cancer (ES-SCLC).

Results: Recent treatment costs for ICIs or ICI plus chemotherapy were about 20-55 times higher than those for conventional chemotherapy. Of the 3738 patients with driver gene aberration-negative NSCLC, 2573 (68.8%) received treatments with monthly cost of 500 000 Japanese yen (JPY) or more; 2555 (68.4%) received ICI therapy. Of the 1486 patients with EGFR mutation-positive NSCLC, 1290 (86.8%) received treatments with a monthly cost of 500 000 JPY or more; 1207 (81.2%) received osimertinib. ICI treatments with a monthly cost of 500 000 JPY or more were administered to 607 (56.3%) of 1079 patients with ES-SCLC. Elderly NSCLC patients received slightly more high-cost treatment than younger patients.

Conclusion: Recent treatments cost many times more than conventional chemotherapy. This study revealed that high-cost treatments were widely used in advanced lung cancer and some of high-cost treatments were used despite the lack of clear evidence. Physicians should pay attention to the cost of treatments they use.