Background: Various chemotherapy regimens for advanced colorectal cancer have been introduced to clinical practice in Japan over the past decade. The cost profiles of these regimens, however, remain unclear in Japan. To explore the detailed costs of different regimens used to treat advanced colorectal cancer during the entire course of chemotherapy in patients treated in a practical setting, we conducted a so-called "real-world" cost analysis.
Method: A detailed cost analysis was performed retrospectively. Patients with advanced colorectal cancer who had received chemotherapy in a practical healthcare setting from July 2004 through October 2010 were extracted from the ordering system database of Showa University Hospital. Direct medical costs of chemotherapy regimens were calculated from the hospital billing data of the patients. The analysis was conducted from a payer's perspective.
Results: A total of 30 patients with advanced colorectal cancer were identified. Twenty patients received up to second-line treatment, and 8 received up to third-line treatment. The regimens identified from among all courses of treatment in all patients were 13 oxaliplatin-based regimens, 31 irinotecan-based regimens, and 11 regimens including molecular targeted agents. The average (95% confidence interval [95% CI]) monthly cost during the overall period from the beginning of treatment to the end of treatment was 308,363 (258,792 to 357,933) Japanese yen (JPY). According to the type of regimen, the average monthly cost was 418,463 (357,413 to 479,513) JPY for oxaliplatin-based regimens, 215,499 (188,359 to 242,639) JPY for irinotecan-based regimens, and 705,460 (586,733 to 824,187) JPY for regimens including molecular targeted agents. Anticancer drug costs and hospital fees accounted for 50 to 77% and 11 to 25% of the overall costs of chemotherapy, respectively.
Conclusion: The costs of irinotecan-based regimens were lower than those of oxaliplatin-based regimens and regimens including molecular targeted agents in Japan. Using a lower cost regimen for first-line treatment can potentially reduce the overall cost of chemotherapy. The main cost drivers were the anticancer drug costs and hospitalization costs.