Abstract
PURPOSE: To compare medical expenditures of patients receiving old and new colorectal cancer (CRC) regimens. STUDY DESIGN: USING CLAIMS DATA, WE IDENTIFIED TWO COHORTS OF PRIVATELY INSURED PATIENTS DIAGNOSED WITH CRC: first, those diagnosed before new treatment introduction (January 1, 2002, to December 31, 2002), and second, those diagnosed after new treatment introduction (June 1, 2004, to May 31, 2005). CRC diagnosis was identified using International Classification of Diseases-9 codes 153.xx, 154.xx, and 159.0. First- and second-line chemotherapy regimens were identified. Treatments and expenditures were then observed for up to 2 years after initial diagnosis. METHODS: We estimated multivariate models to measure changes in cost with changes in treatment regimen. Approval dates of new regimens were used as natural experiments. RESULTS: New regimens, such as fluorouracil, leucovorin, and oxaliplatin (FOLFOX), have rapidly replaced the most prevalent preperiod product (ie, fluorouracil/leucovorin). Changes in treatment have caused large increases in total expenditure, primarily through increases in chemotherapy prices. FOLFOX alone has increased total average cost by 14%. New treatments have not substituted other medical services; rather, they have indirectly raised costs through nonstandard regimen use and increases in second-line treatment use. We found no evidence that expenditure effects were driven by changes in follow-up duration. CONCLUSION: New CRC treatments have increased both regimen choice and expenditures. New regimens have primarily increased expenditures through direct treatment costs; we observed no offsetting expenditure reductions.