Second-line and third-line chemotherapy for lung cancer: use and cost.

OBJECTIVES: To identify commonly prescribed first-, second-, and third-line chemotherapy regimens for persons with lung cancer and to evaluate the utilization patterns and costs of care associated with receiving these regimens. STUDY
DESIGN: Retrospective data analysis.
METHODS: Using health insurance claims from January 1, 2002, through December 31, 2006, patients with lung cancer were identified by International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnosis codes. An algorithm was developed to identify first-, second-, and third-line chemotherapy. Patients were stratified by the number of discrete regimens received or by their specific chemotherapy agent or combination of agents. Data were analyzed for up to 2 years from the date of the initial first-line regimen and for 1 year from the second and third lines. Patient costs were based on total reimbursements for each group during the observation period.
RESULTS: Of patients receiving first-line chemotherapy, 25% and 10% received second-line and third-line chemotherapy, respectively. Docetaxel, gefitinib, and erlotinib hydrochloride were the most commonly prescribed second-line regimens; gefitinib and docetaxel were the most commonly prescribed third-line regimens. The most commonly prescribed second- and third-line agents changed substantially over time. Total costs and costs per patient per month increased as the number of lines of chemotherapy prescribed increased.
CONCLUSIONS: Second- and third-line chemotherapy is prescribed infrequently, and patterns of prescribing are changing over time. Direct medical care costs increase substantially with additional lines of therapy.