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

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.

Retrospective data analysis.

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.

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.

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.