Changes in the use and costs of diagnostic imaging among Medicare beneficiaries with cancer, 1999-2006.

Context: Emerging technologies, changing diagnostic and treatment patterns, and changes in Medicare reimbursement are contributing to increasing use of imaging in cancer. Imaging is the fastest growing expense for Medicare but has not been examined among beneficiaries with cancer.

Objective: To examine changes in the use of imaging and how those changes contribute to the overall cost of cancer care.

Design, Setting, And Patients: Analysis of a nationally representative 5% sample of claims from the US Centers for Medicare & Medicaid Services from 1999 through 2008. Patients were Medicare beneficiaries with incident breast cancer, colorectal cancer, leukemia, lung cancer, non-Hodgkin lymphoma, or prostate cancer.

Main Outcome Measures: Use and cost of imaging by modality, year, and cancer type.

Results: There were 100,954 incident cases of breast cancer, colorectal cancer, leukemia, lung cancer, non-Hodgkin lymphoma, and prostate cancer from 1999 through 2006. Significant mean annual increases in imaging use occurred among all cancer types for positron emission tomography (35.9%-53.6%), bone density studies (6.3%-20.0%), echocardiograms (5.0%-7.8%), magnetic resonance imaging (4.4%-11.5%), and ultrasound (0.7%-7.4%). Conventional radiograph rates decreased or stayed the same. As of 2006, beneficiaries with lung cancer and beneficiaries with lymphoma incurred the largest overall imaging costs, exceeding a mean of $3000 per beneficiary within 2 years of diagnosis. By 2005, one-third of beneficiaries with breast cancer underwent bone scans and half of beneficiaries with lung cancer or lymphoma underwent positron emission tomography scans. Mean 2-year imaging costs per beneficiary increased at a rate greater than the increase in mean total costs per beneficiary for all cancer types.

Conclusion: Imaging costs among Medicare beneficiaries with cancer increased from 1999 through 2006, outpacing the rate of increase in total costs among Medicare beneficiaries with cancer.