Dissemination of Clinical Results

OBJECTIVES: This study is an assessment of the extent to which clinical findings concerning mastectomy versus lumpectomy with radiation treatment have been disseminated in practice over time. METHODS: The authors examined the use of breast-conserving surgery followed by radiation therapy as an alternative treatment to mastectomy for early-stage breast cancer by analyzing 5 years (1986-1990) of inpatient and outpatient claims data from four insurers: Medicare, Medicaid, Blue Cross of Western Pennsylvania, and Pennsylvania Blue Shield. The 9,288 women who were eligible for either a lumpectomy or mastectomy during the study period represented approximately 90% of south western Pennsylvania's adult female population. Given the efficacy of both procedures, the authors expected a trend toward more BCS. RESULTS: By 1990, the use of lumpectomy increased significantly to 42.4% from 35.2%. The choice of lumpectomy was associated with younger women, private health insurance, absence of axillary node metastases, and treatment in urban hospitals. The authors also found, however, that only 45.3% of women with Medicaid coverage who had a lumpectomy during the study period received the requisite follow-up radiation therapy, compared with 77.5% of private insurance subscribers and 88.1% of Medicare beneficiaries. This finding is troubling even though there was substantially more compliance in the later years of the study, with 60.0% of eligible Medicaid beneficiaries receiving follow-up radiation therapy in 1990. CONCLUSIONS: This research illustrates the usefulness of administrative claims data in describing trends and practice patterns as well as the need for a different type of research to discover the reasons for the lack of compliance with treatment protocols by women or physicians.