BREAST-CANCER SURVIVAL AND TREATMENT IN HEALTH MAINTENANCE ORGANIZATION AND FEE-FOR-SERVICE SETTINGS

Background: Enrollment in health maintenance organizations (HMOs) has increased rapidly during the past 10 years, reflecting a growing empha sis on health care cost containment. To determine whether there is a d ifference in the treatment and outcome for female patients with breast cancer enrolled in HMOs versus a fee-for-service setting, we compared the 10-year survival and initial treatment of patients with breast ca ncer enrolled in both types of plans. Methods: With the use of tumor r egistries covering the greater San Francisco-Oakland and Seattle-Puget Sound areas, respectively, we obtained information on the treatment a nd outcome for 13 358 female patients with breast cancer, aged 65 gear s and older, diagnosed between 1985 and 1992. We linked registry infor mation with Medicare data and data from the two large HMOs included in the study. We compared the survival and treatment differences between HMO and fee-for-service care after adjusting for tumor stage, comorbi dity, and sociodemographic characteristics. Results: In San Francisco- Oakland, the 10-year adjusted risk ratio for breast cancer deaths amon g HMO patients compared with fee-for-service patients was 0.71 (95% co nfidence interval [CI] = 0.59-0.87) and was comparable for all deaths. In Seattle-Puget Sound, the risk ratio for breast cancer deaths was 1 .01 (95% CI = 0.77-1.33) but somewhat lower for all deaths. Women enro lled in HMOs were more likely to receive breast-conserving surgery tha n women in fee-for-service (odds ratio = 1.55 in San Francisco-Oakland ; 3.39 in Seattle). HMO enrollees undergoing breast-conserving surgery were also more likely to receive adjuvant radiotherapy (San Francisco -Oakland odds ratio = 2.49; Seattle odds ratio = 4.62). Conclusions: L ong-term survival outcomes in the two prepaid group practice HMOs in t his study were at least equal to, and possibly better than, outcomes i n the fee-for-service system. In addition, the use of recommended ther apy for early stage breast cancer was more frequent in the two HMOs.