Stage at diagnosis and treatment patterns among older women with breast cancer - An HMO and fee-for-service comparison

Context Few studies have compared patterns of care in health maintenance or ganization (HMO) and fee-for-service (FFS) settings. Objective To examine breast cancer stage at diagnosis and, for those at an early stage, treatment patterns for elderly women in HMO and FFS settings. Design Cancer registry data from the Surveillance, Epidemiology, and End Re sults (SEER) program linked to Medicare enrollment records. Settings and Participants Women aged 65 years or older residing in 11 geogr aphic areas who were newly diagnosed as having breast cancer between 1988 a nd 1993. Main Outcome Measures Standardized percentage of cases diagnosed at late st ages for HMO vs FFS; standardized percentage of early-stage cases undergoin g initial treatment with breast-conserving surgery (BCS); and, among BCS ca ses, standardized percentage receiving adjuvant radiation therapy. Standard ization was achieved through logistic regression, controlling for patient d emographics, cancer history, county of residence, year of diagnosis, and ed ucational attainment at the census tract level. Analyses of treatment patte rns were controlled for stage at diagnosis and tumor size. Results The HMO enrollees were less likely to have breast cancer diagnosed at late stages than FFS patients (HMO, 7.6%; FFS, 10.8%; difference, -3.2% [95% confidence interval (CI), -4.2% to -2.2%]). Among early-stage cases, t he percentages undergoing BCS were similar in HMO and FFS settings overall (HMO, 38.4%; FFS, 36.8%; difference, 1.6% [95% CI, 0.0%-3.2%]); percentages , varied markedly at the individual plan level. Among women undergoing BCS, HMO enrollees were significantly more likely to receive radiation therapy but, again, results varied by plan (HMO, 69.0%; FFS, 63.7%; difference, 5.3 % [95% CI, 2.9%-7.7%]). In general, use of BCS and radiation therapy was su bstantially higher than that found in an earlier study examining cases diag nosed between 1985 and 1989. Conclusions Treatment of early-stage breast cancer in HMOs often differs fr om local FFS patterns, but not in a consistent way. During the period of ou r study, elderly HMO enrollees did not appear to have systematic access pro blems with adjuvant radiation therapy following BCS compared with women in an FFS setting.