Surgical management of breast cancer in Australian women in 1993: Analysis of Medicare statistics

Objective: To examine patterns of surgical management of breast cancer among Australian women. Design: Retrospective survey of Medicare records (a national dataset of all services rendered on a ''fee-for-service'' basis for which a Medicare benefit has been paid). Patients: All Australian women (4683) who underwent surgery consistent with being for breast cancer in 1993 and for which Medicare benefits were paid. Main outcome measures: Proportions of women undergoing different forms of mastectomy, breast-conserving surgery and axillary surgery by patient age and State and region (urban or rural) of residence. Results: Modified radical mastectomy was the most common surgery, performed in 2097 of the 4683 women (44.8%), while 1868 (39.9%) had breast-conserving surgery. Frequency of breast conservation decreased significantly with age and varied significantly between States and region of residence. It ranged from 34% in Western Australia to 49% in South Australia and the Northern Territory, and from 34% among rural women to 42% among urban women. Axillary surgery was recorded for 83% of all women studied. Conclusions: There was substantial geographical variation in patterns of surgical management for breast cancer. The tendency for rural women to undergo mastectomy rather than breast-conserving surgery may reflect the relative lack of access to postoperative radiotherapy. We are unable to explain the variation between States.