VARIATIONS IN BREAST-CONSERVATION SURGERY FOR WOMEN WITH AXILLARY LYMPH-NODE NEGATIVE BREAST-CANCER IN BRITISH-COLUMBIA

A population-based study was conducted including all women diagnosed i n British Columbia in 1991 with invasive node negative breast cancer ( n=942) in order to identify factors associated with variation in use o f breast conserving surgery (BCS) and to determine if provincial pract ice guidelines were followed. Patient, disease, treatment and physicia n-specific information was abstracted from medical records and origina l source documents. 413 (44%) patients received BCS (51% and 23% in su rgical candidates and non-candidates, respectively). Significant indep endent factors associated with BCS included patients' age, residence, family income, tumour size, tumour location, and extent of ductal carc inoma in-situ. Age and income had a significant interaction with stron ger income effects in older women. A strong surgeon effect was observe d which was not explained by measured surgeon attributes. Expansion of radiation treatment facilities may help address access issues. Furthe r examination of the patient-physician relationship and of ways to ass ist patients in decision making is needed.