Appropriateness of adjuvant systemic therapy for axillary node-negative breast cancer: a physician opinion survey

To examine variations in physicians' recommendations for systemic adjuvant therapy in the treatment of women with node-negative breast cancer (NNBC) and to determine factors used in making specific recommendations.

A questionnaire was sent by mail to all 149 Ontario physicians who actively treated breast cancer in 1993. The questionnaire described 48 clinical scenarios of women with NNBC, which included all possible combinations of the following factors: menopausal status, tumor size, hormone receptor status, histologic and nuclear grade, and lymphatic and/or vascular invasion. Respondents rated the appropriateness of administering tamoxifen, combination chemotherapy, or both tamoxifen and combination chemotherapy on a nine-point scale from extremely inappropriate to extremely appropriate. Respondent agreement and disagreement were tabulated for each scenario, and factors associated with specific treatment ratings were analyzed by logistic regression.

The response rate was 87%. Agreement for the appropriateness of specific therapies was most evident where clinical trials have demonstrated efficacy, whereas disagreement was observed in scenarios in which support for a specific treatment is not available in the current literature. Relevant tumor- and patient-specific factors were used in decision-making; personal characteristics of the respondents had no statistically significant impact on appropriateness ratings.

The physicians surveyed had good knowledge of NNBC prognostic factors, but had a range of opinion on optimal therapy for many clinical scenarios, which reflects current knowledge of the benefits of adjuvant therapy for NNBC.