Discordance with local guidelines for adjuvant chemotherapy in breast cancer: reasons and effect on survival.

Introduction: Adjuvant treatments are usually decided according to guidelines. However, many individual factors, such as performance status, patient refusal, complex interactions between factors (eg, discrepancies between grade and Ki 67), and complex clinical features (borderline age or tumor size) may introduce discrepancies. The aim of this study was to quantify discrepancies between local guidelines and patient management.

Patients And Methods: From 2003 and 2005, 581 consecutive patients underwent surgery for invasive breast cancer. Patient, tumor characteristics, and outcome were recorded. We compared patient characteristics according to whether local guidelines had been followed.

Results: In 90% of cases local guidelines were followed. Patients who inadequately did not receive chemotherapy were older (P < .0001), with positive hormonal receptor status (P = .02), and less aggressive tumors (P < .05). Main reasons for not administering chemotherapy were age, patient refusal, and micrometastatic node involvement. Patients from the other discordant group (ie, those who inadequately received chemotherapy), had larger (P = .01) and more aggressive tumors (P < .0001). In these cases, the clinical decision was mainly based on multifocal tumors and limit lower age. For disease-free survival (DFS), we found a significant difference between groups (P = .001). The best overall survival and DFS was found for patients who adequately received no adjuvant treatment. Survival among groups were similar when stratified on treatment modality.

Conclusion: The main reasons for discrepancy were age (advanced or lower limit), patient refusal, and multifocal tumors. In this series, deviations from recommendations had no affect on survival and raised the question of new indications for chemotherapy such as multifocal tumors.