Establishing treatment benchmarks for mammography-screened breast cancer population based on a review of evidence-based clinical guidelines.

BACKGROUND. No benchmarks exist in the screened breast cancer population to establish the optimal proportions of newly detected cancer patients who should receive the ideal treatment. The aim of the study was to estimate the optimal proportion of cases diagnosed in a breast-screening program who should receive treatment according to evidence-based cancer treatment guidelines and to compare these optimal rates with actual treatment rates. METHODS. Optimal surgery, radiotherapy, chemotherapy, and hormone therapy utilization trees were constructed based on indications from evidence-based treatment guidelines. The proportions with clinical attributes that indicated a possible benefit from a particular treatment were obtained from epidemiologic data from BreastScreen Victoria. The optimal proportions of screen-detected breast cancer patients who should receive various therapies were then calculated using TreeAge software and compared with the actual proportions obtained from the epidemiologic data. RESULTS. According to the best available evidence, the proportion of screen-detected breast cancer patients who have attributes suitable for various treatments are: breast-conserving surgery (BCS) 85%, mastectomy 15%, radiotherapy 87%, chemotherapy 34%, and hormonal therapy 68%. The actual BCS utilization rate in Victoria was similar to the optimal rate (79% vs 85%), whereas there appeared to be underuse of radiotherapy (62% vs 87%), chemotherapy (19% vs 34%), and hormonal therapy (49% vs 68%) when compared with guideline recommendations. CONCLUSIONS. This research provided optimal treatment utilization rates for screen-detected breast cancer and a comparison of best practice evidence and actual treatment. The results showed comparable rates for surgery but suggested underutilization of radiotherapy, chemotherapy, and hormone therapy. Cancer 2008. © 2008 American Cancer Society.