Endocrine therapy may cause many bothersome side effects, often affecting a patients compliance. Dr Naughton suggests BCI as a tool to objectively help patients understand their likelihood of benefit and help encourage them to continue therapy, if appropriate.
Breast Cancer Index (BCI) validation studies included both women treated with aromatase inhibitors (AI) and women treated with tamoxifen (Tam). The three validation studies included patients treated with Tam only (Stockholm), either anastrozole or Tam (ATAC), and Tam with a transition to letrozole (MA.17).
Dr. Naughton recognizes the difference between risk of recurrence and likelihood of benefit from extended endocrine therapy, noting the two do not always correlate, as they can be based on separate biological mechanisms. A patient at high risk of recurrence does not inherently imply that patient will respond to a particular therapy.
Previously, risk reduction from treatment with endocrine therapy has been represented as a general percentage for all patients treated. Knowing that in reality each patient responds differently, Dr. Naughton stresses the importance of tailoring treatment decisions based on the individual patient situation.
Dr. Naughton discusses the bothersome side effects and serious safety risks associated with endocrine therapy. He emphasizes the need to weigh patient benefit versus the impact on quality of life due to these side effects and safety risks when considering patient treatment options.
Dr Stephen C. Malamud and Dr Susan K. Boolbol discuss the importance of using a clinically validated test such as the Breast Cancer Index (BCI) and its impact on patient confidence in their treatment plan.
Dr Stephen C. Malamud and Dr Susan K. Boolbol consider the clinical utility of the Breast Cancer Index (BCI) as a test that separates those patients who are more likely to benefit from those who are unlikely to benefit from extended endocrine therapy.