Dr. O'Shaughnessy on Breast Cancer Biomarkers

Joyce A. O'Shaughnessy, MD, Breast Cancer Research, Baylor Sammons Cancer Center in Dallas, TX, begins by mentioning that the HER2 marker is already a focused part of breast cancer. She believes that some biomarker selection will become necessary and that it is no longer feasible to approach the adjuvant setting with a mixed population of patients with triple-negative breast cancer and indolent ER-positive breast cancer.

O'Shaughnessy believes it is not feasible to find a selection marker for everything, but she believes some selection needs to take place. There is a great deal of systems biology that comes into play when dealing with breast cancer. Because of its complex nature it may not be possible to know every operative pathway and microenvironment, at this time, but a basic understanding of the biology is needed

Future selection of patients may also be based not only on a positive outcome but also a negative. If you know a patient will not respond positively because they posses a certain marker you may exclude them from studies. Using biomarkers in this way can be just as useful as a positive outcome.

There is currently a great deal of effort being focused on discovering very narrow subsets of patients, and this will produce some success, but in the long run O'Shaughnessy believes broader based biological subsets will be more successful.