They found that the expression of progesterone receptor was one of the most discriminatory molecules. "Addition of quantitative scoring of the progesterone receptor into the current pathology-based Luminal A definition appears to better identify the subgroup of patients that have an outstanding survival when treated with endocrine therapy alone, and therefore do not need systemic chemotherapy," Dr Prat said. "This subpopulation of patients is likely to represent around 30% of the patients with low-risk pathology-defined Luminal A tumors."
"Current pathology-based definitions of the Luminal A and Luminal B subtypes are valuable, but can be improved for the management of hormonal receptor-positive breast cancer," the researcher concluded. "We believe that we have an improvement based upon the progesterone receptor, and given that progesterone receptor is widely used, our improvement could be widely and quickly adopted, if further validated."
According to Dr Di Leo, Hospital of Prato, Italy, former IMPAKT Chair, this is an important study with practical implications, because it tells us that the evaluation of the progesterone receptor along with the evaluation of other biomarkers, such as the estrogen receptor, proliferation markers and c-erbB2, may be relevant to better define the biological profile of the tumor. "This is a critical step towards a personalized medicine approach in breast cancer. It will be important to test the progesterone receptors according to a standardized approach across the pathology departments. One potential concern, in fact, could be the use of different techniques for the progesterone receptors eval
|Contact: Vanessa Pavinato|
European Society for Medical Oncology