This story originally ran on July 16.
Diagnostics firm Clarient announced this week the publication of a 1,540-patient study investigating the use of its protein biomarker breast cancer diagnostic Mammostrat, which the company said would become commercially available in the fourth quarter of this year.
The study, which was led by University of Edinburgh molecular pathology professor John Bartlett and will be published in an upcoming edition of Breast Cancer Research, reinforced data from four previous studies demonstrating Mammostrat's use as a prognostic tool for node-negative, estrogen-receptor positive, tamoxifen-treated breast cancer and suggested for the first time that the test might also be useful in node-positive, estrogen-receptor negative cohorts, as well, the company said in a statement.
Mammostrat is an immunohistochemical assay that measures the presence of five proteins – SLC7A5, HTF9C, P53, NDRG1, and CEACAM5 – in tumor cells and applies a diagnostic algorithm to classify patients as having a high, moderate, or low risk of recurrence after surgery and treatment with tamoxifen. This classification helps doctors and patients decide whether additional aggressive chemotherapy is needed as part of treatment.
According to Clarient vice chairman and CEO Ron Andrews, the test has now been validated for use in stratifying node-negative, estrogen-receptor positive, tamoxifen-treated breast cancer patients in studies involving over 3,000 women.
Mammostrat does not incorporate conventional clinical stratifiers and biomarkers such as hormone receptor status, HER2 status, or measures of proliferation. Use of the test along with these conventional approaches "has the potential to give a full accounting of the clinically relevant biological diversity of breast cancer in considering therapy options," the study said, adding that research investigating such combinations is currently underway.
The paper also noted that validation of the assay will require future studies demonstrating its reproducibility across multiple laboratories.