MammaPrint Breast Cancer Test Provides Benefits To Patients From Personalized Treatment Regimen
MammaPrint breast cancer prognosis test was successfully implemented in the diagnostic process of breast cancer patients in community hospitals in The Netherlands.
MammaPrint assigned up to one- third of the patients to different risk categories as compared to currently used risk assessment tools. In the majority of these situations, it may lead to a reduction in the use of adjuvant chemotherapy. The findings were published in the December issue of The Lancet Oncology.
In the study, breast tumors from 585 patients with lymph node-negative, invasive breast cancer, collected at 16 hospitals in The Netherlands. Fresh samples were shipped in RNAretain at ambient temperature and were subjected at Agendia Laboratories to MammaPrint gene expression analysis. Results were available for 427 patients. Based on this, patients were classified as having either a poor prognosis (high risk for distant metastasis) or good prognosis (low risk for metastasis). These results were then compared by the study coordinators to risk assessments of commonly used guidelines, including the Dutch Institute for Health Improvement (Dutch CBO) Guidelines, St. Gallen Guidelines, Nottingham Prognostic Index, and Adjuvant! Online. Many guidelines use algorithms (based on the patient's age, tumor size, and node status) to determine a patient's prognosis and determine whether or not patients should receive chemotherapy.
"More than 70 percent of patients who have node-negative breast cancer are successfully treated without chemotherapy. Identifying which patients with breast cancer will most likely require adjuvant chemotherapy is an important step in personalizing a patient's treatment regimen, and ensuring that patients aren't receiving unnecessary treatment," said Dr Laura van 't Veer, chief research officer at Agendia, who participated in the study.
According to the results in The Lancet Oncology, adjuvant chemotherapy was advised less often when the patient's prognosis was based on the DUTCH CBO Guidelines -- which are considered the most restrictive -- compared with assessments based on MammaPrint. For the other guidelines assessed,