MedicalResearch.com Interview with:
Judith A. Malmgren, PhD
President, HealthStat Consulting, Inc
University of Washington
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Metastatic breast cancer (MBC) has two types, de novo stage IV MBC discovered to be metastatic at initial diagnosis as advanced disease and recurrent MBC found on follow up after diagnosis and treatment for initial invasive breast cancer. Our institutional breast cancer registry tracks both de novo metastatic breast cancer and invasive breast cancer for distant metastases. With this information we were able to compare the presentation, treatment and outcomes of both types, something that is not possible in national SEER data as recurrent MBC is not tracked.
We found a remarkable improvement in 5-year survival from 28% to 55% over time among the de novo metastatic breast cancer patients. Recurrent MBC 5-year survival did not improve in the same time period (23% to 13%) although incidence of recurrent MBC fell from 18% to 7% from 1990 to 2010. Incidence of recurrent metastatic breast cancer hormone receptor and HER2 positive breast cancer declined the most, leaving a large number of triple-negative recurrent metastatic breast cancer cases in the most recent time period.
Worse metastatic breast cancer survival was associated with recurrent vs. de novo MBC, hormone receptor negative disease, older age (70+) and visceral dominant disease. HER2 positive disease was associated with better outcomes.