SOURCE:
The research, conducted by Marleen Kok, MD, PhD, Department of Medical Oncology, the Netherlands Cancer Institute, Amsterdam, and colleagues, was published online in JAMA Oncology.
LIMITATIONS:
The authors noted that the study was limited by its observational nature. The patients were drawn from a larger cohort, about half of whom received adjuvant chemotherapy, and the patients who did not receive chemotherapy may have had favorable tumor characteristics. There were also no data on BRCA1 or BRCA2 germline mutation status and recurrences and/or distant metastases. The database did not include data on patient ethnicity because most Dutch patients were White.
DISCLOSURES:
Research at the Netherlands Cancer Institute was supported by institutional grants from the Dutch Cancer Society and the Dutch Ministry of Health, Welfare and Sport. Dr. Kok declared financial relationships with several organizations including Gilead and Domain Therapeutics, as well as institutional grants from AstraZeneca, BMS, and Roche. Other authors also declared numerous financial relationships for themselves and their institutions with pharmaceutical companies.
A version of this article first appeared on Medscape.com.