After breast-conserving surgery, all of the node-positive patients had adjuvant radiotherapy, as did 46% of the node-negative patients. Of the node-positive patients who had mastectomy, 69% received radiotherapy and 31% did not.
Adjuvant chemotherapy was administered to 70% of patients overall, with anthracyclines the most commonly used agent (43%). Others were the combination of anthracyclines and taxanes (32%); the combination of cyclophosphamide, methotrexate and fluorouracil (15%); and other unspecified regimens in the remainder.
Most men also received endocrine therapy (77%), with tamoxifen being the most common agent (88%).
Invasive ductal carcinoma was by far the most common diagnosis (about 85%). About half the tumors were grade 2; the rest were evenly split between grades 1 and 3.
The vast majority (1,053) were estrogen receptor positive with 93% having high expression. Progesterone receptor positivity occurred in 939 tumors, with 35% having high expression.
Most of the tumors were positive for androgen expression (1,027), again with high expression (88%). Two percent were human epidermal growth factor 2 (HER2) positive.
Not surprisingly, median overall survival was best in patients with nonmetastatic, nonnodal cancers (10.4 years). It was about 8.4 years for those with nonmetastatic, node-positive tumors, and 2.6 years for those with metastatic cancers.
Median overall mortality has significantly decreased over the years: About 70% of those diagnosed from 1990 to 1995 had died within 9 years, compared to about 40% of those diagnosed from 2006 to 2010. But breast cancer–specific mortality remained about the same, with less than 20% of patients dying by the end of follow-up.
Those with estrogen receptor–positive tumors did best, especially if they had high expression, while all of those with ER-negative tumors had died by 6 years after diagnosis. Findings were similar among those with androgen and progesterone receptor–negative tumors.
“Hormone receptor status had a very good prognostic value, with positive, highly expressed tumors having much better outcomes,” Dr. Cardoso said, adding that tumors in this initial phase of the study are still being examined.
She had no financial disclosures.
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