It was published in theJournal of Clinical Oncology.
Endocrine therapy uses drugs that suppress estrogen from the ovaries that fuels the cancer cells.
These types of drugs includetamoxifen, goserelin, and other hormonal therapies.
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About 80% of breast cancers are sensitive to estrogen.
The combination of goserelin and tamoxifen was no better than either drug alone.
Esserman is a professor of surgery and radiology at the University of California, San Francisco.
For women with molecularly low-risk disease, tamoxifen was better than goserelin.
People with molecularly high-risk tumors have a higher risk of cancer recurrence in the first five years after treatment.
Low-risk tumors are more likely to have a risk at a later time after treatment.
Sweden is unique in its ability to track patients for long periods of time, she said.
This is unfortunately rare, but here, the investment the Swedes have benefited us all.
But many women struggle with side effects of hormone therapy and want to cut the treatment short.
Side effects of tamoxifen include menopause-like symptoms, nausea, fatigue, depression, and headache.
Some patients struggle so much with the side effects of therapy that they need to stop.
2015;6(3):231-239. doi:10.4331/wjbc.v6.i3.231
