Cancer researchers at Massachusetts General Hospital, pictured, reported Wednesday that a new study indicates that pre-surgery endocrine therapy is just as good as traditional chemotherapy, minus the potentially-harmful side effects. The study also examined variations of endocrine therapy that inhibit hormone signaling or stymie potentially cancer-fueling hormone production altogether. File Photo/Matthew Healey/UPI | License Photo
BOSTON, Nov. 9 (UPI) -- Endocrine therapy for women fighting breast cancer might be just as helpful as traditional chemotherapy before tumor removal surgery, according to researchers at the Massachusetts General Hospital Cancer Center.
A new study conducted at the center found that pre-surgery endocrine therapy -- treatment that blocks the production of potentially cancer-fueling hormones -- for women with localized, estrogen-receptor-positive breast cancer produces virtually the same results as presurgical chemotherapy, but with fewer side effects.
Both processes are designed to reduce the size of breast cancer tumors before surgeons operate to remove them.
"Tumors are generally highly receptive to endocrine therapy ... but while endocrine therapy is the most important component of [secondary] or postsurgical therapy, use of [pre-surgery] endocrine therapy has been low in the U.S.," Dr. Aditya Bardia, the study's lead author and assistant professor at Harvard Medical School, said. "Since the chemotherapy more commonly used in this situation might not be the best option for patients with these tumors, we conducted a comprehensive, systematic review and meta-analysis to evaluate rigorously the existing scientific evidence."
The researchers said they undertook the task of testing endocrine therapy before surgery because such treatment has not previously been sufficiently explored.
The study also examined how effective different variations of pre-surgery, or neoadjuvant, endocrine therapy were -- such as drugs that block signaling at the estrogen receptor, and aromatase inhibitors that stymie estrogen production altogether. Studies have shown that in some cases hormones like estrogen can facilitate cancer growth.
The study indicated that aromatase inhibitors work better.
"Overall, treatment outcomes were similar in patients treated with neoadjuvant chemotherapy and those receiving neoadjuvant endocrine therapy, but patients receiving chemotherapy had significantly greater toxic side effects," researchers said in a statement Wednesday. "Comparing the results of different endocrine therapies revealed that neoadjuvant treatment with [estrogen] inhibitors was significantly more effective than treatment with [relevant] drugs."
"There's no reason our findings cannot be applied to treatment right now," Dr. Laura Spring, the study's lead author and senior oncology fellow at the MGH Cancer Center, said. "With the spurt in development of new targeted therapies ... more research is needed to look at combining endocrine therapy with those drugs for neoadjuvant treatment."
With an annual research budget of $800 million, Massachusetts General is one of the leading research hospitals in the United States and is the main teaching hospital for Harvard University Medical School.
The study, which appears in the current edition of JAMA Oncology, was announced the same day as European researchers reported that intense versions of chemotherapy offered no extra benefit over standard chemo.