An on-going international clinical trial, of which Tata Memorial Centre (TMC) in Parel is a partner, may change the way breast cancer is being treated in menstruating women.
The study has shown that chances of recurrence of breast cancer reduce among women less than 35 when given a treatment that suppresses ovarian function in addition to drugs.
These findings are critical to India as there are a large number of younger women with the cancer in the country. The trial found that by suppressing ovarian function and reducing the production of oestrogen in menstruating women, they could reduce the chances of relapse. Oestrogen is known to ‘feed’ cancer.
Ideally, a drug called tamoxifen is the standard treatment for menstruating women following chemotherapy in breast cancer. Post-menopausal women, who have received treatment for breast cancer, are given a class of drugs called as aromatase inhibitors (exemestane) that are known to reduce the risk of recurrence of breast cancer in them.
“By suppressing the ovarian function, we mimicked the condition similar to post-menopausal women. In one group of women, their ovarian function was suppressed and was given tamoxifen. Another received exemestane and they were followed up for five years,” said Dr Wani Parmar, breast cancer specialist, TMC, who is a part of the trial.
Among women who were given exemestane and ovarian function suppression, 91% remained free of breast cancer at the end of five years. About 88%, who received tamoxifen and ovarian function suppression, did not report recurrence and around 86%, who received only tamoxifen, reported no recurrence.
The trial, conducted among 3,000 women in 25 countries, showed most of the women remained free of breast cancer after five years. The three groups of pre- menopausal women received different forms of treatment and were in their initial stages of breast cancer.
“In this trial, women who we enrolled at TMC were menstruating even after chemotherapy. A subset of younger women (below 35), who received ovarian suppression function along with tamoxifen or exemestane benefited the most,” said Dr Parmar.
The results were presented at the annual meeting of American Society of Clinical Oncology.