Even the lowest-risk women who originally had the small tumors have not spread to the lymph nodes or other parts of the body still had 10 percent chances of the cancer coming back during the study.
Many women who after initial treatment of breast cancer with five years of hormone therapy to keep tumors at bay, can still new malignancies to two decades after their diagnosis, a study suggests.
The researchers examined the data from 88 clinical trials in which 62,923 women with estrogen receptor (ER)-positive tumors. After the treatment, ER-positive tumors with chemotherapy, radiation or surgery, the women, usually five years of follow-up of therapy with daily hormone-based pills – either tamoxifen or aromatase inhibitors. The goal of adjuvant therapy is to destroy residual cancer cells not killed by the first treatment.
All women were free of cancer when they completed five years of adjuvant hormonal-based therapy.
National Breast Cancer Awareness Month: Important terms you should know
In the next 15 years, but cancer returned for 41 percent of the high-risk women in the study who initially had the largest tumors that had spread most of the outside of the chest, the study found.
FDA APPROVES NERVE-STIMULATOR FOR WITHDRAWAL SYMPTOMS
Even the lowest-risk women who originally had the small tumors have not spread to the lymph nodes or other parts of the body still had 10 percent chances of the cancer coming back during the study, researchers report online November 13 in the New England Journal of Medicine.
“We know that adjuvant (hormonal) therapy for 5 years substantially reduces the risk of recurrence and mortality,” said senior study author Dr Daniel Hayes of the University of Michigan Comprehensive Cancer Center in Ann Arbor.
“We now have the proof that extending adjuvant (hormonal) therapy for more than five years will remain the control and reduction of recurrence and mortality rates,” Hayes said by e-mail.
Doctors have long known that five years of tamoxifen reduces recurrence by approximately half during treatment, and by almost a third in the next five years. Aromatase inhibitors, which work only in the post-menopausal women, even more effective than tamoxifen at reducing recurrence and death from breast cancer.
Some recent research suggests an additional five years of hormone-based therapy is even more effective, but the side effects make some women hesitate to go further. Life-threatening side effects are rare, but women who have this hormones can symptoms of menopause such as hot flashes and vaginal dryness.
The data suggest that women with ER-positive breast cancer should at least consider the continuation of adjuvant therapy after five years, the authors conclude.
“Breast cancer cells can travel from the primary tumor in the lymph nodes and circulate through the body to detect with current screening (methods) and over time, these circulating cancer cells may attach to other organs in the body and this is generally when there is a detectable cancer recurrence,” said Albert Farias, a cancer researcher at the Keck School of Medicine of the University of Southern California in Los Angeles who is not involved in the study.
“A way that adjuvant treatment of breast cancer works is to kill and/or stop of the undetectable cancer cells from growing and dividing,” Farias said by e-mail.
DOCTORS CLAIM THAT BABIES IN 2015 THE DEATH WAS CAUSED BY A MARIJUANA OVERDOSE
Although the study suggests that some women have more risk of recurrence based on their original tumor characteristics, it can still be difficult to predict, and women should continue to be vigilant, said Dr. Sharon Giordano of the University of Texas MD Anderson Cancer Center in Houston.
“Breast cancer can be dormant for many years, so that women can have no apparent illness, but can still return years later when the tumour becomes active again,” Giordano said by e-mail. “We do not know why some cancers become active again after years of dormancy.”
Women should have regular check-ups and breast cancer screening, as well as annual mammography, said Dr. Alana Large, a researcher at the University of Illinois-Chicago who not involved in the study.
“If a woman has a high risk of breast cancer, such as a lady with a gene mutation, can they both mammography and breast Mri,” Large added via e-mail. “In addition, women should maintain a healthy weight, exercise, stop smoking and limiting the consumption of alcohol to reduce their risk of recurrence.”