"Even though these women remained free of recurrence in the first five years, the risk of having their cancer recur elsewhere (for example in the bone, liver or lung) from years five to 20 remained constant", said Daniel F Hayes, Professor at the University of MI in the US.
The study, involving nearly 63,000 women from 88 clinical trials, has found that the absolute cumulative risk for metastatic or distant recurrence among women with this most common form of breast cancer ranges from 10% to 41% over that time span, depending on various disease characteristics.
Professor Arnie Purushotham, Cancer Research UK's senior clinical adviser, said: This research shows that stopping hormone treatment at five years leaves women with an ongoing risk of breast cancer coming back in the distant future.
This is a type fuelled by the hormone oestrogen which can stimulate cancer cells to grow and divide.
Colts DB Vontae Davis released from team
The move comes one day after multiple outlets reported that Davis would have season-ending groin surgery. Davis has been listed on the injury report just twice since Week 4, both days listed as "rest days".
Patients can appear cancer-free but the disease may return many years later with tumours spreading through the body, according to the analysis of data from 88 clinical trials. He said that the risk remained the same each year and was still "strongly related to the size of the original cancer and whether it had spread to any lymph nodes".
Dr Hongchao Pan, a lead researcher on the study from the University of Oxford, said it was "remarkable" that breast cancer can remain dormant for so long and then spread many years later.
Scientists analysed the progress of 63,000 women for 20 years.
It's important to point out that since this research began, new drugs are being used to treat breast cancer, and these work in a different way to tamoxifen.
Treatments for breast cancer have improved in recent years, so the estimated risks of recurrence may be on the high side, said co-lead author Richard Gray, of the University of Oxford.
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They also inaugurated railway bridges over rivers Meghna and Titas on the main Chittagong to Dhaka trunk rail line in Bangladesh. The fully air-conditioned weekly passenger train service "Bandhan Express" will run every Thursday from both Kolkata and Khulna.
He said: "It's vital that work continues to better predict which cancers might return". Although side effects are rarely life-threatening, they can substantially impact a woman's quality of life.
These include menopausal symptoms, osteporosis, joint pain and carpal tunnel syndrome.
As the authors of the current study write, "D$3 ecisions about extending adjuvant endocrine therapy after 5 years without any recurrence need to balance additional benefits against additional side effects".
"Even though these women remained free of recurrence in the first 5 years, the risk of having their cancer recur elsewhere (for example in the bone, liver, or lung) from years 5 to 20 remained constant".
Ultimately, the decision is up to a woman and her doctor, said Hayes.
Chrome will soon block annoying website redirects
Chrome 65 will begin detecting this behavior and again will trigger an infobar to prevent the main tab from being redirected. Google admits these sites are effectively circumventing Chrome's pop-up blocker by exploiting how redirects work.