Stress drugs halt spread of breast cancer
High levels of stress are associated with breast cancer, researchers at Trinity College Dublin have found.
And women who take drugs to manage stress hormones have a much lower risk of dying from the disease, Irish researchers have learned.
The groundbreaking discovery was made by scientists at Trinity College Dublin (TCD), who found that the inexpensive drugs could significantly halt the spread of the disease.
The research published today in the Journal of Clinical Oncology by Dr Ian Barron, of Trinity, looked at women diagnosed with breast cancer in Ireland over a number of years up to 2007.
"For patients with cancer, higher levels of stress are associated with more frequent disease recurrence, faster disease progression and higher rates of death from cancer," Dr Barron said.
His research found that the likelihood of women being diagnosed with invasive or metastatic breast cancer was less if they were taking the drugs in the year prior to their diagnosis.
"Because the majority of all cancer deaths are due to the growth of tumour metastases, this research could have significant implications for clinical practice," Dr Barron said.
The researchers used data from the National Cancer Registry and the HSE Primary Care Reimbursement Services.
They found that those taking drugs that blocked a particular hormone-related stress pathway had a much lower risk of dying from their cancer.
Dr Barron said it was the first study in humans to show that blocking the stress response greatly reduces the risk of cancer spreading or metastasising.
The research showed women continuing to take the drug after their diagnosis were considerably less likely to die from the disease in the five years following diagnosis.
Previous research elsewhere had found that women with advanced breast cancer who have abnormal daytime levels of cortisol, a hormone released in response to stress, were significantly more likely to die sooner than patients with normal levels of the hormone.
It was discovered more than a decade ago that women with abnormal cortisol levels had fewer immune-system 'natural killer' cells, and this reduced immunity was associated with higher mortality.