Tel Aviv University (TAU) researchers have carried out a comprehensive study on what brings about metastases in cancer patients, the university announced on Wednesday.Their findings, published in the scientific journal Nature, claim that the brief time period before and after tumor removal surgery is vital for the prevention of metastases. TAU noted further that anti-mestatic treatments available today normally ignore the "critical period around the surgery," which tends to leave medical staff stuck facing a progressive and resistant metastatic process in the months or years to follow. To preemptively combat this, the researchers explain that patients preparing for or recovering from such surgery should make the effort to undergo immunotherapeutic treatment in concert with treatments focused on reducing inflammation in order to stave off post-surgery metastases – as well as therapies geared towards reducing physical and psychological stress.One such immunotherapeutic treatment patients should consider is one where physicians inject substances containing similar receptors to viruses and bacteria into the body. The immune system would then recognize the substance as a threat and activate itself, in turn preventing a metastatic disease.With regard to physical and psychological stress, which normally occurs during surgery, sets of hormones called prostaglandin and catecholamine are produced in greater amounts, suppressing the immune system cells' activity, and inadvertently speeding up metastasis. Additionally, these hormones give residual tumor cells that are still present in the body after surgery the ability to develop into life threatening metastases, making these cells more aggressive and metastatic in the process.This breakthrough, however, contradicts the medical community's present assumption that cancer patients, as with chemotherapy and radiation therapy, should not be given immunotherapeutic treatment in the month previous to or following tumor removal surgery."Surgery for the removal of the primary tumor is a mainstay in cancer treatment, however the risk of developing metastases after surgery is estimated at 10% among breast cancer patients, at 20%-40% among colorectal cancer patients, and at 80% among pancreas cancer patients," said Prof. Shamgar Ben-Eliyahu from the School of Psychological Sciences and the Sagol School of Neuroscience at Tel Aviv University.“Medical and immunotherapeutic intervention to reduce psychological and physiological stress, and activate the immune system in the critical period before and after the surgery, can prevent development of metastases, which will be discovered months or years later,” concluded Ben-Eliyahu.