This is bad news for cancer survivors

Mar 22, 2010 10:34 GMT  ·  By

Over the past few years, more and more people have survived their cancer diagnostics, which finally gave researchers an opportunity to investigate the long term effects of treatment methods such as radiotherapy. Alongside chemotherapy, this is one of the most used medical approaches to treating the terrible condition, but researchers say that it can produce some very intense side-effects. In studies on cancer survivors, researchers at the Karolinska Institutet, in Sweden, determined that the therapy produced an elevated risk of lasting cardiovascular disease later on in life, AlphaGalileo reports.

The KI investigators also provide a possible answer to this enigma, but say that more work is needed to validate their preliminary results. They argue that the reason for why vascular health deteriorates may lie with the changes in gene expression patterns that post-radiotherapy inflammation generates. The team underlines, however, that the correlation between radiotherapy and cardiovascular diseases only hold when the treatment is applied to specific parts of the body.

For example, they determined that the risk was greater for patients who undergo left-side breast cancer treatment. These women will later find themselves at an increased risk of myocardial infarction. At the same time, people who treated their head and neck or brain tumors may find themselves at an increased risk of stroke, the team says. But what throws experts off-balance even now is that fact that they still can't pinpoint the biological causes for these side-effects. The negative consequences only appear to develop a number of years after radiotherapy ended, which suggests a very complex mechanism.

“Studies have been hampered by the fact that the disease process is so slow. Cell studies and animal studies are best suited to the more immediate effects, and studies on human subjects have been ruled out for ethical reasons,” says KI expert, Martin Halle. For the new work, the researchers compared arterial samples taken from either irradiated patients, or from the grafts that are generally used to patch up places from which a tumor was extracted. They learned that, even years later, chronic inflammation in gene expression persisted, hinting at a link. ”Hopefully, these findings will one day help medicine to mitigate the side effects by administering radiotherapy in combination with an anti-inflammatory treatment,” Halle says.