Men with prostate cancer have a greater risk of potentially life-threatening blood clots, a new study has found.
And men undergoing hormone therapy for their condition have the highest risk.
Although it’s well known that having cancer increases the risk of developing blood clots, little is known about the risk associated with prostate cancer alone.
Researchers from King’s College London and international partners analysed data from over 75,000 Swedish men with prostate cancer receiving different types of treatment between 1997 and 2007. During this time 1881 men developed blood clots.
Overall, the findings, published in Lancet Oncology, showed that men with prostate cancer were significantly more likely to develop blood clots in the legs and lungs than men without prostate cancer.
In addition, men undergoing hormone therapy therapy were two-and-a-half times more likely to have a blood clot in the leg, and nearly twice as likely to develop one in the lungs compared with the general population.
The risk was especially high for younger men – less than 65 years old – and for men with advanced prostate cancer.
The researchers suggest the increased risk of blood clots is likely to be due to a combination of factors such as the cancer itself, age and the type of treatment for the condition.
Dr Helen Rippon, Head of Research Management at The Prostate Cancer Charity said it was not surprising that the researchers had found a greater risk of blood clots in men with prostate cancer. She also said: “It is important to remember that the researchers have simply discovered a relationship between hormone therapy and blood clots.
“This does not prove that one causes the other and there may be many other factors at work that could explain this relationship.
“Men on hormone therapy should not be unduly worried as a result of this research. Hormone therapy has clear, proven clinical benefits and can keep advanced prostate cancer at bay for months or even years.
“The results of the study certainly do not suggest that hormone therapy should be stopped or not offered to men who would normally be expected to benefit from it in treating their cancer.
“Doctors always make treatment recommendations taking into account each man’s own medical history, and make judgements about the possible risks and benefits of this treatment on an individual basis.
“We urge any man on hormone therapy who is concerned that he might be at greater risk of blood clots to speak to his specialist before making any decisions about whether to continue with the treatment,” she added.