The “androgen deprivation therapy” (ADT), a wide spread treatment used for prostate cancer, might increase the risk of colon cancer, suggests new study.
The treatment holds back the production of testosterone and it is widely used despite growing evidence that it brings severe risks, such as diabetes or obesity, known to be themselves risk factors for another type of cancer – colon cancer.
Researches done on animals hint that colon cancer could be prevented through male hormone therapy, as it blocks signals that cancer cells need in order to grow. In reverse, male hormone deprivation is likely to facilitate the apparition of cancer.
The researchers have looked at the incidence of colon cancer in more than 100,000 men diagnosed with prostate cancer from 1993 to 2002 and treated with ADT, either in the form of surgery or drugs. Until 2004 when observations were concluded, they found that men who received hormone-blocking treatments had 30-40 percent higher risk of colon cancer, which was increased by the duration of the therapy.
The study, however, was observational, aiming to find a link between the treatment and colon cancer. The researchers said that the overall risk of colon cancer in men was still small, as only 2.2 percent of the men receiving ADT drugs and 3.2 percent of those who have undergone surgery developed the disease, compared to 1.8 percent in the group that received no hormone-blocking therapy.
The authors of the study say that men should consider the risk before undergoing any hormone-blocking therapy, but that, given the low risk, if the therapy might bring benefits that outweigh it, they should not stay away from ADT.
Several hormone-blocking therapies have been pointed out by the Food and Drug Administration in the US as carrying risks of heart conditions and diabetes and the agency ruled that they should have warning labels for these risks.
