Is Prostate Cancer Really a Sexually Transmitted Disease?
You probably can’t get away from the headlines this week claiming that prostate cancer is a sexually transmitted disease. Here’s the truth behind those claims.
The headlines are the result of a paper published by researchers from the University of California which found that an infection transmitted through unprotected sex appears to aid prostate cancer growth. HPV infection is a well-known cause for cervical cancer in women, but linking an infection to prostate cancer is relatively new territory, so what is going on here?
The infection in question is the non-viral Trichomoniasis, which is caused by a very small parasite. According to the CDC, it is the most common curable sexually transmitted infection in the world today. Men and women may not even know they have the parasite, and in about 50% of cases will show no symptoms.
That said, for women the infection can sometimes cause soreness and itching as well as vaginal discharge. For men who display symptoms, common problems include pain during urinating and a white discharge. In addition, the head of the penis and the prostate gland can become infected — and this is where prostate cancer may come into play.
Researchers in this latest study found the parasite that causes the infection generates a protein that, under lab tests, caused inflammation and increased benign and cancerous prostate cells. This isn’t the only study to show a possible link, either.
Research conducted by the Harvard School of Public Health in 2009 showed that around a quarter of men who had prostate cancer in their test group also had trichomoniasis. In addition, they were more likely to have advanced tumors, possibly indicating that trichomoniasis prompts more aggressive prostate cancer. Research in 2006 pointed to a similar result, but so far only a handful of studies have shown this link.
Does that mean that prostate cancer is sexually transmitted then? Of course not, and it’s very misleading to quote the scientists in the California study as saying that because, bluntly, they haven’t. What they have said is that more research is needed in this area because there is still no concrete evidence to show what might cause prostate cancers, and trichomoniasis infection could be a good sign-post for further exploration. Currently, there is no firm evidence for a link and even if there was, implying that prostate cancer is sexually transmitted is dubious to begin with — it would be the infection, not the cancer, that would cross during unprotected sexual contact.
Prostate cancer isn’t among the most fatal cancers and, if caught early, is highly treatable. Around 233,000 men are diagnosed every year in the United States. It’s estimated that in 2014 about 29,480 men will die due to developing prostate cancer. While prostate cancer can technically develop anytime during our later adult lives, it tends to affect those over 70.
Our best research suggests there is a genetic component to developing prostate cancer. What’s more, men who have relatives that have had breast cancer also seem at greater risk of developing prostate cancer, especially if those relatives were diagnosed under the age of 60. Scientists have already uncovered a number of genes that they believe predict a man’s risk of developing the disease, and there is also a link between prostate cancer and colon cancer. Of course, the usual lifestyle factors probably play their part, especially in the rising number of prostate cancer diagnoses.
If research does ultimately show that Trichomoniasis can trigger prostate cancer, scientists might then develop a vaccination campaign similar to that which is currently recommended for HPV/cervical cancer. They will also be able to screen more effectively for the infection and the likelihood of developing prostate cancer.
So, this new study is important as a guide for future research, but so is not believing the headlines which have hyped these findings and made them out to be something they are not.
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