THE "NEW" PROSTATE CANCER INFOLINK

And in a report in the Los Angeles Times “Booster Shots” blog, “Men who are infected with the sexually transmitted bacterium Trichomonas vaginalis have a slightly increased risk of developing prostate cancer and double the normal risk of developing the aggressive form of the disease that spreads throughout the body.”

Taken in combination with the XMRV virus story from earlier in the week, this study adds to the idea that some form of inflammatory process, caused by an infection, could either lead to the development of prostate tumors or could accelerate their growth.

By analyzing data from 673 patients with prostate cancer in the Physicians’ Health Study and comparing the data from these patients with similar data from 673 individually matched subjects in  the same study who did not have prostate cancer, Stark et al. have shown that the presence of antibodies against Trichomonas vaginalis, a common, sexually transmitted, infectious bacterium, was positively associated with subsequent incidence of prostate cancer. They were also able to confirm this in an independent population.

The actual results of this study are as follows:

• It confirmed that there was an association between prior infection with  T. vaginalis and overall prostate cancer risk.
• It showed that the size of that association was small but similar to that shown in prior reports.
• Prior T. vaginalis infection significantly increased the risk for extraprostatic prostate cancer and for cancer that would ultimately progress to bony metastases or prostate cancer–specific death.

According to the paper, 25 percent of the prostate cancer patients and 21 percent of the non-prostate cancer controls, respectively, were seropositive for T. vaginalis, so the association between a prior infection with T. vaginalis and overall risk for prostate cancer was very small. The important issue here is that in patients diagnosed with prostate cancer, a history of T. vaginalis infection appears to predispose patients to greater risk of progressive disease.

Since it is not difficult to identify antibodies to T. vaginalis in blood, the authors concluded that if this association between a positive result for T. vaginalis infection and risk for progressive prostate cancer can be confirmed, then so-called “seropositivity” for T. vaginalis could serve as a prognostic marker for adverse outcomes in patients diagnosed with  prostate cancer or, potentially, as a way to better identify men who might benefit from chemoprevention using drugs like finasteride and dutasteride. In other words, if you are already at risk, and you are also seropositive for T. vaginalis, then your chances of benefiting from chemoprevention go up significantly.

Filed under: Diagnosis, Living with Prostate Cancer, Management, Risk, Uncategorized Tagged: | risk, serum, T. vaginalis