Sexual activity, disease transmission, and prostate cancer: let’s get the facts straight


Editorial note: The content in this post is specific and may be offensive to some readers. Unfortunately, biology being what it is, clarity of expression is sometimes essential to accuracy of communication.

The other day, a female correspondent left a question on this site asking, “Is there any risk in the ejaculate for the partner of a man with prostate cancer?”

We responded by stating clearly that, “As far as anyone is aware there is absolutely no risk of any transmittable disease related to prostate cancer, through male ejaculate or otherwise. Any man who has been effectively treated from prostate cancer will, in any case, have ‘dry’ orgasms with no ejaculate because his prostate tissue is dead.”

However, the corresponent apparently heard a somewhat different message from her physician when she asked the same question. The doctor appears to have indicated that, while there is no risk to a female partner in the male ejaculate of men with as yet untreated prostate cancer, “the situation would be different for a male partner.”

We have no wish to put words in anyone’s mouth; we don’t know exactly what the doctor said to this correspondent; and this may be a simple case of miscommunication. However, we would like to be extremely clear about this issue. We are aware of no reason whatsoever to believe that male-male intercourse is associated with any risk for transmission of prostate cancer. If this was the case, then there would almost inevitably be a higher incidence of prostate cancer among gay men in the USA than among straight men, and that is certainly not the situation.

Having said that, there are, of course, specific risks related to disease transmission associated with all forms of intercourse. These are most commonly related to transmission of infectious diseases. Furthermore, certain types of cancer (e.g., cervical cancer) are known to be associated with viral infections (HPV infection in the case of cervical cancer), and this is why vaccination of young women against certain strains of the HPV virus was recently approved in the USA and in Europe. The most recent data actually suggests that vaccination of men may also help to prevent the spread of HPV and therefore the incidcence of cervical cancer.

It is also the case that vaginal intercourse is associated with differing risks than anal intercourse because of the biological properties of the differing organs and tissues involved (regardless of whether two males or a male and a female are involved in the latter activity).

What is of great concern to us is to ensure that the potential for misinformation here is ruled out. We know of no data to suggest that there is any chance for transmission of prostate cancer from a male to another male as a consequence of sexual activity. Furthermore, to date, there is no evidence that risk for prostate cancer has ever been associated with transmission of any other form of disease as a consequence of intercourse.

There are some data that suggest the possibility of an association between prostate cancer and the XMRV retrovirus (see a recent presentation by Klein). XMRV can be identified in expressed prostatic secretions in some 10-15 percent of men with prostate cancer. However, as yet there are no data that substantiate either the sexual transmission of the XMRV virus or a cause and effect relationship between the presence of the virus and the onset of prostate cancer.

8 Responses

  1. Mike,

    I agree with your statement but I wonder if the incidence rate comparison between gay men and straight men has been studied? Just saw an email recently saying that research on prostate cancer incidence issues in gay men has not been adequately studied. If the doctor said what she thinks he said, sound like the statements I have heard that abortion raises the rates of breast cancer.

  2. Ever since the AIDS crisis there have been ongoing studies to monitor comparative risks related to disease in gay versus straight men (albeit not widely publicized for some fairly obvious reasons). I am as sure as I can be that if prostate cancer had a particularly high incidence and prevalence in gay men, they would know about it by now, particularly in centers with a large, “out” gay population like San Francisco that has a sophisticated system specifically focused on health issues in the gay community and two major prostate cancer centers of excellence.

  3. Mike’s assumption regarding our knowlege of incidence discrepencies in gay versus straight population is not correct. There are no large scale survalence studies around prostate cancer that have asked for the sexual and gender identity of the respondents. There are several LGBT focused nonprofits, including Malecare, Out With Cancer and The National Coalition for LGBT Health, who are currently identifying tested survey instruments around this issue. But for now, the clear answer is, we don’t know if gay or bisexual men, or transgender women, are more or less vulnerable to prostate cancer.

  4. Dear Darryl: With the greatest respect, I neither said nor suggested that there had been large-scale prostate cancer-specific surveillance studies related to sexual proclivities.

  5. From a recent posting on the web site of the National LGBT Cancer Project:

    Researchers analyzed data on 19,410 men who participated in a California-statewide health survey (Heslin et al., Medical Care, December 2008). Researchers looked at the use of prostate-specific antigen testing among gay/bisexual and heterosexual men and found no significant differences. However, the percentage of black gay/bisexual men who had undergone the test was 15% to 28% lower than gay/bisexual whites and 12% to 14% lower than heterosexual black men. The finding is significant because black men are more likely to be diagnosed with prostate cancer than any other racial or ethnic group (University of California-Los Angeles Center for Health Policy Research newsletter, December 2008). This study suggests that further research be conducted to examine racial and ethnic differences in cancer testing (Medical Care, December 2008).

  6. Good find Darryl. Thanks! Can you get a PDF of the actual Heslin et al. article? I would love to know exactly what percentage of the patients were (a) over 50 and (b) provided the data on which these results are based. It certainly wasn’t all 19,410 men in the original health survey, and I would like to be sure I understand the level of statistical significance of these data.

    And please be assured that I absolutely agree that we need to be really sure about any difference in risk level for prostate cancer among those with different sexual proclivities (although human nature may make it difficult to know this with high levels of accuracy).

  7. I have the same question as the woman above. Can prostate cancer cells be transmitted semen ejaculated during intercourse? My husband and I are in our 70s, still sexually active, and he has just been diagnosed with prostate cancer. In my computer research, all of the doctors respond with, “As far as I know, it cannot be transmitted”. No examples of tests or trials is ever given in those answers.

    Has anyone actually tested semen ejaculated by a man with prostate cancer to see if cancer cells are in the semen, and can that semen actually cause cancer if repeatedly implanted into a healthy vagina?

    Can anyone answer this question via tests/trials?

  8. Dear Lynn:

    First, it is an absolute certainty that a man with untreated prostate cancer can and does ejaculate at least some prostate cancer cells in his semen some of the time. This was demonstrated several years ago (by Gardiner et al.).

    However, the fact that prostate cancer cells are ejaculated into the vagina does not imply that these cells can survive in that environment. The female vagina is not an environment in which it is easy for foreign cells to survive, for starters. Cancer cells are not “infectious.” They require a very specific physiological environment, including relatively high levels of testosterone, to survive and grow. The vast majority of women do not have high levels of testosterone. Every year, for thousands of years, men with prostate cancer in their prostates (and men with prostate cancer that has spread beyond their prostates) have been ejaculating prostate cancer cells. During that entire time period, I am aware of absolutely no documented case of prostate cancer in a female (not a single one). If there was even one chance in 100,000 that this could occur, we would have been seeing at least a few cases of prostate cancer in women in America every year — and yet, over the past 30 years, during which time there has been a massive increase in research into prostate cancer (and a massive increase in the number of men who get diagnosed each year), there is no documentation of a single case.

    Having said that, there is a relatively simple method to resolve your concern … ask your husband to use a condom, although I have no reason to believe that this is necessary.

    It is impossible to “prove a negative” like this … All that I or anyone can tell you is that there is no evidence at all to support your hypothesis.

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