HPV vaccine shows efficacy in preventing anal cancer

A study in Clinical Infectious Diseases shows evidence that Gardasil has efficacy in the prevention of anal cancer in a population of HIV-negative gay men. To repeat a theme I've put forward many times in this blog, strains of HPV have been linked by varying degrees of evidence to nearly one dozen types of cancer, and for those we've been able to get a handle on, when we look closely, we see HPV vaccines demonstrating efficacy at reducing those forms of cancers. It is not difficult to imagine that this trend might continue as we carefully examine the rest of those types of cancer.

CDC recommends vaccinating boys

The CDC today recommended vaccinating boys starting at the age of 11.

I'm glad that I'm able to say "I told you so.", not just because I love being right (I do), but because this is a reflection of the fact that we have a fucking vaccine that prevents a fair number of types of cancers in both men and women, and that preventing cancer is, I believe, a good thing.

I'm also delighted that the article indicates some of the types of cancer we have clearer evidence for. You probably saw the recent study on throat cancer and its putative links to HPV, oral sex and kissing, but there's some suggestive data beyond even the several types of cancer ABC lists, e.g, the study I linked a few months back on lung cancer, probably too early to push that link as certain (it is far from certain), but my intuition is that we'll see that link more cleanly evidenced in coming years as well.

The Los Angeles Times notes another study showing that Gardasil works in men, too.

Unfortunately, they conclude:

By blocking penile and anal warts, the vaccine can reduce the incidence of the related cancers. But the incidence of both of those cancers is low, so critics of the vaccine argue that the public health benefits are not sufficient to justify the high cost of widespread vaccination for any male group other than, perhaps, homosexuals. Proponents, however, argue that women contract HPV from men and that vaccinating men bolsters herd immunity, thereby protecting women.

Which is fine as far as it goes, with the information provided there, there is a fair question. What's omitted, however, is the evidence that HPV, and perhaps some of the same strains of HPV that are protected against in this vaccine, are involved in even *more* forms of cancer. For example, HPV has been implicated as the second-largest cause of lung cancer in a study that discovered correlations between lung cancer and the incidence of HPV 16 and HPV 18. So we have this virus, and it causes cancer in some bits of tissue in women, and we know that, and we see a certain correlation, and yeah, we see that same correlation in men and women with lung cancer. It may be scientifically accurate to say that we don't know that there's causation there for lung cancer, but you'd have to be a complete moron to think that causation was improbable. HPV 16 is also, according the the WHO, the cause of a variety cancers of the mouth and throat.

While many of these cancers are, too, rarer than cervical cancer, they add up. While everyone should cautiously consider the risks, costs and potential benefits of this as well as any other sort of medical procedure, the weak defense of the potential value of this vaccine in the Los Angeles Times is, I fear, misleading and potentially harmfully so.

When I was growing up, "Still no cure for cancer." was a catch-phrase for the inability of science to provide anything we might want. Here we have not a cure but (in some ways, better) a preventative for cancer, for perhaps a dozen variety of cancers, but we're giving it less respect than Rodney Dangerfield. I'm baffled.

While Gardasil was approved for use in preventing genital warts in men in 2009, I note that last month the FDA extended it's approval of Gardasil to include the use of it in men to prevent anal cancer. Well done.

Gardasil effective at preventing anal cancer in men who have sex with men.

Yesterday at EUROGIN, Merck annouced results of a Phase III clinical trial of men who have sex with men. The study provided data which suggests that Gardasil is effective 78% effective at reducing the rate of anal intraepithelial neoplasia, a precursor to anal cancer. There's a pretty large confidence interval on the effectiveness percentage (roughly 40-90%), but the effect is signficant in any case.

In addition to anal cancer, HPV strains have also been linked to cervical, neck, mouth, throat, esophogus, penile, vaginal and lung cancers, as well as a variety of kinds of warts.

HPV second biggest cause of lung cancer?

Y'know how I've been mentioning that HPV isn't just an issue of cervical cancer, but also neck, mouth, throat, esophogus and penis cancers? Now perhaps we can add lung cancer to that list.

A study out of the Institute of Pathology, published in the journal "Lung Cancer" (v.65, issue 1) finds a strong linkage between HPV and lung cancer.

The authors conclude:
The data suggest that HPV is the second most important cause of lung cancer after cigarette smoking and strongly argues for additional research on this issue.

While nobody is saying that HPV vaccines are a cure, nor are they a single solution to cancer numbers of types of cancer some strains of HPV are involved in is very telling. I suspect that developing widespread herd immunity to carcinogenic HPV strains will have a statistically significant effect on cancer in the United States and the World. What's not to like?

FDA Panel Recommends Approval for Men 9-26

Today, an FDA panel recommended that the cancer vaccine Gardasil be approved for use in men and boys aged 9-26.

According to Anna Giuliano, an independent scientist at Moffit Cancer Center in Tampa, Florida, and the trials' principal investigator, "The data clearly demonstrates that there was a benefit to men in receiving Gardasil. Overall, we saw a 90 percent reduction in disease -- genital warts and pre-cancerous lesions -- caused by HPV in men and an 89 percent reduction in genital warts incidence.

Get that, a 90% reduction in pre-cancerous lesions for the types of cancers under study.

The FDA will likely follow the panel's recommendation. This is great news, let's be clear. This is a vaccine for some types of cancer, it's appears to be quite safe and appears to be effective in men. (As was true with women, the focus of early research has been on younger age cohorts, the lack of a recommendation for men above 26 does not mean that there's evidence against its use at ages above 26, it means that there's simply not significant data there yet.)

This is also good news epidemiologically. If you want to wipe out a virus that causes at least a half-dozen types of cancer (cancer-causing HPV strains have been linked to cancer of the cervix, throat, mouth, anus, penis and neck), and the disease is sexually-transmitted, you're going to have a lot easier time if you don't exclude half the population you're trying to protect. To be clear, I'm not criticizing caution and this phased approach to using the vaccine, but in the long run, the more the vaccine is used across wider parts of a population the more that everyone (at least anyone that ever comes into contact with anyone else) will benefit.