Michael Douglas has revealed that his throat cancer was caused by HPV. This confession won him plaudits. But a few days later, Michael Douglas’s publicity agent has denied that this is what the actor had said and that he was in fact making a general point about HPV causing throat cancer.
In this Podcast, Victor Ponsford talks to Dr. Anne Szarewski, Clinical Senior Lecturer at the Wolfson Institute, Queen Mary, University of London, who has been arguing since 2005 that both men and women should be immunised against the Human Papillomavirus. Up until now, HPV has most often been identified as a cause of cervical cancer. Indeed it is the second most common cancer amongst women worldwide, according to the World Health Organisation. However, it should not be seen as a woman-only issue. As this interview with Dr. Szarewski suggests, it is something that affects us all.
Dr Szarewski has a longer article on this subject on The Conversation website.
Victor began by asking Dr. Szarewski how HPV spreads.
Anne Szarewski: HPV is basically spread by skin to skin contact and that’s something that people often are confused about because people think you have to have penetrative sex to catch what is in effect a sexually transmitted infection; but unlike most other sexually transmitted infections, HPV is basically transmitted by skin to skin contact, so any skin contact can actually transmit it.
Victor Ponsford: What percentage of people have had HPV during their life?
AS: Well it’s been estimated that basically 80% of us will catch HPV at some point in our lives, but for most people it actually doesn’t matter because just like a cold – you know we’re all going to get a cold – the vast majority of us are simply going to clear that viral infection with our own immune system and it goes away. And in the case of HPV you never even know you had it and of course, in the case of a cold, you do. It’s only about 10% of people who catch HPV that don’t actually get rid of it and it’s those 10% who can develop persistent HPV infection and it’s from that little pool that you’re going to get the people who are actually in danger of getting cancer.
VP: What are the types of HPV that cause the 10% to develop cancer?
AS: Basically, there are about 100 different kinds of HPV, but only about 20 are of any interest in the genital area and of particular interest in cancer. The most important types of HPV for almost all cancers, in fact for all cancers I think, are HPV 16 and HPV 18.
VP: Given the high proportion of people who get HPV, does this make the people who don’t get it the exception?
VP: So it does make sense to vaccinate. But since HPV is a disease that primarily affects women, swhy is it necessary to vaccinate men as well?
AS: HPV is a sexually transmitted infection, so it doesn’t just affect women. Men carry it; they just have fewer consequences from it than women. For women, it causes cervical cancer, and that’s quite a major problem, but in men it can cause penile cancer, anal cancer and, as we now know, oropharyngeal (throat) cancer; so there are perfectly good reasons for vaccinating boys as well as girls.
I think it also sends out a very very bad message to society if we basically say: ‘It’s a sexually transmitted disease, but only women are actually responsible for it, so we’re only going to vaccinate women.’ It kind of sends out that whole thing about: ‘Well if you’re a nice woman, you’re not going to catch it and therefore you wouldn’t need it’. And this has been the problem I think as a result of this policy that there are cultural and religious groups who say: ‘Well, of course our daughters will never ever have sex with anybody other than their husband and therefore they don’t need to be vaccinated’; but what this ignores is the fact that those husbands may not be absolutely faithful to their wives and many have had a sexual experience even before they get married, even if they are completely faithful after they get married. Because the problem with HPV is that, once you catch it, it can just sit there for years and years and you may not know at all that you’ve got it, men can transmit it years after they’ve caught it without even knowing.
VP: And I suppose with what you said about how it can spread through skin to skin, then women don’t necessarily have to have sex with someone to catch it.
AS: Exactly, so even a sort of fumbling around, as can often happen, can actually transmit HPV as well.
VP: That’s interesting. However, people have argued in the past that vaccinating men is an inefficient use of resources, as we are all protected by herd immunity, and that the money used could be better spent elsewhere.
AS: So herd immunity basically is the idea that if you can vaccinate as many people as possible then those few remaining who haven’t been vaccinated will still be protected because everybody around them has been vaccinated. And in the case of HPV in Australia, because the vaccine they used also protects against genital warts, they were able to show that when they vaccinated women – and they had high uptake of the vaccine – the incidence of genital warts in heterosexual men also reduced because of course the women weren’t passing it back to the next partner.
The problem with that is that it can’t help homosexual men. Men who have sex with men can’t possibly benefit from any herd immunity that’s obtained through vaccination of women. And that’s really unfair because men who have sex with men are actually at higher risk than average of things like anal cancer and of course genital warts as well and they cannot benefit from the vaccination of women. This has actually been raised as a social injustice issue by some researchers who point out that you’re now actually denying a treatment that has been shown to work to a minority group. And this is, in fact, a social injustice and I would agree with that, I think it’s extremely unfair.
VP: Yes and another element of social injustice is that certain demographics don’t allow their women to be immunized.
AS: Yes, and I personally think, you see, if we’d said right from the beginning: ‘Everybody gets this vaccine,’ none of these issues would have come up. How many parents have ever questioned why their son gets vaccinated against rubella? Every boy in the country – well, most of them – gets vaccinated with MMR and nobody questions why their son has been vaccinated against rubella, which has no benefit to men whatsoever; it’s purely of benefit to women. The only reason we vaccinate against rubella is because if a woman gets it when she’s pregnant, it can cause damage to the baby.
VP: My next question was about the success rate, but I think you have already mentioned that; but, just to get it separately, what has the success rate been in reducing the number of genital warts in HPV cancer-related cases since immunisations were introduced?
AS: What they’ve shown in Australia is that basically they’ve had almost complete reduction in genital warts in women in the vaccinated cohort and they’ve actually had an 81% reduction in the young men who’ve obviously been sexually involved with those women, so there’s been a 92% reduction in women of the age vaccinated in genital warts and an 80% reduction in men.
VP: Now obviously what started all this interest in HPV recently was Michael Douglas who said that he got throat cancer from the HPV virus. Is there any way of detecting and treating the virus in the throat before it becomes cancerous?
AS: I’m not an expert on throat cancer, but as far as I’m aware, I don’t think there is a particularly good way of screening for throat cancer. The problem is it’s extremely rare and so in actual fact it wouldn’t really even fulfill the criteria for a screening programme frankly because it’s too rare. And I think that’s one of the problems why even Michael Douglas wasn’t diagnosed for quite a while, from what I’ve read, because people just weren’t thinking about it.
VP: Now Michael Douglas is a really interesting case, because I think he should be applauded for citing HPV as the reason behind him getting cancer. However, his publicist has just come out stating that Michael Douglas was in fact talking about cancer generally and not specifically his own. But whatever the case, he said in the same interview that, although oral sex caused his cancer, it was also the cure. Just to be clear, oral sex has no curative benefit, does it?
AS: No, I think that’s just his wishful thinking, quite frankly.
We are grateful to The Conversation for putting us in touch with Dr Szarewski.