HPV Oral Cancer and Cervical Cancer: A Study
Guest: Dr. Andrew Lawson, Biostatistics & Epidemiology, MUSC
Host: Dr. Linda Austin – Psychiatrist, MUSC
Dr. Linda Austin: Dr. Andrew Lawson is Professor in the Division of Biostatistics and Epidemiology here at the Medical University of South Carolina. He has a very interesting specialty in which he works with researchers and clinicians looking at the geographical distribution of illnesses and diseases across the United States. Dr. Lawson, let’s take an example and, maybe, you could help us understand what your contribution is in a particular research study.
Dr. Andrew Lawson: Currently we have a study which was initiated by Boyd Gillespie, a specialist in oral health and oral cancer at MUSC. The study was started by the observation that a number of patients tending clinic seemed to have HPV-related oral cancers, and there appeared to be a particular demographic distribution for these patients. Dr. Gillespie wondered whether there was some evidence for there being behavioral links related to the outcome for these patients: i.e. the oral cancer and lifestyle behaviors.
Dr. Linda Austin: So, let’s go a little bit deeper into that. Specifically, what behaviors did he think might be associated with the spread of HPV?
Dr. Andrew Lawson: Well, it’s known that HPV is in large part responsible for cervical cancer. The thought was that if people are presenting with HPV oral cancers, there might be some sexual behavioral link between the cervical cancer and the oral cancer, so this could be something to do with sexual practices between couples in general, and the population. The particular reason that Boyd Gillespie actually observed this was that there appeared to be a large difference between the number of cancers that presented themselves among whites and African-Americans. The pattern is very different between African-Americans and whites. And it was thought that there may be some behavioral difference in terms of the likelihood of, say, a white person getting oral cancer, or HPV-related oral cancer, and an African-American person getting that cancer.
Dr. Linda Austin: And, specifically, is it more, or less, common in African-Americans?
Dr. Andrew Lawson: It’s more common, actually, in whites than African-Americans.
Dr. Linda Austin: More common in whites?
Dr. Andrew Lawson: And the assumption is that there’s a different behavioral pattern. Basically, the behaviors of white people are somewhat different from the behaviors of black people, in South Carolina in particular.
Dr. Linda Austin: Specifically, sexual behaviors?
Dr. Andrew Lawson: Yes.
Dr. Linda Austin: So, for example, oral sex?
Dr. Andrew Lawson: Yeah.
Dr. Linda Austin: It kind of begs the question that that may be more prevalent in white people and therefore may lead to more cancer.
Dr. Andrew Lawson: Yes.
Dr. Linda Austin: It almost sounds like something your mother would have warned you about.
Dr. Andrew Lawson: Yes, indeed.
Dr. Linda Austin: So now, where do you come in on that, as a statistician? Help us understand that.
Dr. Andrew Lawson: Well, basically, what we decided to do when we heard that there might be a link between the two, we decided to look at the geographical distribution of these cancers, the distribution between oral cancers and cervical cancers, to see if there’s actually a link between oral cancer and cervical cancer in the population. You might think, if there is a link, that areas which have very high cervical cancers would also have high oral cancers, HPV-related, and so on.
So, our geographical studies, our statistical studies of the geography, would help to isolate these patterns. It turns out, in some of our preliminary studies, there are definite differences between African-American and white populations. And there is a suggestion that these could be behavioral, but the results are somewhat equivocal, so we haven’t quite got the answer yet. We think we need to do further work.
Dr. Linda Austin: So then, you come in as the numbers cruncher on that, looking at large tables of numbers, and so forth, generated by the researchers, to see if, indeed, the pattern is statistically significant?
Dr. Andrew Lawson: Yeah. That’s right. What we’ve done in this study is to take data that’s actually publicly available from SC DHEC and do some analysis of their data, at the level of counties, and so on, collecting counts of disease in counties. And what we’re planning to do in the future is to go to a much finer level, taking clinical data from Boyd Gillespie’s patients and look at their actual behaviors via a questionnaire survey, and so on.
Dr. Linda Austin: Do you have a hunch as to what direction the data will go?
Dr. Andrew Lawson: We certainly believe that there are strong differences. I think it’s probable age-specific in the sense that if you have a very old static population in some part of the country, you’re going to find a bigger difference between them and a population that’s sort of younger in its demographic, possibly, also, white. So, a mobile population, say, in South Carolina compared to a relatively static African-American population will show big differences.
Dr. Linda Austin: You know, it’s really a fascinating question because it’s pretty well- known that rates of teenage pregnancy are going down, and teenagers are more frequently resorting to oral sex as a means of birth control. It’s rather disappointing, or alarming, to hear that, in fact, that may be leading to another sort of problem, which is oral cancer.
Dr. Andrew Larson: There are kind of two things there. There’s quite a lot of campaigning against vaccination for girls for cervical cancer. But if the so-called safer sexual approach is to actually adopt oral sex practices, then, of course, that’s not necessarily going to be true if this study shows up to be positive.
Dr. Linda Austin: Dr. Lawson, can you clarify that a little bit for us? What you said is that there are some people campaigning against the HPV vaccination. Your concern, then, is what?
Dr. Andrew Lawson: My concern is that the campaigning against the vaccination, which is done on ethical grounds by the campaigners, might lead to more cases of oral cancer, as well as cervical cancer.
Dr. Linda Austin: Very interesting. Thank you very much, and good luck with this research.
Dr. Andrew Lawson: Thank you.