The death rate for cervical cancer has dropped by more than 50 percent over the past three decades. Clara Keegan, MD, explains more about the disease, the changes in vaccination and screening that caused the decrease, and what treatment options are available. Listen to the interview or read the transcript below.
UVM Medical Center: Among the good news stories in the field of cancer is the fact that the death rate for cervical cancer has dropped by more than 50% over the past three decades, largely due to increased screening and the use of a vaccine to protect women from HPV, which is often the cause of the disease. Like other cancers, cervical cancer can be well under way before symptoms appear, making the need for screening and prevention critically important.
We’re going to learn a lot more about cervical cancer today from Dr. Clara Keegan, a Family Medicine Physician based at the UVM Medical Center’s practice in South Burlington. She’s also an Assistant Professor at the Larner College of Medicine at the University of Vermont, and a Fellow of the American Academy of Family Physicians. Thanks for coming.
Clara Keegan: Thanks for having me.
UVM Medical Center: I hardly said anything about cervical cancer there. What is it, exactly?
Clara Keegan: Cervical cancer is when the cells of the cervix, the part of the uterus that extends into the vagina, those cells begin to grow in an uncontrollable way. Sometimes that’s limited to the surface of the cervix, but if it starts to invade inside, just like any other cancer, it can spread further into the body.
UVM Medical Center: Is it common?
Clara Keegan: It is less common than it used to be. We really see the most cervical cancer in women who haven’t had adequate screening, and in women who are at higher risk of infectious disease. Specifically, women who are infected with HIV, have a harder time fighting off the virus HPV, so they’re at higher risk for cervical cancer. But women in the developed world, who see their physician and get the routine screening, very rarely get cervical cancer because we can find it so early.
UVM Medical Center: Is it a particularly aggressive cancer?
Clara Keegan: No, it actually develops very slowly over decades. By the time it develops really significant symptoms, which might be bleeding – bleeding would be the most common presenting symptom – by the time it’s developed and it becomes aggressive, the initial treatment is removal of the uterus, but in some cases, it might have metastasized by that time, meaning spread throughout the body, and then it can be a little harder to treat. The nice thing with cervical cancer is that there’s a very clear progression through earlier stages, which are not cancer.
They’re what we call dysplasia, meaning abnormal growth of cells, but not to the point of what we would call it certain cancer. As that process goes over decades, we can pick up the process well before it’s cancer, and with a much smaller excision of the affected area, removal of just part of the cervix, we can prevent cancer from ever developing, and women then don’t need to have a hysterectomy.
UVM Medical Center: On screening, how young are women when they should start having this done?
Clara Keegan: This is a really exciting change in medicine, because most women don’t really look forward to going for pap tests, and the historical approach to cervical cancer screening was that if a woman had become sexually active, she should start having screening. But, we’ve figured out that women who are teenagers, young women, really don’t benefit from pap testing, because the abnormal changes that they might develop at that age – their body will fight them off very quickly on their own. So, we end up doing more testing that isn’t necessary and could potentially cause harm, if we screened teenagers. We now recommend starting screening at age 21.
UVM Medical Center: Regardless of sexual activity?
Clara Keegan: The recommendation is regardless of sexual activity, because the virus can actually be transmitted through processes other than intercourse. It can be transmitted by genital contact and there’s some transmission from mother to child, as well. Much less common, but it is possible to have an HPV infection that persists, that didn’t have anything to do with sexual activity.
UVM Medical Center: So, you start at 21. Is it annual or every five years?
Clara Keegan: It used to be annual. But, again, now we’ve figured out that because of the way the immune system is so active in younger women, we can do screening every three years from age 21 to 29. We also now know that HPV is so clearly linked to cervical cancer that at age 30 we start doing HPV testing along with the pap test. The pap test is a collection of cells, and in the pathology lab, they look at the cells and decide whether they look like dysplasia or something more severe.
If we add on the HPV test and a patient has normal cells, and does not have an HPV infection, then we can do paps every five years. We do that from age 30 to 65. After 65, if someone’s had adequate screening, developing a new HPV infection and then developing cervical cancer in the lifespan remaining is unlikely, so we go on a case by case basis. But, in general, we no longer need to screen after 65 years old.
UVM Medical Center: What’s the age of onset, typically?
Clara Keegan: In younger women in their 20’s, and maybe 30’s, we might see what we call low-grade dysplasia, and then we watch that more closely to see if it developed into higher-grade dysplasia, which can develop at any time in the 20’s, 30’s, 40’s. Most women who are diagnosed with cervical cancer are in their 40’s or 50’s, because it takes that long for the cervical cancer to develop after exposure to HPV.
UVM Medical Center: If you’re just tuning in, you’re listening to Dr. Clara Keegan, Family Medicine Physician, based at the UVM Medical Center practice in South Burlington. She’s also an Assistant Professor at the Larner College of Medicine at the University of Vermont, and a Fellow of the American Academy of Family Physicians. We’re talking about cervical cancer. Aside from sexual activity, what are some other risk factors for this?
Clara Keegan: Smoking increases the risk of having HPV. It’s incredibly easy to get an HPV infection. It’s pretty much 95% of people will have had HPV at some point in their life. That’s women and men. Most people fight it off when they’re younger, because it’s easiest to get as a teenager, and it’s also easiest to fight it off as a teenager.
What we’re watching for on the medical side is those infections that persist over time. Smoking affects the immune system’s ability to fight off the infection, and so then if the infection lasts longer, there’s a higher risk of developing dysplasia. Other conditions that make it harder to fight an infection, like HIV infection, or if someone’s immunosuppressed. For example, if she’d had a kidney transplant and needed immunosuppressant medicines to keep her new kidney safe, that woman would also be at higher risk of a persistent HPV infection that might lead to cancer.
UVM Medical Center: Let’s talk about the HPV vaccine. This is something that I think has developed a higher profile, let’s say, in recent years, because it’s been kicked around a little bit as a political football. But why don’t you give people the basics on the vaccine and when and how it’s administered.
Clara Keegan: The vaccine has been available now for, I think, almost 10 years. First, there was one that just covered the two strains of HPV that are most likely to cause cervical cancer. There are a very large number of members of the HPV family. HPV 16 is the one that’s found in the biggest number of cervical cancers, and HPV 18 is less common, but is found in much more aggressive cancers that might be found at an early age.
So, we’ve had a vaccine against those two strains for quite a long time, and around the initial release of the vaccine, there was also one that covered two other strains of HPV that caused most genital warts. The vaccine doesn’t just protect against cancer, it also protects against genital warts, and we can see that affect very quickly in population studies of people who have received the vaccine.
Now they have released the monovalent vaccine, which covers nine members of the family. So, we’re now providing protection against the nine members of the family most likely to cause the cancer. By giving the vaccine in early adolescence, we’re able to demonstrate a really strong immune response, which is actually much stronger when given in the 11 to 13 age group, than it is when people are older when they get the vaccine. But, it is still valuable to give the vaccine up to even 25 or 26 years old. The idea is, that by causing the body to have a stronger immune response, when it then is presented with HPV after sexual activity is initiated, the body is able to prevent that HPV infection from developing.
So, this can protect from cervical cancer. But we’re also finding that many other cancers of what we call the mucosa – which is the tissue that lines the inside of your mouth or other structures in our body – many of those cancers are related to HPV, so this is cancer of the tonsils, the throat, cancer of the penis, and the anorectal area are all related to HPV. It’s definitely beneficial to vaccinate both young women and young men, because we’re protecting them both from different cancers and also reducing the chance of transmission from one person to another.
UVM Medical Center: You said, “starting in early adolescence,” I think. 11, 12, something like that?
Clara Keegan: Yes. The vaccine is approved for use as early as nine, but we generally include it with the standard vaccination set at about 11 to 12 years old.
UVM Medical Center: Now what about the issue that essentially this raises a conversation with young girls about sexual activity that maybe the parents haven’t wanted to talk to them about yet. Or I think there’s been some concern that, “11? Geez, that sounds young to be doing this sort of thing.” How do you respond to that?
Clara Keegan: I don’t think of it as a vaccine related to sexual activity, as much as a vaccine related to an infectious disease, which is so prevalent in the population. When young women come to me in their 20’s, very worried that we’ve detected an HPV vaccine, they’re very upset that they have a sexually transmitted infection. What I advise them is that really the only way to avoid this virus is to never have sexual contact, or to only have one partner in your whole life whose only had one partner, which is yourself.
When I present this to parents, most parents recognize that while this might sound like a nice ideal that they would want for their child, it’s not necessarily realistic. Just really emphasizing that it’s as easy to get as the common cold, almost. It’s not transmitted in exactly the same way, but it’s just so common in the world, that we really want to give the vaccine when people have the strongest response to it. We’re thinking of it as something that’s going to prevent cancer years from now, which is something that no other vaccine is able to do.
UVM Medical Center: Yes, and there has been a lot more work on vaccines and cancers in recent years. I mean, there’s a lot of hope that that approach is going to be effective, right?
Clara Keegan: Right. It’s hard to see, because as I said, the cancer develops slowly over decades and the vaccine has only been out for less than 10 years, I believe. So, we haven’t seen the response in terms of cancer yet, but we can see, as I said, very quickly we can see a reduction in rates of genital warts. Then we can also see – now that we have 10 years of data -we can see a reduction in the numbers of cases of lower and higher grade dysplasia. We’re already seeing those benefits.
UVM Medical Center: So a couple minutes left, let’s talk about the typical treatment regimen if somebody, unfortunately, develops cervical cancer.
Clara Keegan: If cervical cancer itself is detected, that is managed by a gynecologic oncologist – a specialist in cancers of the female genital tract. Hysterectomy with removal of the entire uterus and cervix is always part of that treatment. Sometimes women might also need radiation and chemotherapy. Women who have had a hysterectomy for cervical cancer, even though they no longer have a cervix, need to have a pap test every year for the rest of their life. So, we need to do an internal exam and collect some cells from the vaginal cuff, where the surgery was performed, to make sure that that cancer didn’t return. If we are able to detect dysplasia, higher-grade dysplasia, then a procedure can be done called a LEEP, or a cone biopsy, where a part of the cervix is surgically removed and they can check to make sure that all the dyplastic cells were removed.
Then we do short interval follow-up after that. So we do pap tests maybe every six months for a little while. Once we’ve determined that things are clear, we go to a slightly longer interval, and pretty quickly, we’re able to return to every five-year screening for 20 years after that procedure was performed. If we find low-grade dysplasia, we just monitor it for a while, because often the body will clear it. So we’re watching for those cases that persist or progress into higher-grade dysplasia, so there’s no treatment needed for the lower-grade disease.
UVM Medical Center: That – what you just described, the hysterectomy and so forth – is that pretty effective?
Clara Keegan: It is effective if the disease has not already metastasized. The women who die of cervical cancer generally have a very advanced disease at the time of diagnosis. That tends to be women who have not presented for care, for evaluation of concerns.
UVM Medical Center: So, big picture – do you sense that, as I was saying at the beginning, it seems to be a good story with the drop in onset, but do you sense that the medical community is going to turn the tide on this one, and people are in the right routines with screening, and so forth?
Clara Keegan: The challenge is that there’s been such a big change recently. Many people are continuing to do the old pattern of pap testing every year. So, it’s really nice when we’re able to tell people we don’t have to do that test as often, and I do see people getting that message more and more. Women tend to not need pap tests as often as they used to, as long as they’ve had adequate screening. For vaccination, I think that we’re getting more and more information about how beneficial it is and we have lagged behind in the United States compared to other countries, such as Great Britain and Australia, which have very high HPV vaccination rates. But as we’re beginning to see the benefits that they’ve recognized in those countries, I think we’re starting to pick up our rates.
One challenge with the HPV vaccine is that you have to get three doses. So, after that initial dose, we need people to come back at one to two month – and then again six months after the initial dose – to complete the series. If someone is delayed and doesn’t get it right in that timeframe, we don’t have to start all over. We can just pick up where we left off. Also, if someone initially got the four strain HPV vaccine, we can finish the series with the nine strain. We don’t have to start all over and re-vaccinate with the one that covers nine strains.
UVM Medical Center: You’ve been listening to Dr. Clara Keegan, a Family Medicine Physician, at the UVA Medical Center’s practice in South Burlington. She is also an Assistant Professor at the Larner College of Medicine at the University of Vermont, and a Fellow of the American Academy of Family Physicians. Thanks very much for helping us understand more about cervical cancer.
Clara Keegan: Thanks, I’m glad to help.