Aug
11
2018

HPV Testing For Cervical Cancer

HPV testing for cervical cancer is more sensitive than the traditional Pap test. For years physicians recommended the traditional Pap test once a year to prevent cancer of the cervix. But a few years ago a new cervical cancer screening test, namely the HPV test made the news. It stems from the observation that cancer of the cervix develops in 99.7% of women who test positive for the HPV virus. There are many types of HPV, here we are interested in the few subtypes that produce cancer (carcinogenic HPV virus).

Transmission of the HPV virus between men and women

The human papilloma virus transmits from males to females through bisexual contact. The problem starts when he develops HPV lesions on his penis. Without him wearing a condom, the contact with her cervix during sex can transmit HPV to her cervix. Both partners are not aware of the transmission of that virus, as it does not cause any symptoms. HPV invades the superficial skin layer of the cervix in the woman. In the man HPV will invade the skin of the glans of the penis. After certain incubation time it causes transformation into cervical cancer in the woman. Strangely enough it does not cause cancer in the male. However, in both sexes HPV virus is in the mucous membranes and can contaminate the other sex’s genital.

A recent study comes from UBC Vancouver, British Columbia, which compared the Pap test with HPV testing.

Details of the Vancouver study on HPV testing for cervical cancer

On July 3, 2018 this study appeared in the medical journal JAMA.

19,009 women were part of this randomized clinical trial. With HPV testing only 2.3 cases per 1000 women of early cervical cancers were present four years later. Using the traditional Pap test this figure was 5.5 cases per 1000 women after 4 years. 224 clinicians participated in this study. Women were recruited for this study from January 2008 to May 2012. Follow-up took place till Dec. 2016. The participating women in this study were 25 to 65 years of age.

In 2017 in the US there were still 12,820 women in the United States who got cancer of the cervix. Approximately 4210 are dying from this disease every year. Many women do not like to take the Pap test or the HPV testing. There are compliance problems with either one of these tests.

Significance of this trial regarding HPV testing for cervical cancer

The newer HPV testing was superior to the regular Pap test. The HPV test was more sensitive and resulted in much lower cancer rates after 4 years of follow-up. Every woman would have an HPV test every 4 years. In this case we likely would see cervical cancer go to the bottom of cancers that kill women. The reason for that is that HPV testing and colposcopy pick up cancers much earlier. This leads to a more effective treatment of cervical cancer. After 4 years much less cancer of the cervix was found when the researchers tested again using HPV testing.

Implications of HPV testing for cervical cancer

In third world countries

Many 3rd world countries do only the HPV testing. At the time when this decision was made, it was unknown that they had actually chosen the better method to test for cancer of the cervix. Now this trial reassures all the health care providers in 3rd world countries that they should continue with the program, and they only have to do the test every 4 years, not every 2 years, which makes it even more cost effective.

Implications for the US

In the US so far the recommendation was to do both the regular Pap test and the HPV test simultaneously. This trial, however, says that this is not necessary. It would be better to use the more sensitive HPV test and abandon the more expensive and less sensitive PAP test. In 2012 a taskforce recommended to do the Pap smear in women age 21 to 65 every 3 years. The taskforce further recommended to women age 30 to 65 that they screen with a combo of cytology and HPV testing every 5 years. The lead investigator, Dr. Ogilvie said: “Offering women HPV [testing] for cervical cancer screening detects more precancerous lesions earlier, and also a negative HPV test offers more assurance that women will not develop precancerous conditions in the next four years,” she said. “This can mean that women may need less frequent screening but have more accurate results.”

What other doctors are saying about HPV testing for cervical cancer

Comments by Dr. Kathleen Schmeler

Dr. Kathleen Schmeler said that the study was “well-designed” and provided a much-needed comparison of Pap versus HPV testing. She is a gynecologic oncologist and at The University of Texas MD Anderson Cancer Center. She was part of the new research. Dr. Schmeler added: “The bottom line is that this could really potentially simplify how we screen women and have it be more effective and not quite as complicated and burdensome — and opens the door for doing just HPV testing, which is actually what’s currently recommended by the World Health Organization for countries that don’t have Pap testing capabilities,”

Comments by Dr. Stewart Massad

Dr. L. Stewart Massad Jr. is a professor of obstetrics and gynecology in the division of gynecologic oncology at Washington University School of Medicine. He wrote an editorial to the study in the JAMA. He wrote: “What will replace the Pap test? In 2012, the American Cancer Society endorsed co-testing with cervical cytology testing and HPV testing at 5-year intervals as the preferred strategy for screening women 30 to 65 years of age because this approach combines the sensitivity of HPV testing with the familiarity of traditional Pap testing,” He then went on to say: “However, the addition of cervical cytology testing adds little to the accuracy of HPV testing while increasing cost and false-positive results. In 2018, organizations that develop cancer screening guidelines are wrestling with whether to recommend replacing co-testing with primary HPV testing as the optimal screening strategy.”

Future dilemma

In view of all those comments the regulatory agents will have to come up with solutions for what is in the best interest of women for testing for cervical cancer.

HPV Testing For Cervical Cancer

HPV Testing For Cervical Cancer

Conclusion

A large randomized clinical trial in Vancouver, BC, Canada has compared screening methods for cancer of the cervix in women. Half of the subjects underwent screening by the newer HPV tests that checks for the presence of HPV virus. The other half received conventional screening by the Pap test (a cytological screening test.) The result was that the HPV test was more sensitive and resulted in less early cancer tests 4 years down the road. With the conventional Pap test there were more than double the amount of abnormal cells present 4 years down the road, which makes the Pap test less safe compared to the HPV test.

It appears from this trial that the Pap test is no longer a choice, except for colposcopy procedures that take care of early cervical cancers. But for screening in general HPV testing every 4 years is all what every women needs for her protection.

Related topics:

  1. Cancer rates increased in women.
  2. Catch cancer early.
  3. HPV testing was described in this blog in 2013: Low cost cervical cancer screening.
Jul
13
2013

Low Cost Cervical Cancer Screening

Introduction

Recently a low cost cervical cancer screening method was developed in India. About 25% of all invasive cancers of the cervix in the world are contributed from India as screening for cervical cancer is not practiced there on a large scale. Many screening methods for cervical cancer became more elaborate over the years as I describe here.

However, these screening methods are expensive.  They require a doctor who does the Pap test (or takes a swab for DNA testing) and a cytological laboratory. In addition, this service requires a gynecology service back up for positive cancer cases. In the Western world these services are in place and are responsible for improved cervical cancer survival rates.

The American Cancer Society (ACS) guidelines

The ACS guidelines state that cervical cancer screening should begin 3 years after the initiation of sexual intercourse. Women benefit from  screening every year for the first 3 years. If 3 consecutive screening results were normal, then a Pap test once every 2 or 3 years would suffice. Because of the Pap test the incidence of cervical cancer has continually dropped in the Western world as seen in this image. Compare this to the next link, which shows India as the main part of the undeveloped countries as a graph on top of the graph for cervical cancer incidence of developed countries.

Cervical cancer is due to a chronic HPV infection

With the new insight that cervical cancer is due to a chronic HPV infection, mostly due to strains 16 and 18 there are shifts in screening methods even in the Western world as DNA tests for HPV can identify a high percentage of cases that would otherwise go on to develop cancer of the cervix. However, due to cost issues with regard to DNA testing for HPV the Pap test is still the method of choice in many Western countries including the US.

Low Cost Cervical Cancer Screening

HPV16 and HPV18 were very prevalent in the cervical cancers found, not only in premalignant lesions, but also in advanced cervical cancer as this study showed. The authors concluded that vaccination with the HPV vaccine (e.g. Gardasil) would have a significant impact on the prevention of cervical cancer, particularly in a country like India where a regular screening program is not yet in place.

An inexpensive test for cervical cancer screening

In 2009 there was a publication in the New England Journal of Medicine that investigated three screening methods for cervical cancer, the familiar Pap test (cytology testing), human papilloma virus (HPV) testing and visual inspection after staining with 3-5% acetic acid. In Western medicine the Pap test is done first and if suspicious cancer cells are detected, this is followed up with colposcopy where acetic acid staining is done and a biopsy is taken from the suspicious area. After this one-time test in 1999 the patients of this study received follow-up again (10 year follow-up).

The direct DNA test for HPV

The direct DNA test for HPV caused a 52% reduction of deaths from cervical cancer in comparison to the control group. The other two test methods, done as a single test (cytology testing and acetic acid visualization) did not result in reduced mortality when compared to the untreated control group after 10 years. However, a 15-year follow-up of a one-time screening with the acetic acid test showed a reduction of 31% in the cervical cancer death rate (reduction from 16.2 women per 100,000 to 11.1 women per 100,000) as reported recently at the annual meeting of the American Society for Clinical Oncology. Shastri and co-workers, the authors of this study, estimate that this would translate into prevention of 22,000 cervical cancer deaths annually in India and if instituted across the developing world it would save 73,000 lives annually.

Is cervical cancer screening effective?

A meta-analysis of several randomized studies regarding the effectiveness of cervical cancer screening in reducing mortality from invasive cervical cancer was published in May 2013 and found that cancer screening is indeed very effective.

In most studies Pap tests (cytology testing) or DNA tests for HPV led to a 62% to 65% reduction of mortality from invasive cervical cancer 10 to 15 years later. The protective effect from screening lasted about 5 years. However, the practice of doing Pap tests or DNA/HPV testing every 1, 2 or 3 years is safer than waiting 5 years between tests as there is a cumulative protection to the point of preventing almost 100% of cervical cancer over the years with regular testing.

Staining with 3-5% acetic acid and visual inspection

For India and other development countries the inexpensive visual inspection method to screen for cervical cancer after staining with 3-5% acetic acid is better than not doing any screening at all. A nurse can readily learn this type of screening. Only patients with positive or questionable screening results receive a referral to a treatment center.  The best results were possible through a combination of this screening method and vaccinating girls with an HPV vaccine. This leads to a more complete prevention program for cervical cancer in these countries that could otherwise not afford screening. The Bill & Melinda Gates Foundation is helping to reduce the cost of the HPV vaccine to about $4.50  from about $170 in the US, which will allow mass vaccination in development countries in the near future.

What other cervical cancer prevention is available?

As pointed out earlier it is now evident that most cases of cancer of the cervix are due to chronic HPV16 and HPV18 infections. Teens can acquire these and the HPV viruses linger on unnoticed within the affected cervical cells. However, 10 to 15 years later they can manifest themselves as cancer of the cervix . This long latency period allows the physician to screen for this before it becomes invasive and is more difficult to treat. What has become more evident only in the past few years is that other human tissues can get infected with papilloma virus as well and turn cancerous over the years.

Cancers that can occur from sexual contact

Oropharyngeal cancer, anal cancer, penile cancer, vulvar and vaginal cancer and even some forms of throat cancer and lung cancer can develop from intimate contact with a person who is HPV positive. Researchers confirmed that oral cancer is now more than 70% related to HPV infection rather than to cigarette smoking or alcohol as in the past. Sexual practices have changed over the past decades with oral sex being more common. This likely is the reason why HPV caused more oral cancers in recent years.

Finger pointing is not constructive

Finger pointing is not uncommon when it comes to a rational discussion of HPV transmission, but it has become apparent that males are often the ones who may be spreading HPV unknowingly through promiscuous sexual activities. Both heterosexual and homosexual activities will spread HPV. But the more promiscuous a woman is, the more she will also contribute to HPV infections in the population.

HPV vaccines Gardasil and Cervarix

When the pharmaceutical industry developed the HPV vaccines Gardasil and Cervarix many religious groups have spoken out against vaccination, as this would “encourage promiscuous behavior”.  I look at this question from the point of view that lives can be saved down the road by preventing several cancers as indicated, and that is what counts on the long-term. In this context it makes a lot of sense that not only females get a vaccination, but also males to interrupt the infectious chain and this trend can now be seen as it is adopted by several jurisdictions.

Conclusion

Cervical cancer screening is still very necessary doing a Pap test or a DNA/HPV test. Screening is necessary more often than every 5 years as pointed out. Most women need a Pap test every 2 to 3 years. HPV vaccination with Gardasil and Cervarix for boys and girls prior to sexual relations is very preventative, but still does not mean that screening should be stopped. Cervical cancer is the cancer that has the longest medical history of moving from a very prominent deadly disease (back in the 1960’s) to a cancer that can now be cured and prevented.

References

  1. Causes of cervical cancer: http://nethealthbook.com/cancer-overview/cervical-cancer/causes-cervical-cancer/
  2. HPV vaccine: http://www.mayoclinic.com/health/cervical-cancer-vaccine/WO00120
  3. Review of cervical cancer: http://www.nethealthbook.com/articles/cancer_cervicalcancer.php#topoftable

Last edited Nov. 7, 2014

Oct
01
2005

More Education Needed About Ovarian Cancer

Campaigns that inform about breast cancer are abundant in the media, but the one cancer which may be the most fatal of gynecologic cancers is silently at work, killing more than 60% of women diagnosed – ovarian cancer.
It is also the cancer women know shockingly little about, and most women cannot identify its symptoms. Dr. Barbara Vanderhyden from the University of Ottawa, Canada confirmed in a study, that there are a lot of misconceptions about the disease. One in three women falsely believe that a Pap test screens for ovarian cancer. Remarkably, 12% of Canadian women claim that they have never heard about the disease, and only 35% consider themselves well informed. Even more problematically, women 50 years and older-those with the highest risk for ovarian cancer- are significantly less likely to be aware of their risk for disease than their younger counterparts. 71% of women think that ovarian cancer mainly affects women under 50 years of age.
In the view of the findings that 96% of the women could not identify a combination of the most common symptoms of ovarian cancer, it is of great importance that more education and information is needed. Women as well as their health care providers have to be vigilant about early warning signs and symptoms. The most common warning signs and symptoms for ovarian cancer are bloating, abdominal pain, changes in urinary frequency, weight fluctuation and nausea.

More Education Needed About Ovarian Cancer

More Education Needed About Ovarian Cancer

Diagnostic tests involve a bimanual examination by a physician, which is needed for all women, including those who did have a previous hysterectomy. The other test to consider would be an abdominal ultrasound.

More information about ovarian cancer: http://nethealthbook.com/cancer-overview/ovarian-cancer/

Reference: The Medical Post, September20, 2005, page 47

Last edited October 29, 2014