Cervical cancer ranks at #8 for the cancers women face most often. More than 12,000 new cases were expected to be diagnosed in 2014; almost 5,000 women were expected to die from it (actual numbers are still being calculated). The median age for diagnosis is 48 and Hispanic women are much more likely to develop this cancer than other women.
The Pap Test
The death rate of cervical cancer dropped dramatically, by approximately 74%, after the introduction of the Pap test in the 1940s. Named for its inventor, George N. Papanicolaou, the Pap test (once called a Pap smear) involves examination of cells extracted from the neck of the uterus (cervix). These cells are analyzed by one of two methods:
- Visual examination of cervical cells on a glass microscope slide
- Laboratory analysis of cells placed in a liquid preservative (an automated liquid-based Pap cytology test)
Women are urged to get Pap tests routinely for earliest diagnosis if cancer is present. Routine screening is recommended from the time a woman reaches sexual maturity until death. When detected early, cervical cancer has a high cure rate.
The HPV Test
Infection with the human papilloma virus (HPV) causes genital warts and approximately 70% of all cervical cancers. The US Centers for Disease Control and Prevention estimate that more than 80% of all women in this country will have contracted one or more strains of this highly contagious sexually transmitted virus by the age of 50. Approximately 20 million Americans are thought to be infected with HPV at any given time. Some infections clear themselves up with no lasting effect, some produce treatable symptoms, some cause cervical cancer.
The automated liquid-based Pap cytology test can detect the virus but the microscope-based Pap test does not. Since its development, the automated test is more commonly used than the microscopic exam but a new DNA-based test for HPV (not cancer) was approved in 2014.
Although an HPV vaccine was approved for use in the US in 2006, vaccination does not rule out the need for routine HPV or cervical cancer screenings. The vaccine does not protect against all strains of HPV.
Since approval of the DNA test for HPV, a growing body of medical professionals is calling for eliminating the Pap test as the first line of cancer screening and using only the DNA HPV test instead. Advocates of the DNA test say it will detect the virus earlier than the Pap test can detect abnormal, possibly pre-cancerous cells. This group of medical professionals has published a clinical commentary in the journal, Gynecologic Oncology, expressing their desire to revise the cervical cancer screening protocols currently in place.
HPV does cause many forms of cervical cancer but it is not the only cause. Also, every HVP infection does not become cancerous. It’s for these reasons that critics of the proposal for the DNA test want to continue using the Pap test as the first-line of screening for cervical cancer.
Regardless of which test is used, presence of abnormal cells in the cervical area calls for further testing that perhaps includes a biopsy, surgery, chemotherapy, or radiation treatments. Abnormal cells don’t always signal cancer. Critics of the DNA-only screening fear the DNA test will subject too many women to the physical and emotional trauma of expensive, unnecessary advanced diagnostic maneuvers that can be quite painful. They also fear the DNA test will overlook cervical cancers from causes other than HPV.
- Huh, Warner K. "Use of primary high-risk human papillomavirus testing for cervical cancer screening: Interim clinical guidance." Gynecologic Oncology (2015). Web. 14 Jan. 2015.
- "Pap and HPV Testing." National Cancer Institute. National Institutes of Health, 9 Sept. 2014. Web. 14 Jan. 2015.