Cervical Cancer
Applied Epidemiology
Brianna Loeck
ABSTRACT
Cervical cancer has become a leading cause of death in women. Cervical
Cancer is primarily developed from the Human Papillomavirus (HPV), which
is contracted through sexual contact. Several women are not aware they
have HPV, this is why screening tests such as Pap Smears and HPV tests
were created to detected pre-cancerous cells early on to prevent spreading
to Cervical Cancer.
Unfortunately every human being may be at risk for some type of cancer, whether
it is genetic, poor hygiene or unhealthy habits. One of the cancers that all women are at
risk for is cervical cancer. The human papillomavirus (HPV) is the main cause of
cervical cancer. HPV is a common virus that is passed from one person to another during
sex. At least half of sexually active people will have HPV at some point in their lives, but
few women will get cervical cancer.
HPV is categorized into low-risk and high-risk types. The low-risk types which
include strains: 6, 11, 42, 43, 44, 54, 61, 70, 72 and 81 are rarely found in cancers. Highrisk types include strains: 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 68, 73 and 82 and
which have been found in cancers of the cervix, vagina, vulva, and penis. The majority
of cervical cancers (80%) are caused by just four HPV strains, which are 16, 18, 31, and
45 (ASCP, 2012).
Cervical cancer and other HPV related cancers can all be prevented by regular
screening exams such as the Pap test and the HPV DNA test. According to
WomenHealth.gov (2009), “The Pap test, also called a Pap smear, checks for changes in
the cells of your cervix. The cervix is the lower part of the uterus (womb) that opens into
the vagina (birth canal). The Pap test can tell if you have an infection, abnormal
(unhealthy) cervical cells, or cervical cancer.
WebMD (2013) states, that a human papillomavirus (HPV) test is done to find a
high-risk HPV infection in women who had a Pap test that showed abnormal cervical
cells called atypical squamous cells (ASC) and checks for the genetic material (DNA) of
the human papillomavirus. “Screening tests can find early signs of disease so that
problems can be treated early, before they ever turn into cancer” (CDC, 2012). This is
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why it is extremely important for women to be screened regularly to prevent such cancers
from occurring.
There are ways to reduce the risk of contracting HPV which then may have
potenial to be at risk for cervical cancer. In 2006, Gardasil (HPV4), an HPV vaccine was
introduced to protect against the exposure to certain strains such as 16, 18, 6 and 11. It is
strongly recommend that girls and women between the ages of 9 and 26 years old receive
the vaccination. “While the vaccine does not prevent infection with all types of HPV, it
provides protection against the HPV types associated with 70% of cervical cancers (16,
18), and 90% of external genital warts (6, 11)” (ASCP, 2012).
Newer screening technologies have been developed such as liquid-based cytology
(e.g, ThinPrep) to improve the sensitivity of screening. “One advantage of liquid-based
cytology is that HPV testing be done on the same preparation; one disadvantage is that
liquid-based approaches are more expensive than conventional Pap testing. No study has
examined whether liquid-based cytology actually reduces the number of women dying of
cervical cancer compared with conventional Pap testing” (NCI, 2013).
According to CDC (2012), all women are at risk for cervical cancer, but it is rare
in women younger than 30 years of age. The average age at diagnosis is 47 years old. In
2007, 12,280 women in the United States were told they had cervical cancer, and 4,021
died from the disease. CDC provides a graph for cervical cancer incidence and death
rates by race and ethnicity in the United States per 100,000 from CDC (Refer to
Appendix, Figure 2).
The graph shows that Hispanic women have the highest incidence rate of cervical
cancer, followed by black, white, and American Indian/Alaska Native, and Asian/Pacific
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Islander. Overall, 7.9 out of every 100,000 women were diagnosed with cancer in 2007
(CDC, 2012). However, black women have a higher death rate, followed by Hispanic,
American Indian/Alaska Native, white, and Asian/Pacific Islander women. Overall, 2.4
out of every 100,000 women died from cervical cancer in 2007 (CDC, 2012).
Not every women needs to obtain regular Pap smears. Women over age 65 who
have had 3 normal Pap tests and in a row and no abnormal test results in the last 10 years
and also women who do not have a cervix and are at low risk for cervical cancer.
“Cervical cancer mortality, usually occurring among unscreened women, increases with
age, with the maximum mortality for white women between age 45 years and 70 years,
and for black women in their 70s. Mortality among women with negative Pap screening
is low at all ages” (NCI, 2013).
Cervical cancer used to be the leading cause of cancer death for women in the
United States. However, in the past 40 years, the number of cases of cervical cancer and
the number of deaths from cervical cancer have decreased significantly. Receiving
regular Pap tests is the best thing a woman can do to prevent cervical cancer.
As a public health professional and an epidemiologist there are a few ethical
issues that may arise regarding HPV. One issue is having young girls receiving the
recommended vaccines such as Gardasil to help protect and prevent the more serious
HPV strains that cause cervical cancer. By doing this, some parents believe that this will
begin or increase their sexual activity. It frightens the parents, so they would rather have
their daughters not receive the vaccine. Another issue regarding receiving the HPV
vaccines is that the actual vaccine might do more harm than good. There are several
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people out there that believe that vaccines do more harm than good and put one at higher
risk for developing mental, emotional, or physical issues such as autism, for example.
I definitely believe that performing Pap smears should start at an earlier age due
to the fact that girls are becoming more sexually active at a younger age. With that being
said, I believe it’s important for them to receive the recommended vaccines as well.
Personally, that is my opinion, but I am sure several parents would disagree. I
could understand if the girl was very low risk and tested negative on the Pap smear, then
it is obviously not necessary. However, for a girl perhaps in the southern states of the
United States it could be mandatory, because southern states such as Texas, Oklahoma,
Arkansas, Tennessee, Kentucky, and Alabama have a higher HPV incidence rate
compared to other states in the United States according to CDC.
As a public health professional I would target my main focus and concentration
on these such states to do further research about why and how these states are labeled
higher for incidence rates and also for death rates (Refer to Appendix for maps). I
believe the first step is to really educate about HPV and/or other STD’s that can lead to
cancer. Teenagers need to be educated about these things, because it is real life and it can
happen to anyone at any age. Proper protection and prevention is the key to decrease
prevalence rates and even death rates from rising or remaining the same. The goal is to
decrease these rates, and by doing so it education and knowledge.
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Appendix
CDC 2012
Incidence Rate of Cervical Cancer 2009 (CDC, 2012)
Death Rate for Cervical Cancer 2009 (CDC, 2012)
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References
American Society for Colposcopy and Cervical Pathology. (2012). Natural History of
HPV. Retrieved from
http://www.asccp.org/PracticeManagement/HPV/NaturalHistoryofHPV/tabid/5962/Defau
lt.aspx
Center for Disease Control and Prevention. (2012). Basic Information about HPVAssociated Cancers Retrieved from http://www.cdc.gov/cancer/hpv/basic_info/
National Cancer Institute. (2013). Cervical Cancer Screening. Retrieved from
http://www.cancer.gov/cancertopics/pdq/screening/cervical/HealthProfessional/page2#Se
ction_226
WebMD. (2013). Human Papillomavirus (HPV) Test. Retrieved from
http://www.webmd.com/sexual-conditions/hpv-genital-warts/human-papillomavirus-hpvtest
WomenHealth.Gov. (2009). Pap Test Fact Sheet. Retrieved from
http://womenshealth.gov/publications/our-publications/fact-sheet/pap-test.cfm#b
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