Cervical Cancer Facts and Stats
Cervical cancer was once a leading cause of cancer death for women in the United States. Between 1955 and 1992, however, both incidence and mortality rates declined dramatically due to the introduction and implementation of Pap test screening. Currently, cancer of the uterine cervix ranks 3rd in frequency for both diagnosis and cause of death among the gynecologic cancers1 and 14th for all cancers affecting U.S. women.2 Most invasive cervical cancers are
found in women who have
never been screened or have not had a Pap test within
the past 5 years. Currently, the lifetime risk of developing cervical cancer among U.S. women is approximately 1 in 147.3
There are two major types of cervical cancer: squamous cell carcinoma and adenocarcinoma.
- Squamous cell carcinoma arises in the squamous (flattened) epithelial cells that line the cervix. About 69% of all cervical cancers are of this type.4
- Adenocarcinoma develops from mucus-producing gland cells in the endocervix. It accounts for about 25% of all cervical cancers.4
- Other rarer types comprise the remaining 6%.
Key Statistics:
- In 2012, an estimated 12,170 new cases of invasive
cervical cancer will be diagnosed
in U.S. women.5
- In 2012, an estimated 4,220 U.S. women will die
from the disease.5
- Most women with cervical cancer are
diagnosed before the age of 50; the median age is 48.3 However, older
women remain at risk. More than 20% of new cases are
diagnosed
in women over 65.
Cervical cancer
in
women younger than 20 is rare.5
- In the U.S., Hispanic women have the highest rate of cervical cancer, followed by African American, Caucasian, American Indian/Alaska Native, and Asian American/Pacific Islander women. Mortality rates are highest for African American women.6
- Between 1955 and 1992, the rate of
cervical cancer deaths in the U.S. declined
by nearly 70%. It continued declining more gradually to 2003. It has since stabilized. The
overall decline is mainly attributed to the increased use of the Pap test.5
- When
detected at its earliest stage, cervical cancer
has a 5-year relative survival rate of approximately 91%.
For regional disease, it is nearly 57%. If the cancer has spread to distant organs, 5-year survival drops to approximately 16%. In general, the
prognosis is affected by the extent
of disease at the time of diagnosis.3
- As of January 2009, there were approximately
250,000 cervical cancer survivors living in the
U.S.3
Risk Factors:
Human papilomavirus
- Virtually all (99.7%)4 cervical cancers are caused by persistent infection with a high-risk type of human papilomavirus (HPV). There are approximately 15 high-risk (oncogenic) types of HPV, with just two high-risk types, 16 and 18, responsible for about 70% of all cervical cancers.7
- Although HPV is most commonly spread from one person to another through sexual activity, it can also be spread without sex, by skin-to-skin contact with an area of the body infected with HPV.5
- More than half of all sexually active people will be infected with HPV at some point during their lives.7 However, the vast majority of HPV infections do not lead to cervical cancer. For cervical cancer to develop, a high-risk infection must also be persistent.
- Most HPV infections are transient. Up to 90%, including infections with high-risk types, resolve within 2 to 5 years. In young women, an average episode lasts from 8 to 13 months.8
- Aging is a risk factor for persistent infection. The rate of persistent high-risk infection for women older than age 55 is 50%, compared with a persistence rate of 20% in women younger than age 25.8
- While long-term infection is necessary for cervical cancer to develop, the vast majority of women with persistent high-risk infection do not develop cervical cancer.9
Other factors
Other factors have been found to increase the risk of developing cervical cancer, either by increasing the risk of HPV infection or by increasing the chances of developing cervical neoplasia following a high-risk infection. These other factors are as follows:
Sexual activity: The main risk factors for HPV infection through sexual activity are early onset of sexual activity; multiple sexual partners; high-risk sexual partners; 4 and failure to use a condom.
Weakened immune system: A
weakened immune system, such as that caused by HIV or by drugs used for suppressing immune response, places women at higher
risk for HPV infection and also for cervical cancer.5
Smoking: The risk of
squamous cell cervical cancer is increased for women who
smoke. Smoking
not only exposes the body to cancer-causing chemicals
but
also weakens the immune system. Smoking does not appear to be a risk factor for adenocarcinoma of the cervix.4
First full-term pregnancy
at a young age: A first full-term pregnancy
in women younger than 17 years old nearly
doubles the risk of developing cervical cancer
later in life, as compared with women
who had their
first full-term pregnancy at 25 years and older.5
Multiple full-term pregnancies: Women
with 3 or more
full-term pregnancies have an increased risk
of developing cervical cancer. Studies have pointed
to hormonal changes or weaker immune systems
during pregnancy as possibly allowing for HPV infection
and cancer growth.5
Family history
of cervical cancer: A women with a mother
or sister with cervical cancer has 2 to 3
times the risk of women without this family history.5
Oral contraceptives: The long-term use (5 or more years) of oral contraceptives has been shown to increase the risk of developing cervical cancer. A collaborative analysis of data from 24 epidemiological studies found that risk increases with duration and declines after use ceases. After 10 or more years of cessation, risk appears to return to that of normal.10 Clinicians are encouraged to discuss with their patients whether the benefits of fertility management outweigh the potential risks.
Diet and weight: Some
studies have shown that diets low in fruits and vegetables,
as well as being overweight,
may place women at increased
risk for developing cervical
cancer.5
Chlamydia infection: Some
studies have found a higher risk of cervical
cancer in women with past or current chlamydia
infections.5
Diethylstilbestrol (DES):DES
may increase the risk of a rare form of cervical
cancer in women whose mothers took DES when pregnant.
About 1 case of this rare form
occurs in every 1,000 DES daughters.5 (DES was given
to some pregnant women in the United States from
1940 to 1971.)
Risk Reduction:
- Women
have a choice between two FDA-approved vaccines (brand
names, Gardasil and Cervarix). Gardasil
protects against infection by HPV types 6, 11, 16 and 18 and Cervarix protects against types 16 and 18.
- Vaccination is not a substitute for screening
with Pap tests. Even in women who have been vaccinated,
cervical cancer is still possible. Nearly all cervical
cancer can be prevented with routine screening
and by limiting exposure to risk
factors.
Screening Guidelines:
There are minor differences in the U.S. screening guidelines for women with average
risk. The following table compares the current (2012) recommendations of two different groups: the U.S. Preventive Services Task Force (USPSTF) and a multidisciplinary partnership among the American Cancer Society/American Society for Colposcopy and Cervical Pathology/American Society for Clinical Pathology (ACS/ASCCP/ASCP).5, 11
Comparison
of ACS/ASCCP/ASCP and USPSTF
Screening Guidelines |
| |
ACS/ASCCP/ASCP |
USPSTF |
Recommendations apply to both conventional and liquid-based cytology. |
| When to Start |
Age 21 |
Age 21 |
| Intervals |
Ages 21-29:
Cytology alone every 3 years
Ages 30-65:
HPV and cytology “co-testing” every 5 years is preferred
OR
Cytology alone every 3 years is acceptable |
Ages 21-29 years:
Cytology alone every 3 years
Ages 30-65:
HPV and cytology “co-testing” every 5 years for women who want to extend their screening interval
OR
Cytology alone every 3 years |
| When to Stop |
Women older than age 65following adequate negative prior screening
(Women with a history of CIN2 or a more severe diagnosis should continue routine screening for at least 20 years after diagnosis ) |
Women older than age 65 who have had adequate negative prior screening (as defined below) and who are not otherwise at high risk
(Adequate negative prior screening is defined as 3 consecutive negative cytology results or 2 negative co-tests within 10 years before cessation of screening, with the most recent occurring in the past 5 years) |
Post Total
Hysterectomy |
Women who have had a total hysterectomy (with removal of the cervix) should not be screened unless there is a history of CIN2 or more severe diagnosis in the past 20 years, or a history of cervical cancer ever |
Women who have had a total hysterectomy (with removal of the cervix) should not be screened unless there is a history of high-grade precancer or cervical cancer |
For additional information
on cervical cancer screening and diagnosis, please
visit:
For information
on cancer screening services for medically underserved
women:
Breast and cervical cancer screening services are
available to medically underserved women living in
the United States through the National
Breast and Cervical Cancer Early Detection Program (NBCCEDP).
This national program is sponsored by the Centers
for Disease Control and Prevention (CDC) and
provides access to free or low-cost screening for
eligible women.
In California, the Every Woman Counts (EWC) program assists low income, uninsured, underserved women in obtaining high quality breast and cervical cancer screening and follow-up services. The program is administered by California Department of Health Care Services. EWC receives funding from the Centers for Disease Control and Prevention (CDC), National Breast and Cervical Cancer Early Detection Program (NBCCEDP), Proposition 99, one cent of a two-cent tax on tobacco products (mandated by the California Breast Cancer Act of 1993), and general funds.
Women who would like to find out if they qualify
for the program may call 1-800-511-2300 Monday -
Friday,
from 8:30 AM to 5 PM. The EWC representative for your area may know
of other low-cost screening programs that might be
available to you. Regional Contractors are also your
link to support groups, advocacy groups and the latest
information on what's happening in your community.
References:
2 National Cancer Institute (NCI).
(2012). Cancer advances in focus: cervical cancer. Accessed Aug.
14, 2012, from http://www.cancer.gov/cancertopics/factsheet/cancer-advances-in-focus/cervical
3Surveillance Epidemiological
and End Results (SEER). (2012). SEER
stat fact sheets: cervix uteri. Accessed
Jul. 16, 2012, from http://seer.cancer.gov/statfacts/html/cervix.html
4Frumovitz, M. (2011, Sep.). Invasive cervical cancer: Epidemiology, risk factors, clinical manifestations, and diagnosis. Accessed Jul. 30, 2012 from http://www.uptodate.com/contents/invasive-cervical-cancer-epidemiology-risk-factors-clinical-manifestations-and-diagnosis?source=search_result&search=cervical+cancer&selectedTitle=1~150
5American Cancer Society (ACS).
(2012). Cervical
cancer: detailed guide. Accessed Jul.
17, 2012, from http://www.cancer.org/Cancer/CervicalCancer/DetailedGuide/index
6Centers for Disease Control and Prevention (CDC). (2012). Cervical cancer rates by race ethnicity. Accessed Jul. 24, 2012, from http://www.cdc.gov/cancer/cervical/statistics/race.htm
7National Cancer Institute (NCI). (2012). Fact sheet: HPV and cancer. Accessed Jul. 30, 2012, from http://www.cancer.gov/cancertopics/factsheet/Risk/HPV
8Holschneider, M. (2012, Jun.). Cervical intraepithelial neoplasia: Definition, incidence, and pathogenesis. Accessed Aug. 5, 2012 from http://www.uptodate.com/contents/cervical-intraepithelial-neoplasia-definition-incidence-and-pathogenesis
9Hariri, S., Dunne, E., Saraiya, M., et al. (2011). Manual for the surveillance of vaccine-preventable diseases (5th ed.). Accessed Aug. 1, 2012, from http://www.cdc.gov/vaccines/pubs/surv-manual/chpt05-hpv.html
10Appleby P., Beral V., Berrington de González, A., et al. (2007). Cervical cancer and hormonal contraceptives: collaborative reanalysis of individual data for 16,573 women with cervical cancer and 35,509 women without cervical cancer from 24 epidemiological studies. Lancet, 370 (9599):1609-21.
11USPSTF. (2012). Screening for cervical cancer. Accessed Jul. 30, 2012, from http://www.uspreventiveservicestaskforce.org/uspstf11/cervcancer/cervcancerrs.htm
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Updated: August 15, 2012
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