Can You Trust Your Pap Smear?
Since its introduction in 1939, the Pap smear has led to a 75% drop in cervical cancer deaths in the US. Yet, instead of lauding this achievement- undisputedly one of the greatest medical innovations of the 20th century- what women hear instead are the rare reports of tragic errors or oversights in diagnosis which led to unacceptable outcomes in the affected patients. This creates confusion and fear in the patients who can benefit most from Pap smears, and who should be able to trust and rely upon the results. Dr. Donnica Moore discusses what a Pap smear is; who should have one and how often; what the new cervical screening technologies are; and whether you should request them either instead of or in addition to your annual Pap.
In 1997, a Gallup survey commissioned by the College of American Pathologists found that although nearly 9 out of 10 women surveyed knew they should have a Pap test every year, nearly 4 out of 10 of these women failed to do so in the previous year. Why? One in 4 of these women said they didn't have their Pap smears because they "didn't have the time". Other reasons given include the belief that they were too old, felt embarrassed, were afraid of the results, thought they didn't need it, or thought it was "too expensive". While these considerations are important for women, they should be minor compared to taking a simple, painless test which has saved millions of lives- one of which could be yours.
The figures for minority women are more concerning: according to the US Department of Health and Human Services (HHS), one out of every 3 Hispanic women reported that they did not get a Pap test in the preceding three years, compared with one in every 4 American women in general. Of even more concern, the rate of death for African American women from cervical cancer is nearly twice that of Caucasian women.
If you are overdue for your Pap smear, take a break from reading this article
right now and call your doctor to schedule it-- then come back to finish
reading this article!
What is a Pap Smear and How is it Done?
A Pap smear is a simple test done during a woman's internal (pelvic) exam. Her health care provider performs a vaginal exam with a speculum (a tool to visualize the cervix), and uses a cotton swab, small brush, or small wooden spatula to painlessly scrape a cell sample from the inside and then the outside of the cervix (the tip of the uterus). If you can feel anything, it feels most like rubbing the back of your hand with your finger. These cells are then spread on a slide, sprayed with a fixative, and sent to a lab where the slides are screened for abnormalities by a cytotechnologist (trained technician) and reviewed by a cytopathologist (medical doctor) if necessary. The results are then communicated back to the health care provider who is responsible for communicating the results to the patient.
Who Needs a Pap Smear and When?
While most doctors still recommend that all women over the age of 18 have
annual Pap smears with their pelvic exams, the American College of Obstetricians
and Gynecologists (ACOG) has issued new, evidence-based practice guidelines
regarding Pap smear frequency (7/03). ACOG notes that while some women need
more frequent screening, an increasing number of women no longer need annual
cervical cancer screening. They have also noted that cervical cancer screening
can often begin later than previously recommended. This is somewhat misleading,
however, because most women associate their annual Pap smear with their annual
internal, pelvic exam. ACOG cautions that annual pelvic examinations are still
advised for all women over age 21.
ACOG's new recommendations are based in part on newly available screening tests
as well as a new appreciation for the pathology and evolution of cervical cancer.
To summarize ACOG's new recommendations:
Changes in Screening Frequency
First Pap test: Women should have their first Pap test (a screening of cervical
cells) approximately 3 years after first sexual intercourse or by age 21, whichever
Women up to age 30: Women this age should undergo annual Pap testing since
women under age 30 have a higher likelihood than older women of acquiring high-risk
types of HPV that may cause precancerous cervical changes.
Women age 30 and older: ACOG says there are two acceptable screening options
for women in this age group. Under either option, women may not need annual
- Testing using Pap smears alone. If a woman age 30 or older has negative
results on three consecutive annual Pap smears, she may then have her repeat
Pap smears every 2-3 years.
- Testing using a combined Pap test with an FDA-approved test for high-risk
types of HPV: Using this new option, women receive both a Pap test and a genetic
test that looks for certain high-risk types of the human papillomavirus (HPV),
the virus known to cause 99% of cervical cancers (HPV DNA test). If women
test negative on both tests, they may have repeat testing with the combined
tests every 3 years. If only one of the tests is negative, however, more frequent
screening will be necessary.
Of course, there are exceptions to all guidelines, and these are no exception!
More frequent cervical screening may be required for higher-risk women who are
infected with HIV, are immunosuppressed (such as those receiving kidney transplants
or who take immunosuppressant medication), were exposed to DES in utero, or
were previously diagnosed with cervical cancer.
Women who have had a hysterectomy with removal of the cervix for benign reasons
and with no history of abnormal or cancerous cell growth may discontinue routine
Pap smear testing.
Women who have had such a hysterectomy but who have a history of abnormal
cell growth (classified as CIN 2 or 3) should be screened annually until they
have three consecutive, negative vaginal cytology tests; then they can discontinue
When to Discontinue Screening -- Physicians can determine on an individual
basis when a woman over 65 can stop having cervical cancer screening, based
on such factors as her medical and sexual history and the physician's ability
to monitor the patient in the future. Unfortunately, there are limited studies
of women in this age group making it difficult to set an across-the-board upper
age limit for cervical cancer screening.
Annual Exams Continue: Regardless of the frequency of cervical cancer screening,
annual gynecologic examinations, including pelvic exams, are still recommended.
Where to Go for a Pap Smear
Your gynecologist or other primary care physician (internist or family doctor),
nurse practitioner or physician assistant can perform your Pap smear. If you
do not have access to a regular physician or need financial assistance, you
can also obtain a Pap smear at most student health clinics or Planned Parenthood
offices. The YWCA is
also running an excellent program called "Encore Plus" to help women obtain
free or low cost breast and cervical cancer screening.
After having your Pap smear, always follow up and ASK for your results. Don't assume you will be contacted if the test is abnormal or inconclusive.
Why Get a Pap Smear Regularly?
The Pap smear is the most important screening test to detect early evidence of cervical cancer. In addition, it can detect many other infections and cervical abnormalities. It is the most widely used cancer screening test in the world. Yet it is not perfect. The public's confidence in the Pap smear as such a precise tool for cancer screening has led many to false believe that if cancer is detected after a normal Pap smear, malpractice must have occurred.
Each year in the United States, approximately 16,000 women are diagnosed with
invasive cervical cancer and tragically, nearly 5,000 die annually of this disease.
I say "tragically" because many of these premature deaths could have been prevented:
of the 5,000 women per year who die of cervical cancer, most had not even had
a Pap smear in over 5 years! Rates of decline in cervical cancer since broad
based PAP screening are substantial in the US: prior to the Pap smear, the cervical
cancer incidence rate in the US was 44 cases per 100,000 women; now it is 7
cases per 100,000 women. Globally, however, fewer than 5% of women have had
a Pap smear and more than 80% of cervical cancer cases worldwide occur in developing
What is Cervical Cancer?
Cervical cancer is a cancer of the cervix, or outer entrance to the uterus (womb). It develops slowly, long after abnormal or "dysplastic" changes could be detected in the cervical cells. Worldwide, cervical cancer affects 450,000 women per year; it is the third most common cancer to affect women in the world (after skin cancer and breast cancer).
Cervical cancer is one of the few cancers where a probable cause has been identified: recent medical studies have confirmed that the human papilloma virus (HPV) is associated with most cervical cancer. HPV is also the virus that causes genital warts. Because this virus is sexually transmitted, cervical cancer can be considered a sexually transmitted disease as well as a cancer; there are virgins who also get cervical cancer, however.
A recent study from Sweden demonstrates that genetics may have a much larger role in cervical cancer etiology than previously suspected.
Risk factors for cervical cancer:
History of HPV infection
History of venereal warts, herpes simplex or any STD
History of previous abnormal pap smears
Smoking, or abusing other substances, including alcohol
Having a mother who took the drug DES (diethylstilbestrol) during pregnancy to prevent miscarriage (1940-1970)
Having impaired immune system function
Having had more than 2 male sexual partners in the past without condom use (or having had a partner with a history of more than 2 sexual partners)
Having a male sexual partner who has had a sexual partner with cervical cancer
Family history of cervical cancer
Lower socioeconomic status
History of lower genital tract dysplasia or cancer
Are You at Risk for Cervical Cancer?
HPV is one of the most common sexually transmitted infections in the US, and a majority of sexually active women are exposed to it at some point in their lives. Only a small percent of women with HPV will develop cervical cancer, however, in most women immunity will control the virus, of which there are now known to be 70 different strains. Of these, only 13 strains are associated with cervical cancer. Only women with persistent HPV infection with one of those strains are at increased risk of developing cervical cancer. Ask your doctor if you need to be tested for this virus.
One in 10 pap smears will have some abnormality, so don't panic if you get a call from your doctor's office asking you to return (but do go!). Most of the time these are due to collection errors, changes associated with inflammation or a low-grade lesion. There are basically four stages of cervical disease as reported by the Pap smear:
1. Healthy-although inflammation or infection may be present, no atypical cervical cells are noted. If you have inflammation or infection, your doctor may recommend treatment and then repeat the Pap smear in 3-6 months.
2. Low-grade disease - which can include "ASCUS", "atypical squamous cells of undetermined significance". If a Pap smear shows questionable or low-grade changes, your doctor may recommend repeating your Pap in three to six months. But if you've had a previous abnormal pap or a known sexually transmitted disease including HPV, s/he may want recommend further testing, including in-office examination with a special magnifier called a colposcope. Using this and special dye, your doctor can perform one or more small cervical biopsies of the abnormal areas identified. This permits an accurate diagnosis and helps determine the extent of any precancerous changes.
3. Hi-grade disease - severe dysplasia or "carcinoma in situ" where abnormal cells are limited to the surface of the cervix; conservative treatment is usually effective.
4. Invasive cancer-where cellular abnormalities are found deep in the tissue of the cervix; hysterectomy is usually required.
The good news is that cervical cancer is preventable, treatable and curable
if detected in its earliest stages. Cervical cancer is also generally a very
slow growing cancer. When cervical cancer is detected at an early stage, the
five-year survival rate is 91%. For those patients whose cervical cancers are
not detected early, five compelling clinical studies this year support a new
treatment strategy anticipated to cut the death rate in half- the recommendation
is now to add chemotherapy to radiation after hysterectomy.