Pap
Smear, Pelvic Exam, Breast ExamKnowing the facts about growth behavior
regarding cancer of the cervix helps in being proactive about cancer screening
with the yearly Pap smear. This test was introduced on a larger scale in the 1950's
and 1960's. It consists of two parts: a Pap smear and a bimanual pelvic exam.
With breast cancer being so frequent physicians have added a third part, namely
a breast exam, to rule out early breast cancer. This is good cancer prevention. The
Pap test (or Pap smear) is done in the "lithotomy
position" where the woman lies on her back and has her legs
supported in stir-ups. The cervix is visualized by the physician by entering a
metal or plastic "speculum"
into the vagina. The
speculum consists of two elongated blades that are spread apart so that the vaginal
walls are held apart thus enabling the physician to inspect the surface of the
cervix. The physician will then touch the surface of the cervix with a slim wooden
spatula and gently remove some of the surface cells of the cervix and smear them
onto a small rectangular glass slide. Another sample of cells is then taken with
a cotton swab from the cervical canal in order to screen for a hidden cancer that
might hide inside the cervix. Another smear is made of that either on the same
slide, if it is divided, or else on a second glass slide. The two smears are sent
to the clinical pathology lab for analysis. It might take several weeks before
the results come back (unless it is rushed in highly suspicious cases).
Here is the terminology that has been used and the one that should be used:
| Classification
of Pap smear | | Original
Pap smear: | WHO system: |
| (terms used in the past) | (terms
that should be used) | | class
I | normal |
| class II | atypical |
| class
III | mild dysplasia |
| moderate dysplasia |
| severe dysplasia |
| class IV | carcinoma
in situ | | class
V | invasive carcinoma |
In
the past there was another popular classification system used in the U.S., the
Bethesda system. However, the terminology was misleading in view of the world
wide accepted World Health Organization system depicted here as the same term
suddenly meant a class III cancer in the old Pap terminology. On the other hand,
there was not enough differentiation among the critical class III Pap group, which
simply was either called "low grade" or"high grade". Some
physicians still use the old Pap terminology, but add in class III the remark:
"with mild dysplasia"etc. In a trial published in the New
England Journal of Medicine 2007 where a Pap test was done alongside testing
for HPV (human papilloma virus), it turned out that the HPV testing was twice
as sensitive as the Pap test in picking up abnormalities. As HPV accounts for
most abnormal Pap tests in the "atypical cells" to the various degrees
of "dysplasia" (old class II and III classification), it is now possible
to triage these women differently as many of these women will not need to go on
for biopsy or colposcopy immediately. They will be sent to a gynecologist who
will do treatments according to the findings and history. This may involve repeat
testing in 3 to 4 months, cryotherapy with liquid nitrogen or colposcopy and biopsy
in the more suspicious lesions. Pap test screening (plus HPV testing) still has
to be done in younger women who have been vaccinated against HPV in high school
as the vaccine does not cover for all of the carcinogenic HPV types. The
second part of the Pap test is, as I indicated above, a bimanual examination.
With the patient still in the lithotomy position the physician will ask the woman
to relax her pelvic and abdominal muscles while he/she examines with two fingers
of the one gloved hand through the vagina and at the same time with the other
hand through the abdomen. The objective of this bimanual
examination is to determine the size and consistency of the cervix,
the uterus and both ovaries in rapid succession. The physician will also attempt
to feel pelvic lymph glands in the case of established cancer. Gynecologists also
always do a rectal examination at the end. This should be done to rule out any
cancer in this region or to detect any cancerous pelvic lymph glands or an abnormal
uterus that is bent backwards towards the rectum. Not many general practitioners
tend to do the rectal examination as it can be uncomfortable for the woman. The
bimanual pelvic examination done on at least a yearly basis is the only prevention
for ovarian cancer. Expressed more pointedly, it may be the only step between
prevention and death for a woman who develops ovarian cancer (see chapter on ovarian
cancer). If a lump of the ovary is detected by the Pap test (part
2, bimanual exam), the physician can refer her to a gynecologist and the ovary
can be removed. This woman in all likelihood will live (95% 5-year survival for
stage I cancer of the ovary). If it is deferred and the cancerous lump in the
ovary sheds cancer cells into the abdominal cavity, the window of opportunity
to save a life will have been lost (only 10% to 30% live for 5-years). Here
is a reference
text regarding Pap tests from the National Cancer Institute.
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