Page 44 - Screening for Cervical Cancer: Systematic Evidence Review
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Chapter III. Results
1990s) suggests that cancer outcomes are statistically comparable with intervals of three to five
years. Three years was recommended as a conservative estimate of appropriate interval.
Screening among Women Who Have Had a Hysterectomy
The 1996 USPSTF report is unequivocal: women who have undergone a hysterectomy
in which the cervix was removed do not benefit from Pap testing, unless it [the hysterectomy]
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was performed because of cervical cancer.(p.111) This opinion was based on recognition that
Pap testing in the absence of a cervix no longer constitutes screening for cervical cancer. In this
context the Pap test becomes screening for vaginal cancer, a yet more rare condition. Prior
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publications support this view. Nonetheless, a recent publication based on practice patterns at
the Marshfield Clinic (a 450-physician multi-specialty clinic in Wisconsin) suggests that more
than half of women who have had total hysterectomies for benign disease continue to receive
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screening at an average of one test every 3.5 years. This confirms the clinical opinion of
members of our group that the majority of women continue to receive screening even after
hysterectomy for benign disease.
Two additional studies documenting the low risk of cytologic abnormality after
hysterectomy have been published since the 1996 USPSTF recommendations. The first, among
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women age 50 and older, is a cross-sectional study with a nested case-control component.
They documented that identification of dysplasia and cancer was rare (1.6/1,000 tests) in this age
group, especially after hysterectomy (0.18/1,000). They also showed that, compared to matched
controls, women after hysterectomy were one tenth as likely as those with a cervix to have any
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Pap test diagnosis of abnormality. Likewise, Pearce and colleagues study of 6,265 women
(with 9,610 Pap tests) who had hysterectomies for benign disease found a total of 104 abnormal
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