One medical malpractice insurer, The Doctors Company, has an interesting article on medical malpractice claims concerning pap smears.
Here is a excerpt from the article that discusses the scope of the problem:
To put the potential magnitude of this problem in perspective, a College of American Pathologists (CAP) study of the five-year “look-back” at previous negative Pap smears following the diagnosis of HSIL/carcinoma found that 10 percent of prior smears were false negatives for SIL/carcinoma. If atypical squamous cells of undetermined significance (ASC-US) were included, 20 percent of prior smears were false negatives. In 1996, the American Cancer Society predicted 15,700 new cases of cervical cancer and 4,700 deaths. Published studies indicated that 60–75 percent of women dying from cervical cancer either never had a Pap smear or had not had one in the five years prior to diagnosis. Therefore, if one assumed that 40 percent of the predicted new cases of cervical carcinoma had a single Pap smear in the prior five years with a 20 percent false-negative rate, there was a potential for 1,256 new claims for failure to diagnose cervical carcinoma on a Pap smear in 1996 alone! [Footnotes omitted.]