False-negative cytology rates in patients in whom invasive cervical cancer subsequently developed.

The 3-year screening interval recommended by the American Cancer Society would appear to decrease the detection of premalignant and malignant disease. The authors have shown that 20% of study patients in whom subsequently invasive cervical cancer developed had at least 2 negative Papanicolaou smears within 3 years of the diagnosis of cancer. Moreover, the majority of false-negative results in the series could be attributed to sample error. The authors recommend yearly or at least biennial cervical cytologic screening.