Bayrle W
Geburtshilfe Frauenheilkd. 1977 Oct;37(10):864-8.
In order to obtain a resonable approach to the rate of false negative findings in gynecologic cytology, all cases available to the authors for analysis with cervical carcinoma, carcinoma in situ and dysplasia during 1971 to 1973 were examined for any previous history of negative cytologic findings during the years preceding the detection of these pathologic conditions. It was found that negative results had been obtained in 11% of the patients suffering from cervical carcinoma, whereas the corresponding percentage figure was 18% negative results in carcinoma in situ patients. However, in about half of the cases, repetition of the smear had been recommended. Among the possible causes of false negative cytologic findings, the laboratory error (screening and evaluation) is the only one which can be accurately determined; in the present analysis, one-third of the false findings were found to be due to laboratory error. It is probable that the majority of the other false negative cytologic findings are mainly due to errors in sampling. As a matter of fact, rapidly growing carcinomas and carcinomas in situ are probably rare.