Preclinical cancer of the cervix: diagnostic pitfalls.

This paper outlines the pitfalls encountered in the diagnosis of 127 preclinical cancers of the cervix. Each patient had cervical cytology, colposcopy, and histology performed within the same institution. Early stromal invasion was diagnosed in 55 patients and occult invasion was diagnosed in 72 patients. For preclinical cancers as a group, the possibility of invasive carcinoma was predicted cytologically in 36% and suspected colposcopically in 41%. However, in over 85% of patients the abnormal transformation zone (TZ) extended into or was totally confined within the endocervical canal and could not be adequately evaluated with the colposcope. A feature of this study was the high incidence of incomplete excision of abnormal tissue by cone biopsy and a high incidence of residual disease at hysterectomy. Cone biopsy was necessary to accurately assess the maximum depth and extent of invasion prior to definitive therapy whenever invasion was suspected colposcopically or on target biopsy. In 10 of 16 such patients, the cone biopsy demonstrated occult invasion. Colposcopy and directed target biopsy alone was adequate for the diagnosis of frank invasive cancer in 22 of the 72 patients in the occult invasion group, enabling definitive therapy to be undertaken without further delay.