The diagnostic accuracy of combined colposcopy, cytology, and target biopsy of carcinoma in situ of the uterine cervix.

The results of cytology, colposcopy and target biopsy in 91 cases diagnosed by conization as uterine cervical carcinoma in situ and 39 cases diagnosed as microinvasive carcinoma were compared. Lesions limited to the ectocervix could be identified by colposcopy, and those identified as carcinoma in situ by cytology or target biopsy were all included in the group diagnosed as carcinoma in situ by conization. Among the 29 cases of carcinoma in situ limited to the ectocervix, 19 (66%) were similarly diagnosed by both cytology and target biopsy, allowing for us to avoid conization. For cases diagnosed as microinvasive carcinoma using target biopsy, conization must also be performed in order to determine the depth of invasion. Even in cases diagnosed as dysplasia or carcinoma in situ by target biopsy, when it is thought that the lesion may extend into the cervical canal or in cases where agreement with the cytological results is not found, conization is necessary.