Correlation between colposcopically directed biopsy and cervical loop excision.

Colposcopy is standard for diagnosis of cervical cancer precursors, but the development of diathermy loop electrodes for excision of the cervical transformation zone offers a technique for validation. Loop excision of the transformation zone was performed for 47 consecutive women with dysplasia in colposcopically directed biopsies using 20 x 8-mm electrodes. Specimens were marked for orientation and serially sectioned. All pathology material was reviewed. Although 28% of women had disappearance of dysplasia at the biopsy site, only 9% had no dysplasia in the transformation zone. Half of the women with CIN 1 on directed biopsy had high-grade lesions found in loop excision specimens. Significant discrepancies may be found between the results of colposcopically directed biopsy and loop excision.