Cervical conization (also known as cone biopsy) refers to the excision of a cone-shaped portion of the cervix surrounding the endocervical canal and including the entire transformation zone. Excisional treatment can be performed using a scalpel, laser, or electrosurgery (ie, loop electrosurgical excision procedure [LEEP], also called large loop excision of the transformation zone [LLETZ]). There is no evidence that one technique is significantly better than another.
Since squamous lesions typically arise at the transformation zone, the procedure usually enables the pathologist to study an intraepithelial or superficially invasive lesion in its entirety. However, conization does not always remove the entire transformation zone or lesion. Excision is less likely to be complete in certain situations, such as pregnancy, or when the transformation zone is large or high in the endocervical canal, or when the lesion extends onto the vaginal fornices or very deep into the cervical stroma.
Ablative procedures, which are usually done with cryosurgery or with the laser, are an alternative to conization. However, no pathologic specimen is obtained since the cervical tissue is destroyed. These procedures are purely therapeutic and not of diagnostic value. They are appropriate for selected patients with previously well characterized lesions histologically and colposcopically, in whom invasive cancer has been excluded.