Thursday 20 September 2012
Cone biopsy of the uterine cervix
Definition: Conization of the cervix is a common treatment for dysplasia following abnormal results from a pap smear.
Diagnostic conization is indicated in the following situations:
Finding of epithelial cell abnormalities, in particular high-grade squamous intraepithelial lesions (HSIL) or low-grade squamous intraepithelial lesions (LSIL) in the absence of gross or colposcopic lesions of the cervix
Unsatisfactory colposcopy, defined as the examiner inability to view the entire transformation zone, including the squamocolumnar junction, in women with epithelial cell abnormalities
Uncertainty regarding the presence or absence of microinvasion or invasion following the diagnosis of CIN by directed biopsy
Finding of CIN or microinvasive cancer in endocervical curetting
Cytologic or histologic evidence of premalignant or malignant glandular epithelium
Cytologic diagnosis inconsistent with histologic diagnosis based on directed biopsy
Therapeutic conization is currently the preferred modality to treat CIN grades 2 and 3. All described approaches (cold-knife, laser, and LEEP conizations) are equally effective, as found by Mitchell and colleagues.
Historically, carcinoma-in-situ (CIN grade 3 - CIN3), the first identified intraepithelial neoplasia, was treated with hysterectomy. During the last quarter of the 20th century, several large published series had proved the effectiveness of the more conservative conization. Kolstad and Klem (1976) reported 1,122 patients with carcinoma-in-situ treated with conization with a recurrence rate of 2.3% and unexpected discovery of small invasive carcinomas in 0.9%. Bjerre et al reported treatment failure in 7% of their patients who received therapeutic conization.
Controversies exist as to the necessity of removing the entire endocervical canal, including the internal os, in all cases. This approach, recommended by at least 2 studies, may increase the risk of cervical incompetence in women who desire posttreatment pregnancy. It is the authors’ belief that it is possible to determine the probability of high endocervical involvement fairly accurately by performing endocervical curettage or by obtaining cytology with an endocervical brush. If these tests are negative for CIN or glandular atypia, and if the patient wishes to preserve her childbearing potential, we preserve the cranial extremity of the endocervical canal.
In addition to conization, CIN also can be treated by hysterectomy or by other destructive methods, such as cryotherapy, laser vaporization conization, or radical electrocoagulation.
The choice between hysterectomy and conization usually is based on the grade and extent of the disease, the patient旧 age, the desire for childbearing, and the history of recurrence after conservative management. Since destructive methods such as cryotherapy yield no specimen for histologic studies, their use should be limited to those women in whom an accurate preoperative diagnosis has been established by directed biopsies.
Cervical conization (CPT codes 57520 (Cold Knife) and 57522 (Loop Excision)) refers to a biopsy of the cervix in which a cone-shaped sample of tissue is removed from the mucous membrane. Conization may be used either for diagnostic purposes, or for therapeutic purposes to remove pre-cancerous cells.
cold knife conization (CKC).
- Usually outpatient.
loop electrical excision procedure (LEEP).
- Usually outpatient, occasionally inpatient.
Side effects of the treatment may include cervical stenosis with a resulting severe endometriosis. This procedure may increase the risk of incompetent cervix.
Cone-biopsy histology report, 1976. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC475997/?page=1