CHAPTER 149 Loop Electrosurgical Excision Procedure for Treating Cervical Intraepithelial Neoplasia
A variety of techniques can be used to treat cervical intraepithelial neoplasia (CIN). The appropriateness of a particular technique to treat a particular lesion depends on a number of factors, including lesion size, location, and extension into the endocervical canal. Many clinicians now use the loop electrosurgical excision procedure (LEEP) to treat most women with biopsy-confirmed CIN 2 or CIN 3. With LEEP, thin wire loop electrodes are used to excise the entire cervical transformation zone. This procedure is referred to by a number of different names, including loop electrosurgical excision procedure (LEEP), large loop excision of the transformation zone (LLETZ), and loop excision. Many clinicians subdivide LEEP into two procedures: (1) routine LEEP, which is used to excise lesions confined to the exocervix (or visible portion of the cervix), and (2) LEEP conization, which is used when lesions extend into the endocervical canal. LEEP has a number of advantages over other treatment modalities for CIN, including the following:
The anatomy relevant to the LEEP is reviewed in detail in Chapter 137, Colposcopic Examination. As the procedure involves complete removal of the transformation zone, it is important to understand the anatomy of the cervix, including normal and abnormal appearances. In most circumstances, a colposcopy will be completed prior to the LEEP to define the anatomy of the cervix.
The following indications are based on the 2006 American Society for Colposcopy and Cervical Pathology (ASCCP) guidelines that are reproduced in Appendix K, Management Guidelines for Abnormal Cervical Cancer Screening Tests and Histologic Findings. Several options are given for treatment of most of these indications. This chapter presents the possible indications for the LEEP.
Figure 149-1 Electrosurgical units used for loop electrosurgical excision procedure (LEEP). A, Utah Medical electrosurgical unit. The smoke evacuator is included in the basic unit. B, CooperSurgical LEEP unit. C, Ellman Surgitron with handpiece, electrodes, antenna plate, and foot pedal.
(A, Courtesy of Utah Medical Products, Inc., Midvale, UT. B, Courtesy of CooperSurgical, Trumbull, CT. C, Courtesy of Ellman International, Hewlett, NY.)
Figure 149-2 Wire loop electrodes for loop electrosurgical excision procedure (LEEP). A, Loop electrodes come in a variety of sizes and shapes. B, Ellman electrodes. C, Utah Medical electrodes with an optional adjustable stop to limit depth (middle, green-handled loop). D, Fischer electrode, which removes more of a conical piece.
(A–C, Courtesy of The Medical Procedures Center, PC, John L. Pfenninger, MD.)
It is recommended that clinicians use only the shallow loop electrodes (i.e., either 0.8 or 1.0 cm deep) for routine LEEP. Larger electrodes can be used with large cervices or when lesions extend into the endocervical canal (e.g., LEEP conization). A variation is the Fischer electrode, which provides a true “cone” specimen.
Figure 149-3 Coated instruments to prevent electrical shocks. Vaginal sidewall retractors (arrow) are essential in many cases to avoid lacerating the vaginal walls. Three different vaginal speculums are on the left, each with a vented tube to attach to the smoke evacuator tubing.
It is imperative that the LEEP not be used to excise the TZ indiscriminately in women with atypical Papanicolaou (Pap) smears. The procedure should be reserved to treat advanced lesions as per the established indications, not just atypical Pap smears or CIN 1. CIN 1 has a high rate of regression and should usually be observed or treated with less invasive options. Cryotherapy is less expensive, has fewer complications, and has equal outcomes in properly selected patients (while at the same time removing less tissue) (see Chapter 138, Cryotherapy of the Cervix). Cold-knife conization is preferred when conization is being performed for a glandular abnormality.