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The number of patients with cervical intraepithelial(CIN) has been increasing progressively in recent years. Conservative management for women with CIN, especially for those patients with high grade cervical dysplasia, has become more important, because most of these cases occur during the reproductive age and in those who have not completed their families. The management of cervical intraepithelial neoplasia by ablative therapy such as: cryotherapy, knife conization, laser vaporization or conization is generally accepted as a safe therapeutic method. Recently, however, a new therapeutic modality using wire loop electrodes has been applied to precancerous lesions of the cervix.
A French urologist, Cartier, the “father” of the e1ectrosurgical loop, created the loop equipment in 1950. He first proposed the technique to perform cervical excision for precancer lesions in 1981 (Cartier et al, Proceedings of the International Federation for Cervical Pathology and Colposcopy, London,1980). Early loop procedures were performed under general anesthesia using a high power setting that induced tissue damage and a marked thermal effect. Since 1984 (Cartier), a new design of the loop using a lower power setting has been proposed that offers the patient a low bleeding risk, loca1 anesthesia and a shorter procedure time. From that time on, prodigious advances have been made in the realm of loop techniques, with a series of papers reporting on the management of “Loop Excision 0f Transformation Zone”(LETZ). The use of LEEP has been rapidly integrated into the management of cervical intraepithelial neoplasia. When comparing LEEP conization with cold-knife conization, there were numerous prospective studies on cervical dysplasia, and both of the treatment modalities were recognized as equally efficacious with respect to histological evaluation and disease recurrence (Mathevet et al. 1994; Gkadii et al. 1994; Naumann et al.1994).
Since April 1990,we have performed the loop electrosurgical excision procedure (LEEP) as a diagnostic and therapeutic procedure in one setting for cervical intraepithelial neoplasia. The LEEP was used usually as. a diagnostic and therapeutic procedure in one setting for these cervical intraepithelial neoplasms at our colposcopic clinic.
Patients with a colposcopically proven biopsy of cervical intraepithelial neoplasia were eligible for LEEP if they met following criteria: (1) The entire lesion on the cervix was seen. (2) Invasion of cervical stroma was excluded. (3) Patients were reliable for close
follow-up, especial in severely dysplastic cases. After correlation of the patient's cytological findings, colposcopic impression, and pathologic findings of a directed biopsy, a treatment recommendation was made.
Regarding LEEP equipment, the instrument used during LEEP is a rectangular, stainless steel wire, 0.2 mm in diameter, Loops ranging from 10 mm to 25 mm in width and 10 mm to 20 mm in depth were used. The size of the loop was chosen to ensure the excision of the whole lesion and transformation zone in one piece. We usually used a 2.0 cm large loop or a 1.5 cm diathermy straight wire 'to perform a cone excision, in a
one-pass application when possible. Ball electrodes with dimensions of 3 mm and 5 mm were also available. A generator, hand handles, and conductive adhesive return electrodes are also necessary equipment for the loop electrodes. Regarding LEEP generator, LEEP conization was performed using a Finesse II electrosurgieal generator (Utah Medical Products, Midvale, UT) in the cutting mode, with 60 W and blend 2 selection. A generator of Valleylab (Valleylab international, Electrosurgical Generator, Force 2, Colorado, U.S.A.) may also be used. The cutting and coagulating powers (for Valleylab) used for LEEP were 25 to 35 watts, and 2.5 to 3.5 units, respectively. A smoke filtration system and
non-conductive specula were also prepared.
Evaluation of the exocervical margins was done at the time of excision by LEEP. Endocervical curettage (ECC) was performed in all instances after LEEP to assess the higher endocervical status.
The LEEP was done as an outpatient procedure under local anesthesia accomplished by a superficial intracervical injection of 2% xylocaine plus a 1:100,000 solution of epinephrine. The injection amount was about 10 mL. The anesthetic was administered using an auto injector with a 23-25 gauge needle and 10 mL syringe. The area of anesthetic injection' was beyond the transformation zone and the lesion area. However, the LEEP conization was preferred on an inpatient basis with general anesthesia. The loop size used for conization was 20 x 15 mm or 20 x 20 mm. The smallest sized loop was usually used for endocervical excision or a cervically directed biopsy. All procedures were performed by experienced operators under colposcopic guidance. A repeat colposcopy was reevaluated immediately after the LEEP to record the margins status of cervix and the possibility of residual lesions.
Regarding the LEEP techniques, the objective surgical technique was remove the entire transformation zone with one pass of the loop, if possible, as a conization. The technique of LEEP went from right to left across the transformation zone and the target lesion. The excised margin of the cervix was approximately 5 mm outside the periphery of the transformation zone. The depth of the excised specimen was at least 5 mm. The loop was advanced slowly And the cutting time was
3-10 seconds. A slow continuous movement of the loop through the tissue provided the best results in term of minimal bleeding and good histological specimens. The operating temperature of the loop wire, was below 130 0C , otherwise the find wire would ruptured. A
T-bar (ARKMED Inc, Colorado, U.S.A.) was also used to provide a reference for the depth of the excision. Gauze was used to pack the cervical wound for three days.
One week after LEEP, the cervical wound was rechecked at clinic. After about two months of healing, we reevaluated the cervix with a Papanicolaou smear and by colposcopy. Patients were examined in the colposcopy clinic at
four-month intervals after the complete treatment. Biopsy was carried out colposcopically at any time if any suspicious residual lesion was noted during follow-up.
Regarding the thermal damage, some authors have shown that extensive thermal artifacts are identified in around 9.2% to 31% of specimens obtained with LEEP conization Mathevet et al. 1994; Girardi et al. 1994;lessing et al. 1994; Montz et al. 1993), In which the LEEP resection leads to coagulation of the tissue, precluding histological interpretation.
However, the occurrence of thermal damage is dependent on the surgeon's experience and skill. Haggish et al. (1992) and Paraskevaidis et al. (1994) have shown that the coagulation artifacts caused by the LEEP procedure not interfere with the histopathologic interpretation of the cone specimens, as supported by our reports.
One of the disadvantages of LEEP conization demonstrated by our data is the high frequency of tissue transection, which precluded pathologic interpretation of the stromal status. In large lesions, multiple applications were often inevitable. A significant problem with orientation of the specimen was noted when
multiple-pass applications were required to remove the transformation zone. The depth of invasion and the lateral extent of the tumor may not be accurately measured in cervical cancer if the focus of invasion is transected. Shafi et al. (1992) and Messing et al. (1994) had reported that multiple passes of LEEP might transect the cervical lesions, as presented in our study, and create problems with misorientation of histological interpretation.
With regard to the endocervical depth of conization, assessment of the endocervical canal and its involvement by abnormal epithelium is one of the most difficult areas of diagnosis. Full examination of the canal should serve both to determine the upper limit of the lesion and to exclude invasive disease within the canal. Evaluation of an occult lesion high in the endocervical canal requires an adequate endocervical depth on cone specimens. Our data, in agreement with previous studies (Mathevet et al. 1994), showed that LEEP removes significantly less of the endocervix than cold knife conization. It is possible that the use of LEEP may not entirely encompass the endocervical lesion and may not have an accurate diagnosis.
In conclusion, excision of the transformation zone using LEEP has several advantages including the following: (1) It offers patients less bleeding, less procedure time and local anesthesia. (2) The limits of the transformation zone may be clearly defined and the margins of excision may be assessed exactly. (3) Microinvasive disease may be ruled out with confidence. (4) The histological diagnosis is reconfirmed. However, we should keep in mind that multiple slices of LEEP application should be avoided. We suggest that in the treatment for cervical intraepithelial neoplasia, LEEP is an effective modality that can excise cervical lesions and transformation zones completely under colposcopy without retaining cervical tissue to fit a cervical suture. It is particularly suitable for treating younger women who have not yet completed their families.
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