Efficacy Study of Diathermy Cone Biopsy for the Treatment of Cervical Intraepithelial Lesion

A Study of Two Cone Biopsy Techniques For Women With Cervical Pre-Invasive Disease. LLETZ Cone and SWETZ.

The purpose of this trial is to determine whether SWETZ (Straight Wire Excision of Transformation Zone) is a superior alternative to LLETZ cone (Large Loop Excision of Transformation Zone cone biopsy) in the management of pre-invasive endocervical disease. SWETZ is a new cone biopsy procedure performed with a straight wire electrode and it will be compared to LLETZ cone, which is performed with a large loop electrode.

The treatment of precancerous lesions hinges on the destruction, or more commonly, the excision of the cervical transformation zone . When the transformation zone contains squamous precancer and is completely ectocervical and therefore full visible, excision or destruction is an effective and relatively straightforward therapeutic entity. However in a small proportion of women a cone biopsy is necessary. A cone biopsy often requires the excision of 20-30 mms of endocervical canal. Interventions. The standard procedure, LLETZ - cone (Large Loop Excision of Transformation Zone cone biopsy), is performed with a large loop electrode of 20-25 mm depth. The activated loop was applied to the cervix outside the lateral margin of transformation zone and brought slowly to the controlateral margin with the objective to acquire 20-25 mm up the canal. The experimental intervention is SWETZ (Straight Wire Excision of Transformation Zone), a method of excision using a 1cm straight disposal of 0.20 wire to remove the endocervical transformation zone or glandular disease. The activated wire was used as a knife, fashioning a cone with desired dimensions. This technique may be able to excise the endocervical transformation zone with a lower rate of morbidity and incomplete excision rate than LLETZ cone biopsy. The hypothesis to be tested in this trial is that SWETZ is superior to LLETZ cone in the management of endocervical pre-invasive disease.

Cone biopsy, Conization, Loop electrosurgical excisional procedures, Large Loop Excision of Transformation Zone, Needle Excision of Transformation Zone, Straight Wire Excision of Transformation Zone, Electrosurgery

The intervention administered in this arm is the straight wire excision of the transformation zone, a electrosurgical method to perform a cone biopsy using a 1 cm straight wire of 0.20 mm wire. The activated wire is used in much the same way as a cold knife or laser beam fashioning the surgical specimen to achieve two centimeters cm at cervical canal..

The intervention administered in this arm is the large loop excision of transformation zone as a cone biopsy, performed using a large loop electrode of 2 cm depth, applied to the cervix to achieving two centimeters at cervical canal .

Straight wire excision of transformation zone is a electrosurgical conization method,which uses a straight wire electrode as a knife to remove the dysplastic epithelium of the cervix.

LLETZ cone is a electrosurgical conization method, which is performed with a large loop electrode of 20-25 mm depth. The loop is applied to the cervix outside the lateral margin of TZ and brought slowly to the controlateral TZ margin.

Primary outcome is the number of participants with incomplete excision of dysplasia at the endocervical excision margin as recognized histologically.

Inclusion Criteria: Incompletely visible transformation zone in women with High grade Squamous Intraepithelial Lesion (HSIL) Suspicion of microinvasive carcinoma or occult invasive carcinoma Suspicion of glandular disease Exclusion Criteria: Pregnancy Coagulation disorders Cervicitis were present Refusal to participate in the study

Camargo MJ, Russomano FB, Tristao MA, Huf G, Prendiville W. Large loop versus straight-wire excision of the transformation zone for treatment of cervical intraepithelial neoplasia: a randomised controlled trial of electrosurgical techniques. BJOG. 2015 Mar;122(4):552-7. doi: 10.1111/1471-0528.13200. Epub 2014 Dec 17.