A Trial of Two Electrosurgical Conizations: Histopathological Analysis of Excision Margins

Oswaldo Cruz Foundation

Status and phase: Completed; Phase 3

Conditions: Cervical Intraepithelial Neoplasia

Treatments: Procedure: LLETZ cone; Procedure: SWETZ

Study type: Interventional

Funder types: Other

Identifiers

NCT01929993

522/12

Details and patient eligibility

About

The purpose of this trial is to evaluate if Straight Wire Excision of the Transformation Zone (SWETZ) is superior to (Large Loop Excision of the Transformation Zone) LLETZ cone in reducing the incomplete excision of disease.

Full description

Cone biopsy is a surgical procedure which objectives the excision of endocervical pre-invasive disease located at transformation zone or glandular epithelium. Although cone biopsy is considered adequate for the treatment of endocervical dysplastic epithelium , using electrosurgery as opposed to the cold knife technique of cone biopsy has been criticized because of the perceived potential for incomplete excision of disease, thermal damage and surgical specimen fragmentation, which might increase the risk of missing early invasive cancer. Also, incomplete excision margin of disease exposes women to an increased risk of residual post-treatment disease.

The standard procedure, Large Loop Excision of the Transformation Zone (LLETZ-cone), is performed with a large loop electrode of 20-25 mm depth.

The experimental intervention is Straight Wire Excision of the Transformation Zone (SWETZ), a method of excision using a 1cm straight disposal of 0.20 wire to remove the endocervical transformation zone or glandular disease.

Both procedures were previously studied in another clinical trial(NCT00995020), but the histological analysis were inconclusive for many outcomes. SWETZ were superior to LLETZ cone to acquire complete excision of disease, with no statistical significance, probably due to the small sample size.

This study objectives a better histological analyses of the surgical specimens related to incomplete excision, thermal damage and fragmentation.

Enrollment: 164 patients

Sex: Female

Volunteers: No Healthy Volunteers

Inclusion criteria

• Patients were eligible if the colposcopist decided that a cone biopsy was indicated.

• Common indications for a cone biopsy included:

  • High-grade Squamous Intraepithelial Lesion in a type 3 transformation zone,
  • suspicion of micro-invasive or invasive carcinoma and
  • suspicion of glandular disease.

Exclusion criteria

• Patients were excluded if pregnancy, coagulation disorders and cervicitis were present or if they refused to participate in the study.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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164 participants in 2 patient groups

SWETZ

Experimental group

Description:

Straight wire excision of transformation zone is an electrosurgical conization method, which uses a straight wire electrode.

Treatment:

Procedure: SWETZ

LLETZ cone

Active Comparator group

Description:

LLETZ cone is a electrosurgical conization method, which is performed with a large loop electrode of 20 mm depth.

Treatment:

Procedure: LLETZ cone