NCT05132114: LLETZ-IOLI

Large Loop Excision of the Transformation Zone (LLETZ) With vs Without IntraOperative Application of Lugol's Iodine

Completed NA Last updated 14 April 2026

What this trial tests

NA trial testing Lugol's iodine test in Cervical Dysplasia in 230 participants. Completed in 16 October 2025.

Timeline

17 January 2022

Primary endpoint
25 September 2025

16 October 2025

Quick facts

Lead sponsor	Ruhr University of Bochum
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	single
Primary purpose	treatment
Enrollment	230
Start date	17 January 2022
Primary completion	25 September 2025
Estimated completion	16 October 2025
Sites	1 location across Germany

Drugs / interventions tested

• Lugol's iodine test

Conditions studied

• Cervical Dysplasia — all drugs for Cervical Dysplasia →

Sponsor

Ruhr University of Bochum

Who can join

18 and older, female only, with Cervical Dysplasia. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Cervical cancer is one of the most common cancers in women and one of the leading causes of death in women worldwide. Pre-cancerous lesions (dysplasias) are detected by the gynecologist's preventive smear test and can thus contribute to a 100% chance of cure if they are clarified by a colposcopic examination as part of the dysplasia consultation and, if necessary, surgically removed. Conization (= surgical removal of a cone of tissue from the cervix) is the method of choice for removing the diseased tissue. LLETZ conization (Large Loop Excision of the Transformation Zone) is the worldwide standard surgical procedure for conization. There is risk of local persistence of the precancerous lesion if the cervical dysplasia is not completely removed. To minimize this, the iodine test can be used. Here, a 5% iodine solution (so-called Lugol's solution) is dabbed onto the cervix uteri, resulting in an intense and characteristic brown staining of the healthy cervical epithelium. Sites without staining are termed iodine negative and may contain dysplastic cells. The strength of iodine testing lies in its high specificity, i.e., the reliable ability to exclude false-positive results. The purpose of intraoperative iodine staining is to select the resection line with a high degree of certainty in healthy (i.e., iodine-positive) tissue in order to reduce the rate of cervical dysplasia that is not completely removed (so-called non-in-sano resection, or R1 resection). Systematic survey data from the dysplasia units certified in Germany on the question of the use of intraoperative iodine testing in Germany are lacking, as is the literature as a whole. For example, the current S3 guideline of the German Society of Gynecology and Obstetrics on the diagnosis and treatment of cervical dysplasia (as of March 2020) names intraoperative iodine testing only as a possible option for performing LLETZ.

In this prospective, randomized study, the investigators aim to answer the question whether LLETZ performed with the help of an iodine test with selection of the resection line in the iodine-positive area leads to a lower rate of R1 resections compared to the standard LLETZ without iodine test.

Publications & conference data

No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.