Confocal Laser Endomicroscopy for Brain Tumors (CONVIVO)

The prognosis of glioblastoma patients highly depends on resection extent. Various strategies have been introduced to overcome the dilemma of intraoperative tumor identification.

In gastroenterology, confocal laser endomicroscopy (CLE) allows precise differentiation of tumor tissue from surrounding mucosa in various diseases. Combining high-definition white light endoscopy with CLE significantly increases sensitivity and specificity compared with the sole application of high-definition white light endoscopy.

CLE was recently introduced to neurosurgical applications. Although still in an early stage of clinical application, this technique has proven to be capable of differentiating various tumor entities in animal models as well as human tissue samples. CLE allows visualization of the underlying tissue on a microscopic scale, receiving information on the microstructure as well as cellular components. However, the clinical importance of this technique for its application in neurosurgery will be demonstrated in this clinical trial.

Study Overview

• Status: Completed
• Conditions: Brain Tumor; Surgery; Convivo System; Laser Endomicroscopy
• Intervention / Treatment: Device: CONVIVO

Detailed Description

Background:

The prognosis of glioblastoma patients highly depends on resection extent. Various strategies have been introduced to overcome the dilemma of intraoperative tumor identification.

In gastroenterology, confocal laser endomicroscopy (CLE) allows precise differentiation of tumor tissue from surrounding mucosa in various diseases. Combining high-definition white light endoscopy with CLE significantly increases sensitivity and specificity compared with the sole application of high-definition white light endoscopy.

CLE was recently introduced to neurosurgical applications. Although still in an early stage of clinical application, this technique has proven to be capable of differentiating various tumor entities in animal models as well as human tissue samples. CLE allows visualization of the underlying tissue on a microscopic scale, receiving information on the microstructure as well as cellular components. However, the clinical importance of this technique for its application in neurosurgery still needs to be demonstrated

Methods:

Intravenous injection dose of fluorescein sodium. For every operation the investigators plan to take pictures with the CONVIVO system before taking the material for standard frozen section and definitive histopathology. These pictures will be evaluated by a pathologist afterwards.

Objectives:

The primary objective of this trial is to demonstrate, that the CONVIVO system allows identification of tumor tissue. The secondary objectives are procedural aspects and handling issues covering the usability.

• Study Type: Interventional
• Enrollment (Actual): 174
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Bern, Switzerland, 3010
    • Dep. of Neurosurgery, Bern University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• The patient is undergoing neurosurgery for a suspected brain tumor and amenable to surgical resection by fluorescent guided technique
• The patient has an indication for tumor resection
• Macroscopic tumor visualization using sodium fluorescein is planned, concentration 5-10mg/kg
• The patient is older than 18 years
• Written consent

Exclusion Criteria:

• Stereotactic biopsy procedure
• Patients with any kind of contraindication to the use of fluorescein sodium
• Vulnerable persons (pregnant women, patients with Glasgow Coma Scale below 14)
• Participation in other ongoing clinical trials with one exception: double inclusions are allowed provided that no interaction with NaF is to be expected
• People who do not want to participate in the study
• Tumors that do not exactly match the inclusion criteria
• Emergency procedures in which no consent was obtained before the operation.
• Multiple surgeries on the same patient.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CONVIVO; tumor tissue identification with the CONVIVO system	Device: CONVIVO; tumor tissue with the CONVIVO system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Identification of tumor tissue	Identification of tumor tissue versus non-affected tissue by the CONVIVO system in comparison to the histopathology of frozen section	End of surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accuracy of CONVIVO results	Accuracy of CONVIVO results compared with results of final tumor histopathology	14 days after surgery
Time for tissue visualization with the CONVIVO system	Intraoperative time for the tissue visualization with the CONVIVO system	End of surgery
Rate of unclear visualizations	Rate of unclear visualizations in %	14 days after surgery

Collaborators and Investigators

• Sponsor: Insel Gruppe AG, University Hospital Bern
• Investigators: Principal Investigator: Kathleen Seidel, MD, Principal Investigator

Study record dates

Study Major Dates

• Study Start (Actual): June 5, 2020
• Primary Completion (Actual): June 13, 2023
• Study Completion (Actual): June 30, 2023

Study Registration Dates

• First Submitted: February 20, 2020
• First Submitted That Met QC Criteria: February 20, 2020
• First Posted (Actual): February 21, 2020

Study Record Updates

• Last Update Posted (Actual): July 5, 2023
• Last Update Submitted That Met QC Criteria: July 3, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neoplasms; Neoplasms by Site; Central Nervous System Neoplasms; Nervous System Neoplasms; Brain Neoplasms
• Other Study ID Numbers: CONVIVO

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No