Novel Endoscopic Imaging Methods for the Evaluation of Blood Vessels in Gastrointestinal Cancers

Summary

The aim of the project is to study the role of minimally invasive imaging methods, such as magnification endoscopy with narrow-band imaging (M-NBI) combined with confocal laser endomicroscopy (CLE), in correlation with immunohistochemical analysis, for assessing the angiogenesis status of patients with gastrointestinal tumors, in particular with colorectal and gastric cancer. Angiogenesis, i.e. the process of forming new blood vessels, represents an essential event for tumor growth and metastasis and the importance of its understanding stems from potential applications for diagnosis, prognosis stratification and mainly from the possibility of developing and improving targeted therapies. While current methods for evaluating tumor vascularity are based on immunohistochemistry techniques with microvascular density (MVD) calculations, these imply repeated tissue sampling and are not feasible in the context of clinical practice. Imaging techniques might overcome limitations associated with MDV measuring, obtaining both functional and morphological information and enabling repeated evaluations that are necessary for the assessment of a dynamic process as angiogenesis during follow-up of targeted therapies.

NBI is a digitally enhanced endoscopic imaging technique that uses optical filters to illuminate tissue with light at blue and green wavelengths. These are selectively absorbed by hemoglobin and, as a result superficial vascular networks are highlighted and morphological changes in capillary patterns can be described for different lesions. CLE represents a revolutionary technology that enables endoscopists to collect real-time in vivo histological images or "virtual biopsies" of the gastrointestinal mucosa during endoscopy, and has raised significant interest for the potential clinical applications and numerous research possibilities. After intravenous administration of fluorescein as a contrast agent, CLE enables real-time visualization of the tumor vasculature, which is structurally and functionally altered compared to the normal vascular networks. Therefore M-NBI will be used for enhanced visualization of morphological changes of the superficial capillaries, while CLE will be directed towards vascular regions of interest for characterization of these changes at the microscopic level. Furthermore, imaging studies will be backed by MVD calculation using immunohistochemical methods, based on tissue samples harvested during endoscopic procedures.

Conditions

• Gastric Cancer
• Colorectal Cancer
• Gastrointestinal Neoplasms

Interventions

PROCEDURE

Magnification endoscopy with narrow band imaging

Magnification endoscopy with narrow band imaging is an optically enhanced endoscopic imaging technique used for better characterization of lesions as compared to white light endoscopy alone. With only a push of a button optical filters are applied to reduce the illuminating light to 415 nm (blue) and 540 nm (green) wavelengths, which are selectively absorbed by haemoglobin. As a result the superficial vascular networks are highlighted and morphological changes in capillary patterns can be described for different gastrointestinal lesions.

DEVICE

Probe based confocal laser endomicroscopy

Confocal laser endomicroscopy enables in vivo microscopic analysis during ongoing endoscopy and has shown good accuracy for predicting the histopathological diagnosis in lesions of both the upper and lower GI tract. During the examination fluorescein is administered intravenously as a contrast agent, highlighting the vessels and surrounding epithelial structures. The probe based confocal laser endomicroscopy system can be easily integrated into the imaging protocol as it uses flexible catheter probes that can be passed through the working channels of the endoscopes once the area of interest has been identified.

Sponsors & Collaborators

• University of Medicine and Pharmacy Craiova

  lead OTHER

Principal Investigators

• Dan I. Gheonea, Assoc. Prof. · University of Medicine and Pharmacy Craiova

Study Design

Allocation

NON_RANDOMIZED

Purpose

DIAGNOSTIC

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

90 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2015-10-31

Primary Completion

2017-02-28

Completion

2017-09-30

Countries

• Romania

Study Locations