Probe-based confocal laser endomicroscopy for in vivo evaluation of the tumor vasculature in gastric and rectal carcinomas

Abstract

Probe-based Confocal Laser Endomicroscopy (pCLE) is a powerful imaging technique that allows to perform gastrointestinal endomicroscopy at subcellular resolution. The aim of this study was to assess the use of pCLE to evaluate tumor angiogenesis in rectal and gastric cancers. A total of 35 consecutive patients with gastric and 91 with rectal carcinomas underwent endoscopy and pCLE during the same examination. Vascular assessment was based on vessel shape and size, vessel permeability and blood flow, and allowed the creation of an angiogenic score ranging from 0, for normal vasculature, to 4, for aberrant vasculature. A significant difference for the presence of vessels with large diameter and defective blood flow was found between rectal and gastric cancers. Overall, rectal cancers displayed a higher angiogenic score compared to gastric cancers. Conventional therapy induced a striking reduction in the angiogenic score only in rectal cancer patients. Taken together, our findings suggest that the pCLE technology is suitable for the evaluation of the tumor microvasculature abnormalities. Therefore, the real-time assessment of the vasculature status may represent a promising approach to predict the efficacy of the treatments and improve the clinical management of patients with gastric or rectal carcinomas.

Loss of Multimerin-2 and EMILIN-2 Expression in Gastric Cancer Associate with Altered Angiogenesis

“…To this end patients affected by gastric cancer were injected with fluorescein and tumor vascularization was assessed by probe-based confocal laser endomicroscopy (pCLE) during the gastric endoscopy procedure. As previously demonstrated this procedure allows the in vivo evaluation of different parameters affecting vascular efficiency such as vessel diameter, tortuosity, leakiness and vessels defective flow [55,56]. The results of the analyses performed on a representative patient are reported in Figure 1 and the relative video in Supplemental Video S1.…”

Inhibition of the CCL5/CCR5 Axis against the Progression of Gastric Cancer

“…In addition, both GC tumor and stromal cells produce various angiogenic factors, including VEGF, IL-8, and platelet-derived endothelial cell growth factor (PD-ECGF). Tumor angiogenesis plays an essential role in growth, invasion, and metastatic spread of GC [ 96 ], indicating that pharmacologic blockade of angiogenesis is a promising new therapy, and that the real-time assessment of the vasculature status is a promising approach to predict the efficacy of the treatments and improve the clinical management of patients with GC [ 97 ]. Indeed, high levels of angiogenic factors in serum and tumors are associated with worse outcomes in GC patients.…”

Reduced Intravenous Fluorescein Dose for Upper and Lower Gastrointestinal Tract Probe-Based Confocal Laser Endomicroscopy

“…Recent investigations have demonstrated that fluorescein leakage reflects microcirculatory disturbances and is considered to be an important finding to identify malignant lesions or inflammatory mucosa of ulcerative colitis. [25][26][27] The present study has several limitations. Firstly, this is a pilot study and it is difficult to draw a solid conclusion; nevertheless, it highlights the potential dose reduction of IV fluorescein during pCLE.…”