There is a need for improved visualization of presence and extent of pituitary neuroendocrine tumor (PitNET) tissue during transsphenoidal surgery (TSS), especially in tumors invading the cavernous sinus (CS). Optical molecular imaging of PitNET associated biomarkers is a promising technique to accommodate this need. Vascular Endothelial Growth Factor (VEGF-A) is overexpressed in PitNET tissue compared to normal pituitary tissue and has proven to be a valid target for molecular imaging. Bevacizumab is an antibody that binds VEGF-A. By conjugating a fluorescent dye to this antibody, the fluorescent tracer molecule bevacizumab-800CW is created, which binds to VEGF-A. The investigators hypothesize that bevacizumab-800CW accumulates in PitNET tissue, enabling visualization using a molecular fluorescence endoscopy system. In this pilot intervention study the investigators will determine the feasibility of using microdoses (4.5, 10 and 25 mg) of bevacizumab-800CW to detect PitNET tissue intraoperatively.
Study Type
INTERVENTIONAL
Allocation
NON_RANDOMIZED
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
20
Intravenous administration of 4.5, 10 or 25 mg of Bevacizumab-IRDye800CW prior to endoscopic transsphenoidal surgery
A flexible fluorescence fiber-bundle is attached to a fluorescence camera platform to enable the detection of fluorescence signals. The fluorescence fiber-probe is inserted through the standard working channel of the Surgvision explorer endoscope. During surgery, three imaging moments are defined in which the fluorescence molecular endoscopy system will detect the fluorescent signal
University Medical Center Groningen
Groningen, Netherlands
Discrimination of tumorous and non-tumorous tissue based on in vivo and ex vivo fluorescence measurements from bevacizumab-800CW gained during fluorescence endoscopic transsphenoidal surgery of pituitary neuroendocrine tumors (PitNETs)
To determine the sensitivity of the marker bevacizumab-800CW in discriminating between tumorous and non-tumorous tissue during endoscopic transsphenoidal surgery of pituitary neuroendocrine tumors (PitNETs) defined as the tumor to background ratio and intrinsic fluorescence
Time frame: Three days after tracer injection
Number of participants with adverse events (AE), serious adverse events (SAE) and suspected unexpected serious adverse reactions (SUSAR)
Data collection as a measure of safety and tolerability regarding administration of bevacizumab-800CW
Time frame: Up to 7 days after tracer injection
The correlation of in vivo and ex vivo fluorescent signals to histopathological analysis results
Correlate the H/E images to the fluorescent images made with multiple ex vivo imaging modalities
Time frame: Up to 1,5 year
Quantification of the fluorescent signal by MDSFR/SFF spectroscopy
Multi-diameter single-fiber reflectance with single-fiber fluorescence (MDSFR/SFF) spectroscopy can measure the fluorescence signal quantitatively, both in vivo and ex vivo
Time frame: Up to 1,5 year
Assessment of the (sub)-cellular distribution of bevacizumab-800CW by ex vivo fluorescence microscopy
Imaging of the distribution of bevacizumab-800CW with a fluorescence microscope
Time frame: Up to 1,5 year
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