Imaging of hypoxia in human tumors with [F-18]fluoromisonidazole

Evaluation of hypoxia in an experimental rat tumour model by [18F]Fluoromisonidazole PET and immunohistochemistry

“…Based on these normal and tumour tissue observations, a threshold of 1.4 was defined as cutoff value and as indicator of significant hypoxia. This cutoff value is in agreement with the results of Koh et al (1992).…”

“…Selection of normal tissue (lung, muscle and a body area 15 mm above the heart) for image analysis at 2 h p.i. using 2D ROIs, was performed in agreement with the literature (Koh et al, 1992;Bentzen et al, 2000). Mean activity ratios were calculated and 99% of the analysed ratios were below 1.1.…”

“…The choice to use the 2 h p.i. [ 18 F]FMISO-PET images was made for the evaluation of the tracer uptake, because this time point has been shown to be optimal for the examination of [ 18 F]FMISO uptake in tumours both in animal models (Kubota et al, 1999;TochonDanguy et al, 2002) and in humans (Koh et al, 1992;Valk et al, 1992). Selection of normal tissue (lung, muscle and a body area 15 mm above the heart) for image analysis at 2 h p.i.…”

“…The efflux area of the heart was defined with the aid of the early [ 18 F]FMISO perfusion images (summation of 1 -4 min of the first dynamic acquisition). Normal tissue evaluation was carried out using 2D-ROI analysis of the lung, muscle (cf Koh et al, 1992) and a body area 15 mm above the heart (cf Bentzen et al, 2000), and normal tissue to heart mean activity ratios were calculated. To assess the volume of [ 18 F]FMISO uptake in tumours, different absolute thresholds were used, ranging from 1.2 to 3.0.…”

“…Although the [ 3 H]misonidazole approach had limited clinical utility, it was the start of the development of noninvasive hypoxia markers based on 2-nitroimidazoles. The selective binding of [ 18 F]FMISO to hypoxic cells has been demonstrated in vitro as well as preclinically in vivo (Rasey et al, 1989;Koh et al, 1992). …”