Limitations of Fluorine 18 Fluoromisonidazole in Assessing Treatment-induced Tissue Hypoxia after Transcatheter Arterial Embolization of Hepatocellular Carcinoma: A Prospective Pilot Study.

Purpose To determine the variance and correlation with tumor viability of fluorine 18 (18F) fluoromisonidazole (FMISO) uptake in hepatocellular carcinoma (HCC) prior to and after embolization treatment. Materials and Methods In this single-arm, single-center, prospective pilot study between September 2016 and March 2017, participants with at least one tumor measuring 1.5 cm or larger with imaging or histologic findings diagnostic for HCC were enrolled (five men; mean age, 68 years; age range, 61-76 years). Participants underwent 18F-FMISO PET/CT before and after bland embolization of HCC. A tumor-to-liver ratio (TLR) was calculated by using standardized uptake values of tumor and liver. The difference in mean TLR before and after treatment was compared by using a Wilcoxon rank sum test, and correlation between TLR and tumor viability was assessed by using the Spearman rank correlation coefficient. Results Four participants with five tumors were included in the final analysis. The median tumor diameter was 3.2 cm (IQR, 3.0-3.9 cm). The median TLR before treatment was 0.97 (IQR, 0.88-0.98), with a variance of 0.02, and the median TLR after treatment was 0.85 (IQR, 0.79-1), with a variance of 0.01; both findings indicate a narrow range of 18F-FMISO uptake in HCC. The Spearman rank correlation coefficient was 0.87, indicating a high correlation between change in TLR and nonviable tumor. Conclusion Although there was a correlation between change in TLR and response to treatment, the low signal-to-noise ratio of 18F-FMISO in the liver limited its use in HCC. Keywords: Molecular Imaging-Clinical Translation, Embolization, Abdomen/Gastrointestinal, Liver Clinical trial registration no. NCT02695628 © RSNA, 2022.

PCI Alternative Using Sustained Exercise (PAUSE): Rationale and trial design.

Cardiovascular disease (CVD) currently claims nearly one million lives yearly in the US, accounting for nearly 40% of all deaths. Coronary artery disease (CAD) accounts for the largest number of these deaths. While efforts aimed at treating CAD in recent decades have concentrated on surgical and catheter-based interventions, limited resources have been directed toward prevention and rehabilitation. CAD is commonly treated using percutaneous coronary intervention (PCI), and this treatment has increased exponentially since its adoption over three decades ago. Recent questions have been raised regarding the cost-effectiveness of PCI, the extent to which PCI is overused, and whether selected patients may benefit from optimal medical therapy in lieu of PCI. One alternative therapy that has been shown to improve outcomes in CAD is exercise therapy; exercise programs have been shown to have numerous physiological benefits, and a growing number of studies have demonstrated reductions in mortality. Given the high volume of PCI, its high cost, its lack of effect on survival and the potential for alternative treatments including exercise, the current study is termed "PCI Alternative Using Sustained Exercise" (PAUSE). The primary aim of PAUSE is to determine whether patients randomized to exercise and lifestyle intervention have greater improvement in coronary function and anatomy compared to those randomized to PCI. Coronary function and anatomy is determined using positron emission tomography combined with computed tomographic angiography (PET/CTA). Our objective is to demonstrate the utility of a non-invasive technology to document the efficacy of exercise as an alternative treatment strategy to PCI.