RT Journal Article SR Electronic T1 99mTc-sulfur colloid SPECT/CT for quantitative imaging of global and regional liver function in hepatocellular carcinoma patients JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 584 OP 584 VO 55 IS supplement 1 A1 Bowen, Stephen A1 Nyflot, Matthew A1 Chapman, Tobias A1 Sandison, George A1 Kinahan, Paul A1 Miyaoka, Robert A1 Vesselle, Hubert A1 Apisarnthanarax, Smith YR 2014 UL http://jnm.snmjournals.org/content/55/supplement_1/584.abstract AB 584 Objectives Liver function assessment is critical in hepatocellular carcinoma (HCC) patient care and may be enhanced by quantitative imaging surrogates. Global and regional variability in 99mTc-sulfur colloid (SC) SPECT/CT liver uptake was tested for association to Child-Pugh (CP) score and prior therapy in HCC patients. Methods 12 HCC patients with variable CP score (A5-B9) and prior liver therapy underwent SC SPECT/CT scans. Reconstructed SPECT images were corrected for scatter, collimator blur and attenuation. Gross tumor volume (GTV), anatomic liver volume (ALV) and spleen were contoured on CT. Liver-to-spleen SC uptake ratios were calculated: maximum (L/Smax), mean (L/Smean) and total (L/Stotal). Functional liver volumes (FLV) were created by SC uptake thresholds within ALV. Heterogeneity was assessed by coefficient of variation in SC uptake (CVALV) and liver-to-spleen uptake ratio CV (L/SCV). Wilcoxon sign-rank tested image parameters across all patients and non-parameteric ANOVA tested differences between patient groups (CP score or prior treatment). Results FLV were smaller than ALV (FLV/ALV=53%, p<0.001) and SC uptake was heterogeneous (CVALV=0.44, p=0.001). Higher liver-to-spleen uptake ratios were associated with lower CP scores (superior liver function): L/Smax (CPA=1.6 vs. CPB=0.7, p=0.004), L/Smean (CPA=1.6 vs. CPB=0.5, p=0.004), L/Stotal (CPA=5.7 vs. CPB=1.2, p=0.03). Patients with lower CP score demonstrated higher %FLV/ALV (CPA=63% vs. CPB=47%, p=0.007). L/SCV trended lower in CPA patients (p=0.06), while CVALV was lower in untreated patients but did not reach significance (p=0.36). Conclusions Quantitative sulfur colloid SPECT/CT liver uptake distinguishes between patients with differential liver function. These imaging parameters may aid in personalization of HCC radiotherapy and delineation of functional avoidance volumes.