Diagnostic value of dynamic contrast-enhanced CT with perfusion imaging in the quantitative assessment of tumor response to sorafenib in patients with advanced hepatocellular carcinoma: A feasibility study

Purpose To investigate the feasibility of perfusion-CT (p-CT) measurements in quantitative assessment of hemodynamic changes related to sorafenib in patients with advanced hepatocellular carcinoma (HCC). Materials and methods Twenty-two patients with advanced HCC underwent p-CT study (256-MDCT scanner) before and 2 months after sorafenib administration. Dedicated perfusion software generated a quantitative map of arterial and portal perfusion and calculated the following perfusion parameters in target liver lesion: hepatic perfusion (HP), time-to-peak (TTP), blood volume (BV), arterial perfusion (AP), and hepatic perfusion index (HPI). After the follow-up scan, patients were categorized as responders and non-responders, according to mRECIST. Perfusion values were analyzed and compared in HCC lesions and in the cirrhotic parenchyma (n = 22), such as between baseline and follow-up in progressors and non-progressors. Results Before treatment, all mean perfusion values were significantly higher in HCC lesions than in the cirrhotic parenchyma (HP 47.8 ± 17.2 vs 13.3 ± 6.3 mL/s per 100 g; AP 47.9 ± 18.1 vs 12.9 ± 10.7 mL/s; p < 0.001). The group that responded to sorafenib (n = 17) showed a significant reduction of values in HCC target lesions after therapy (HP 29.2 ± 23.3 vs 48.1 ± 15.1; AP 29.4 ± 24.6 vs 49.2 ± 17.4; p < 0.01), in comparison with the non-responder group (n = 5) that demonstrated no significant variation before and after treatment of HP (46.9 ± 25.1 vs 46.7 ± 24.1) and AP (43.4 ± 21.7 vs 43.5 ± 24.6). Among the responder group, HP percentage variation (Δ) in target lesions, during treatment, showed a significantly different (p = 0.04) ΔHP in the group with complete response (79%) compared to the group with partial response or stable disease (16%). Conclusions p-CT technique can be used for HCC quantitative assessment of changes related to anti-angiogenic therapy. Identification of response predictors might help clinicians in selection of patients who may benefit from targeted-therapy allowing for optimization of individualized treatment.