Imaging Assessment of Hepatocellular Carcinoma Response to Locoregional and Systemic Therapy

Abstract

The evaluation of tumor response after systemic and locoregional therapies is essential in directing management for HCC. An understanding of the various therapeutic strategies and of their posttherapy imaging appearances is essential for accurately assessing treatment response. The evaluation of tumor response should include not only anatomic imaging biomarkers, such as reduction in tumor size, but also tumor enhancement and necrosis.

3D versus 2D contrast-enhanced sonography in the evaluation of therapeutic response of hepatocellular carcinoma after locoregional therapies: preliminary findings

“…A four-year long follow-up with MR and CT confirmed the stability of this area, eventually considered as an arterial-dependent hyperperfusion defect following RFA which showed increased arterial contrast enhancement on all imaging modalities, including CT, MRI, and CEUS [19]. Although some authors consider any nodular arterially enhancing area within or along the margin of the ablated zone suspicious of viable tumor, our finding suggests that including the washout sign may improve the specificity in the detection of viable tumoral tissue after LRT [10,20]. The presence of a thin peripheral rim of benign reactive hyperemia was observed in 2 cases, without misinterpretation by the readers.…”

“…Diagnostic criteria for complete treatment at MRI/MDCT were the absence of any enhancing portion within or at the margin of the ablation zone during the hepatic arterial phase, as previously reported [12]. Diagnostic criteria for residual viable tumoral tissue at MRI/MDCT were any nodular arterially enhancing area within or along the margin of the treated HCC [10].…”

“…The two readers were also asked to report (1) complete response (CR): the absence of any nodular arterially enhancing portion within or at the margin of treated HCC; (2) residual tumor (RT): any nodular arterially enhancing area within or along the margin of the treated HCC [6,10]. Residual viable tumor was also categorized as (1) ingrowth pattern, when a hypervascular focus was detected within the edge of a treated nodule and (2) outgrowth pattern, when a hypervascular focus was detected around a necrotic treated nodule and in continuity with its border [11].…”

Immediate post‐doxorubicin drug‐eluting beads chemoembolization Mr Apparent diffusion coefficient quantification predicts response in unresectable hepatocellular carcinoma: A pilot study

“…33 Early posttherapy enhancement in such tumors may be due to coagulative hemorrhagic necrosis that may appear hyperintense on T 1 -weighted images, reactive edema, or granulation tissue and they may be mistaken for residual/untreated tumor. [34][35][36] Nevertheless, response criteria based on enhancement/necrosis of HCC treated with DEB-TACE have been previously shown to be independent predictors of survival. 7,19 Hence, a reproducible and clinically relevant imaging biomarker at an early timepoint, ideally immediately posttherapy, to predict future therapy response (ie, tumor necrosis) is desired.…”

Imaging Modalities for Assessment of Treatment Response to Nonsurgical Hepatocellular Carcinoma Therapy: Contrast-Enhanced US, CT, and MRI

“…The recommended techniques are contrast-enhanced CT or contrast-enhanced MRI. However, there are cases (e.g., infiltrative tumors, heterogeneous necrosis) and situations (e.g., after ablation) in which the mRECIST criteria are difficult or impossible to apply [30]. Other imaging techniques such as angiography, contrast-enhanced US, and positron emission tomography-CT are considered to be controversial.…”