Parametric response mapping cut-off values that predict survival of hepatocellular carcinoma patients after TACE.

PURPOSE: Parametric response mapping (PRM) is a novel image-analysis technique applicable to assess tumor viability and predict intrahepatic recurrence of hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE). However, to date, the prognostic value of PRM for prediction of overall survival in HCC patients undergoing TACE is unclear. The objective of this explorative, single-center study was to identify cut-off values for voxel-specific PRM parameters that predict the post TACE overall survival in HCC patients. METHODS: PRM was applied to biphasic CT data obtained at baseline and following 3 TACE treatments of 20 patients with HCC tumors ≥ 2 cm. The individual portal venous phases were registered to the arterial phases followed by segmentation of the largest lesion, i.e., the region of interest (ROI). Segmented voxels with their respective arterial and portal venous phase density values were displayed as a scatter plot. Voxel-specific PRM parameters were calculated and compared to patients' survival at 1, 2, and 3 years post treatment to identify the maximal predictive parameters. RESULTS: The hypervascularized tissue portion of the ROI was found to represent an independent predictor of the post TACE overall survival. For this parameter, cut-off values of 3650, 2057, and 2057 voxels, respectively, were determined to be optimal to predict overall survival at 1, 2, and 3 years after TACE. Using these cut points, patients were correctly classified as having died with a sensitivity of 80, 92, and 86% and as still being alive with a specificity of 60, 75, and 83%, respectively. The prognostic accuracy measured by area under the curve (AUC) values ranged from 0.73 to 0.87. CONCLUSION: PRM may have prognostic value to predict post TACE overall survival in HCC patients.

Diagnostic value of alpha-1-fetoprotein (AFP) as a biomarker for hepatocellular carcinoma recurrence after liver transplantation.

BACKGROUND: Alpha-1-fetoprotein (AFP) is used to monitor progression, evaluate response to therapy and predict recurrence of hepatocellular carcinoma (HCC) in liver transplantation (LTx) patients. To date, the diagnostic value of serum AFP determinations for detecting tumor recurrence in HCC patients after LTx is unclear. OBJECTIVE: A retrospective, single-center, cross-sectional, non-interventional study was performed with the objective of determining post-transplant cut-off AFP values for detecting HCC recurrence post LTx. METHODS: Using receiver operating characteristic (ROC) analyses, post-transplant serum AFP values were evaluated against HCC recurrences in 63 HCC patients who had LTx between November 1995 and December 2011 at the University Medical Center Göttingen (UMG). Optimal and application-independent cut points for predicting tumor recurrence at 1, 3, and 5years after LTx were determined. RESULTS: Post-LTx serum AFP was found to represent an independent risk factor (predictor) for HCC relapse. Post-operative AFP cut-off values of 7µg/l, 6µg/l, and 6µg/l, respectively, were determined to be optimal at 1, 3, and 5years after LTx respectively for predicting a HCC relapse. Using these cut-off values, patients were correctly classified as relapse-positive with a diagnostic sensitivity of 79%, 81%, and 77%, and as relapse-free with a specificity of 82%, 79%, and 69%. The diagnostic accuracy measured by area under the curve (AUC) values ranged from 0.813 to 0.886. However, a limitation is that at a clinically relevant specificity of ≥95%, the analyses showed sensitivity values of only 50%, 52%, and 50%, respectively. CONCLUSION: Post-transplant serum AFP may have diagnostic value to detect HCC recurrence after LTx.