Apparent diffusion coefficient can predict therapy response of hepatocellular carcinoma to transcatheter arterial chemoembolization

Abstract

Aim: The goal of this meta-analysis was to assess the apparent diffusion coefficient (ADC) as a pre- and posttreatment (ΔADC) predictive imaging biomarker of response to transcatheter arterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC). Methods: SCOPUS database, EMBASE database and MEDLINE library were scanned for connections between pre- and posttreatment ADC values of HCC and response to TACE. Six studies qualified for inclusion. The following parameters were collected: authors, publication year, study design, number of patients, drugs for TACE, mean ADC value, standard deviation, measure method, b-values and Tesla-strength. The QUADAS-2 instrument was employed to check the methodological quality of each study. The meta-analysis was performed by utilizing RevMan 5.3 software. DerSimonian and Laird random-effects models with inverse-variance were used to regard heterogeneity. Mean ADC values and 95% confidence intervals were computed. Results: Six studies (n=271 patients with 293 HCC nodules) were included. The pretreatment mean ADC in the responder group was 1.20 x 10-3 mm2/s (0.98, 1.42) and 1.14 x 10-3 mm2/s (0.89, 1.39) in the non-responder group. The analysis of post TACE ADC value changes (ΔADC) revealed a threshold of ≥ 20% to identify treatment responders. No suitable pretreatment ADC threshold to predict therapy response or discriminate between responders and non-responders before therapy could be discovered. Conclusion: ΔADC can facilitate early objective response evaluation through post-therapeutic ADC alterations ≥ 20%. Pretreatment ADC cannot predict response to TACE.