Histogram analysis of apparent diffusion coefficient predicts response to radiofrequency ablation in hepatocellular carcinoma.

Xiaohong Ma,Xinming Zhao,Shuang Wang,Han Ouyang,Chunwu Zhou,Meng Wang

doi:10.21147/j.issn.1000-9604.2019.02.11

Abstract

ObjectiveThe aim of this study was to predict tumor progression in patients with hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA) using histogram analysis of apparent diffusion coefficients (ADC).MethodsBreath-hold diffusion weighted imaging (DWI) was performed in 64 patients (33 progressive and 31 stable) with biopsy-proven HCC prior to RFA. All patients had pre-treatment magnetic resonance imaging (MRI) and follow-up computed tomography (CT) or MRI. The ADC values (ADC10, ADC30, ADCmedian and ADCmax) were obtained from the histogram’s 10th, 30th, 50th and 100th percentiles. The ratios of ADC10, ADC30, ADCmedian and ADCmax to the mean non-lesion area-ADC (RADC10, RADC30, RADCmedian, and RADCmax) were calculated. The two patient groups were compared. Key predictive factors for survival were determined using the univariate and multivariate analysis of the Cox model. The Kaplan-Meier survival analysis was performed, and pairs of survival curves based on the key factors were compared using the log-rank test. ResultsThe ADC30, ADCmedian, ADCmax, RADC30, RADCmedian, and RADCmax were significantly larger in the progressive group than in the stable group (P<0.05). The median progression-free survival (PFS) was 22.9 months for all patients. The mean PFS for the stable and progressive groups were 47.7±1.3 and 9.8±1.3 months, respectively. Univariate analysis indicated that RADC10, RADC30, and RADCmedian were significantly correlated with the PFS [hazard ratio (HR)=31.02, 43.84, and 44.29, respectively, P<0.05 for all]. Multivariate analysis showed that RADCmedian was the only independent predictor of tumor progression (P=0.04). And the cutoff value of RADCmedian was 0.71. ConclusionsPre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA.

Highlights

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world [1], and the second leading cause of cancer-related deaths in China [2]
The ADC30, ADCmedian, ADCmax, RADC30, RADCmedian and RADCmax were significantly larger in the progressive group than in the stable group (P
We demonstrated that the apparent diffusion coefficients (ADC) and RADC values before the radiofrequency ablation (RFA) were larger in the progressive group than in the stable group, and the higher pre-treatment ADC and RADC values were associated with the shorter progression-free survival (PFS)

Summary

Introduction

Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world [1], and the second leading cause of cancer-related deaths in China [2]. Diffusion weighted imaging (DWI) quantitatively evaluates the response to cancer therapy from changes in apparent diffusion coefficients (ADC). These changes occur early, and are apparent before any changes in tumor morphology [1,8]. Previous studies have demonstrated that ADC histogram analysis was effective for diagnosis, evaluation of biologic aggressiveness, and prediction of therapy response in glioblastoma, testicular germ cell tumors and colorectal hepatic metastases [10,11,14]. The purpose of our study was to predict therapeutic effects of RFA treatment on HCC patients using ADC histogram parameters obtained before RFA treatment, and determine key parameters that can best predict the efficacy of RFA treatment

Materials and methods

Results

Conclusions