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

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

doi:10.21147/j.issn.1000-9604.2019.02.11

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

Chin J Cancer Res. 2019 Apr;31(2):366-374. doi: 10.21147/j.issn.1000-9604.2019.02.11.

Authors

Xiaohong Ma¹, Han Ouyang¹, Shuang Wang¹, Meng Wang², Chunwu Zhou¹, Xinming Zhao¹

Affiliations

¹ Department of Diagnostic Radiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021, China.
² Department of Epidemiology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021, China.

PMID: 31156307
PMCID: PMC6513745
DOI: 10.21147/j.issn.1000-9604.2019.02.11

Abstract

Objective: The 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).

Methods: Breath-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, ADC_median and ADC_max) were obtained from the histogram's 10th, 30th, 50th and 100th percentiles. The ratios of ADC₁₀, ADC₃₀, ADC_median and ADC_max to the mean non-lesion area-ADC (RADC₁₀, RADC₃₀, RADC_median, and RADC_max) 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.

Results: The ADC₃₀, ADC_median, ADC_max, RADC₃₀, RADC_median, and RADC_max 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 RADC_median 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 RADC_median was the only independent predictor of tumor progression (P=0.04). And the cutoff value of RADC_median was 0.71.

Conclusions: Pre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA.

Keywords: Diffusion-weighted imaging; apparent diffusion coefficient; hepatocellular carcinoma; histogram analysis; radiofrequency ablation; survival time.