MicroRNA-34a expression is predictive of recurrence after radiofrequency ablation in early hepatocellular carcinoma

The prognosis of hepatocellular carcinoma (HCC) treated by radiofrequency ablation (RFA) is mainly associated with tumor recurrence. So far, no tissue biomarker of recurrence has been confirmed in biopsy specimens. Previous studies have reported that aberrant expression of microRNA-34a (miR-34a) is involved in oncogenesis and progression of HCC. The aim of this study was to investigate the prognostic value of tissue miR-34a expression in patients with HCC treated with RFA. Patients with early-stage single-nodule HCC treated with RFA were included, and tissue expression of miR-34a were assessed by quantitative reverse-transcription polymerase chain reaction. Main clinical endpoints were overall and early recurrence. The Kaplan-Meier method was used to plot recurrence curves and univariable and multivariable Cox regression analyses were performed to assess independent predictive factors for recurrence. Of 120 patients, recurrence occurred in 67 patients (55.8 %) with a median follow-up of 31 months. Forty-one patients (34.2 %) recurred within 2 years after RFA. The median miR-34a level was 0.87 (range 0.06–21.54). Low miR-34a level was associated with larger tumor size (P = 0.033) and higher serum alpha-fetoprotein (AFP) level (P = 0.004). When analyzed with a Cox regression model, the two independent predictive factors for overall recurrence were high serum AFP level (hazard ratio [HR] = 1.21; 95 % confidence interval [CI] = 1.04–1.36; P = 0.039) and low miR-34a level (HR = 1.44; 95 % CI = 1.13–1.72; P = 0.011). The expression of miR-34a was also an independent predictive factor for early recurrence (HR = 1.49; 95 % CI = 1.15–1.79; P = 0.008). Taken together, this study suggests that the expression of miR-34a in HCC biopsy specimens has an independent predictive value of early recurrence after RFA.