Radiofrequency ablation combined with non-specific sequential immunotherapy for early hepatocellular carcinoma: a prospective study

Abstract

Objective To investigate the clinical effect of radiofrequency ablation (RFA) combined with non-specific sequential immunotherapy (IM) for early hepatocellular carcinoma (HCC), and analyze the factors affecting prognosis of patients after RFA. Methods The prosepctive study was conducted. The clinicopathological data of 72 early HCC patients who were admitted to the People′s Hospital of Guangxi Zhuang Autonomous Region from January 2009 to October 2015 were collected. Patients were divided into 3 groups by random number table: patients in group A underwent single RFA therapy; patients in group B underwent RFA + non-specific sequential IM (1-3 times); patients in group C underwent RFA + non-specific sequential IM (≥4 times). RFA was performed by the same doctors team, and non-specific sequential IM planning included thymalfasin + interleukin-2 (IL-2). Observation indicators: (1) treatment situations; (2) follow-up and survival; (3) analysis of prognostic factors after RFA. Follow-up using outpatient examination was performed to detect tumor recurrence and overall survival up to December 2015. Measurement data with normal distribution were represented as ±s, and comparison among groups were evaluated with the ANOVA. Comparison of count data were analyzed using the chi-square test. The curve, rate and time of tumor recurrence after treatment, overall survival curve and time were respectively drawn and calculated by the Kaplan-Meier method, and the Log-rank test was used for survival analysis. The univariate analysis and multivariate analysis were respectively done using the COX proportional hazard regression model. Results Seventy-two patients were screened for eligibility, including 31 in group A, 22 in group B and 19 in group C. (1) Treatment situations: patients in 3 groups underwent RFA, and contrast-enhanced ultrasound showed complete tumors ablation at 5 days postoperatively. Patients in group B and C didn′t have significant adverse reactions after RFA during IM therapy. (2) Follow-up and survival: 72 patients were followed up for 2-66 months after treatment, with a median time of 34 months. The 1-year tumor recurrence rates after treatment in group A, B and C were respectively 19.4%, 13.6% and 10.5%, with no statistically significant difference (χ2=0.714, P>0.05). The median tumor recurrence times in group A, B and C were respectively 24.0 months, 30.0 months and 33.0 months, with no statistically significant difference (χ2=3.283, P>0.05). The median overall survival times in group A, B and C were respectively 46.0 months, 56.0 months and 57.0 months, with a statistically significant difference (χ2=7.079, P 0.05). (3) Analysis of prognostic factors after RFA: results of univariate analysis showed that initial tumor, tumor number, Barcelona clinic liver cancer (BCLC) staging and sequential IM after RFA were related factors affecting prognosis of early HCC patients [hazard ratio (HR)=2.636, 2.530, 0.145, 0.582, 95% confidence interval (CI): 1.218-5.703, 1.110-5.767, 0.041-0.517, 0.321-0.867, P 1, staging B of BCLC and without sequential IM after RFA were independent risk factors affecting prognosis of early HCC patients (HR=2.376, 2.683, 0.567, 95%CI: 1.080-5.229, 1.530-21.112, 0.335-0.962, P<0.05). Conclusions The non-specific sequential IM of thymalfasin + IL-2 can prolong survival time of early HCC patients after RFA. Tumor number > 1, staging B of BCLC and without sequential IM after RFA are independent risk factors affecting prognosis of early HCC patients. Key words: Liver neoplasms; Radiofrequency ablation; Immunotherapy; Thymalfasin; Interleukin-2