Evaluation of the Efficacy of Sorafenib on Overall Survival in Patients with Hepatocellular Carcinoma using FT Rate: A Devised Index

INTRODUCTION: Transcatheter arterial chemoembolization (TACE) is the first-line treatment for intermediate stage hepatocellular carcinoma (HCC) and prolongs survival in HCC patients. However, repeated TACE results in diminished therapeutic response. In addition, the superiority of sorafenib to TACE monotherapy or combined therapy in patients with HCC is still controversial. The prognosis of HCC has many variables and, thus, the effect of a specific treatment is difficult to evaluate. The frequency of treatments per year (FT rate) used in this study was obtained by dividing the total number of radiofrequency ablations and TACE or transcatheter arterial infusion treatments by the years of survival. The aim of this study was to evaluate the overall survival (OS) of TACE versus sorafenib using the FT rate. METHODS: We compared the OS of patients with recurrence of HCC receiving repeated TACE monotherapy (CON) with those receiving therapy switched from TACE to sorafenib (SOR). In addition, a one-to-one FT rate matching cohort consisting of matched SOR (mSOR) and matched CON (mCON) was determined using the propensity score matching method, and OS in the cohort was evaluated. Factors influencing survival were evaluated using Cox proportional hazard regression analysis in all patients and the FT rate matched cohort. RESULTS: In the FT rate matched cohort, the cumulative survival rate was significantly higher in the mSOR group compared with the mCON group. Multivariate regression analysis of the FT rate matched cohort showed the FT rate and sorafenib to be significant variables for survival with a hazard ratio (HR) of 2.86 (p < 0.001) and 0.42 (p = 0.008), respectively. CONCLUSION: Early switching from TACE to sorafenib therapy may prolong OS in HCC patients unresponsive to TACE. The present study indicates that the FT rate is potentially a useful index in evaluating the outcome for patients at various stages and treatment regimens. FUNDING: Bayer Yakuhin, Ltd.