Treatment Of Liver Tumor With Radiofrequency Ablation Plus Intratumoral Injection Of Acetic Acid And Hypertonic Saline: An Experimental And Clinical Study

1. BackgroundHepatocellular carcinoma (HCC) is one of the most common malignant tumors. Radical surgery is indicated in only 20%-30% patients because of high degrees of malignancy and quick progression of HCC and poor liver functional reserve in patients with cirrhosis [1]. Currently, patients who are not suitable for surgery are mainly managed by local therapy, and non-operative therapy, such as transcatheter arterial chemoembolization (TACE), local ablation therapy (including exposure to microwave, radiofrequency, laser, freezing, percutaneous intratumoral injection of anhydrous alcohol or acetic acid ) plays essential roles in HCC therapy. As a representative technique for thermal ablation, radiofrequency ablation (RFA) has many advantages, such as being microinvasive, safe, and simple, allowing for repetitive operation, and giving rise to definite therapeutic effect; therefore, it has been advanced quickly in the previous decade. A RFA system consists of a RF generator, needle and skin electrodes. During therapy, the needle electrode is inserted into the tumor under the guidance of mode B ultrasound or CT, which generates 450-500 KHz alternating current. The current makes ions around the electrode oscillate and elevate temperature up to 90~100°C by friction, thus causing coagulation necrosis of local tissue. RFA has been extensively used in clinical practice, and it exhibits marked advantages particularly for unresectable or recurrent liver cancer of small to medium size [2,3]. Nevertheless, there are still some drawbacks, including limited size of tissue ablated each time, non-thoroughness of tumor therapy, and retention of perivascular tumor tissue due to thermal precipitation effect. Therefore, many authors have attempted to solve these problems. On one hand, radiofrequency equipment is improved to enhance the therapeutic effect; on the other hand, combination of RFA and other therapies are considered to enhance the therapeutic effect. To date, RFA+TACE and RFA+TACE+SPVE (Selective Portal Vein Embolization) have been studied intensively, but...