A Prospective Phase II Study Evaluating Intraoperative Electrochemotherapy of Hepatocellular Carcinoma

SIMPLE SUMMARY: Electrochemotherapy is fast developing local ablative therapy that is nowadays being adapted also for the treatment of deep-seated tumors. The first reports demonstrated the feasibility and safety of the procedure in liver tumors, i.e., colorectal liver metastases and hepatocellular carcinoma (HCC). This prospective phase II study aimed to investigate the effectiveness and long-term safety of electrochemotherapy in the treatment of primary HCC not suitable for other treatment options. Electrochemotherapy was performed intraoperatively in 24 patients and proved to be effective, feasible, and safe with some procedure-related side effects. In the 32 treated tumors, a high response rate was achieved: 84.4% complete responses, 12.5% partial responses, and 3.1% stable disease with the durable response over 50 months in 78.0% of the treated nodules. Based on the current evidence, electrochemotherapy (ECT) can be considered as a treatment option for HCC in the cirrhotic liver not suitable for other curative treatment options according to the Barcelona Clinic Liver Cancer classification (BCLC) classification. ABSTRACT: The aim of this clinical study was to investigate the effectiveness and long-term safety of electrochemotherapy as an emerging treatment for HCC in patients not suitable for other treatment options. A prospective phase II clinical study was conducted in patients with primary HCC who were not suitable for other treatment options according to the Barcelona Clinic Liver Cancer classification. A total of 24 patients with 32 tumors were treated by electrochemotherapy. The procedure was effective, feasible, and safe with some procedure-related side effects. The responses of the 32 treated nodules were: 84.4% complete response (CR), 12.5% partial response (PR), and 3.1% stable disease (SD). The treatment was equally effective for nodules located centrally and peripherally. Electrochemotherapy provided a durable response with local tumor control over 50 months of observation in 78.0% of nodules. The patient responses were: 79.2% CR and 16.6% PR. The median progression-free survival was 12 months (range 2.7–50), and the overall survival over 5 years of observation was 72.0%. This prospective phase II clinical study showed that electrochemotherapy was an effective, feasible, and safe option for treating HCC in patients not suitable for other treatment options.