Background: This study aims to test whether 5% lidocaine patches can reduce Radiofrequency ablation-induced pain. Methods: The study will enroll patients with hepatocellular carcinoma and schedule a radiofrequency ablation procedure. 200 patients will be invited to allocate randomly into study or control groups: pretreatment with a 5% lidocaine patch (LidotopⓇ) (Group A); pretreatment with a placebo patch (Group B); The skin patch is applied before Radiofrequency ablation (RFA) while admission, and is changed every day till discharge. Pain severity is evaluated by a visual analog scale using a 10-point scale recorded by a study nurse before RFA and after the procedure. The demographic data, hepatocellular carcinoma characteristics, analgesics usage, patient satisfaction with pain control, and visual analog scale will be compared between the two groups. Anticipated results: Pretreatment with 5% lidocaine patches is an effective and straight method of reducing Radiofrequency ablation-induced pain to reduce analgesics usage and improve patient satisfaction with pain control.

Inclusion Criteria:

1. Adults diagnosed with liver cancer (HCC) by a physician and eligible for radiofrequency cautery (RFA).
2. Age is > = 18 years.
3. Whether there is cirrhosis combined with cirrhosis, the child-pugh score of those with cirrhosis must score < 8 points.
4. Communicative and able to express pain sensations.

Exclusion Criteria:

1. Those who are allergic to Lidocaine.
2. Those who suffer from skin diseases or have wounds on the abdomen that cannot be patched.