Xin'an, L., Jianying, Z., Lizhi, N., Fei, Y., Xiaohua, W., Jibing, C., . . . Kecheng, X. (2014). P0079 alleviating the pain of unresectable hepatic tumours by percutaneous cryoablation: Experience in 73 patients. European Journal of Cancer, 50(Suppl. 4), E31. 

To review the changes in the severity of pain before and after percutaneous cryoablation of hepatic tumors

Patients with large tumors (major diameter P5 cm) underwent transarterial chemoembolization (TACE) first and then cryoablation. Cryosurgeries of hepatic tumors were performed on all 73 patients using an argon gas-based cryosurgical unit with two freeze/thaw cycles. Maximal freezing time was 15 minutes followed by natural thawing for 5 minutes x 2. A margin of at least 1 cm of normal hepatic tissue was frozen circumferentially around the tumor.

• N = 73  
• AGE RANG = 25–80 years (mean not noted)
• MALES: 40, FEMALES: 33
• KEY DISEASE CHARACTERISTICS: 29 patients had hepatocellular carcinoma; 44 patients had metastatic lesions in the liver; cancer was not invading major vessels; only 17 patients had pain.
• OTHER KEY SAMPLE CHARACTERISTICS: KPS > 70%, platelet count ≥ 80,000, white blood cell count ≥ 3x10⁹/l, neutrophil count ≥ 2x10⁹/ l, hemoglobin ≥ 9 g/l, prothrombin time international normalized ratio ≥ 1.5, adequate hepatic and liver function 

• SITE: Single-site    
• SETTING TYPE: Outpatient    
• LOCATION: China

• PHASE OF CARE: End-of-life care
• APPLICATIONS: Palliative care 

• Intervention study: One-group design

• Pain intensity scale 0–10 (0 indicating no pain and 10 indicating worst pain imaginable) with severe pain classified as 5–10

Six patients had an immediate relief of severe pain, 11 had relief within 15 days of cryosurgery (these were of the 17 patients with pain prior to the procedure), 39 were always pain-free, and 17 had new pain with the procedure but total relief within 15 days.

The pain-relieving effect of cryosurgery was immediate for some patients but all eventually experienced the complete disappearance of pain for at least eight weeks. Pain relief was delayed for some patients due to edema, which resulted from the treatment.

• Small sample (< 100)
• Risk of bias (no control group)
• Risk of bias (no blinding) 
• Risk of bias (no random assignment) 
• Risk of bias (no appropriate attentional control condition)  
• Intervention expensive, impractical, or training needs

Cryoablation is a potential pain-relieving treatment for primary and metastatic tumors of the liver, but more studies are needed before this can be recommended as a modality to manage pain. Evidence to support long-term results beyond eight weeks also is lacking.