AIM:To investigate the effectiveness of phenol for the relief of cancer pain by endoscopic ultrasound-guided celiac plexus neurolysis(EUS-CPN).METHODS:Twenty-two patients referred to our hospital with cancer pain from August 2009 to July 2011for EUS-CPN were enrolled in this study.Phenol was used for 6 patients with alcohol intolerance and ethanol was used for 16 patients without alcohol intolerance.The primary endpoint was the positive response rate(pain score decreased to≤3)on postoperative day 7.Secondary endpoints included the time to onset of pain relief,duration of pain relief,and complication rates.RESULTS:There was no significant difference in the positive response rate on day 7.The rates were 83%and 69%in the phenol and ethanol groups,respectively.Regarding the time to onset of pain relief,in the phenol group,the median pre-treatment pain score was 5,whereas the post-treatment scores decreased to 1.5,1.5,and 1.5 at 2,8,and 24 h,respectively(P<0.05).In the ethanol group,the median pre-treatment pain score was 5.5,whereas the post-treatment scores significantly decreased to 2.5,2.5,and 2.5 at 2,8,and24 h,respectively(P<0.01).There was no significant difference in the duration of pain relief between the phenol and ethanol groups.No significant difference was found in the rate of complications between the 2groups;however,burning pain and inebriation occurred only in the ethanol group.CONCLUSION:Phenol had similar pain-relieving effects to ethanol in EUS-CPN.Comparing the incidences of inebriation and burning pain,phenol may be superior to ethanol in EUS-CPN procedures. AIM: To investigate the effectiveness of phenol for the relief of cancer pain by endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN). METHODS: Twenty-two patients referred to our hospital with cancer pain from August 2009 to July 2011 for EUS-CPN were enrolled in this study. Phenol was used for 6 patients with alcohol intolerance and ethanol was used for 16 patients without alcohol intolerance.The primary endpoint was the positive response rate (pain score decreased to≤3) on postoperative day 7.Secondary endpoints included the time to onset of pain relief, duration of pain relief, and complication rates .RESULTS: There was no significant difference in the positive response rate on day 7.The rates were 83% and 69% in the phenol and ethanol groups, respectively. Regarding the time to onset of pain relief, in the phenol group, the median pre-treatment pain score was 5, while the post-treatment scores decreased to 1.5, 1.5, and 1.5 at 2,8, and 24 h, respectively <0.05) .In the ethanol group, the m edian pre-treatment pain score was 5.5, whereas the post-treatment scores were significantly decreased to 2.5, 2.5, and 2.5 at 2,8, and 24 h, respectively (P <0.01). There was no significant difference in the duration of pain relief Between the phenol and ethanol groups. No significant difference was found in the rate of complications between the 2groups; however, burning pain and inebriation occurred only in the ethanol group. CONCLUSION: Phenol had similar pain-relieving effects to ethanol in EUS-CPN. Comparing the incidences of inebriation and burning pain, phenol may be superior to ethanol in EUS-CPN procedures.