Phenol-based endoscopic ultrasound-guided celiac plexus neurolysis for East Asian alcohol-intolerant upper gastrointestinal cancer patients: a pilot study.

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, 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, 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 2 groups; 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.