Predictors of analgesic efficacy of neurolytic celiac plexus block in patients with unresectable pancreatic cancer: the importance of timing

Background Neurolytic celiac plexus block (NCPB) is a safe and effective method for reducing abdominal cancer pain. However, the analgesic efficacy of NCPB is not always guaranteed. The aim of this retrospective study was to identify predictors for the analgesic efficacy of NCPB in patients with unresectable pancreatic cancer. Methods Patients with unresectable pancreatic cancer who underwent NCPB from 2006 to 2015 were enrolled. Good analgesia after NCPB was defined as ≥ 50% reduction in pain score at day 30. Patient demographics, cancer characteristics, and pain-related factors were evaluated using a logistic regression analysis to identify predictors for good analgesia after NCPB. Additionally, survival outcomes were compared between patients with poor and good analgesia after NCPB. Results A total of 112 patients satisfied the study protocol requirements. Forty-seven patients (41.9%) showed good analgesia after NCPB. Better performance status, lower serum CA 19-9 level, shorter pain duration, and lower opioid dose were observed in patients with good analgesia after NCPB. Good performance status (ECOG performance status 1 vs. 2 or 3, OR = 2.737, 95% CI = 1.149 to 6.518, P = 0.023) and low daily opioid use (< 150 vs. ≥ 150 mg, OR = 2.813, 95% CI = 1.159 to 6.831, P = 0.022) before NCPB were independent predictors of good analgesia after NCPB. The median survival was significantly lower for patients with poor analgesia after NCPB (68 vs. 150 days, P < 0.001). Conclusion NCPB should be offered early to selected patients to improve its analgesic efficacy in advance of deterioration from disease and pain in this population.