Splanchnic neurolysis for severe cancer pain caused by abdominal paraaortic lymph node metastasis

Noxious stimuli caused by enlarged metastatic para-abdominal aortic lymph nodes (PAN) enter the spinal cord via the sympathetic nervous system, and the pain is sometimes resistant to conventional pharmacotherapy. The aim of this retrospective clinical investigation was to verify the efficacy and safety of splanchnic nerve neurolysis (SNN) for intractable abdominal and/or back pain caused by enlarged PAN.

Among cancer pain patients referred to the Palliative Care Team in our hospital between April 2016 and November 2023, those who received SNN for pain relief, with abdominal and/or back pain due to PAN swelling which seemed to be a determining factor for opioid dosage, were all included. SNN was performed under X-ray fluoroscopy guidance in all the cases using a transdiscal approach through Th12/L1 or L1/2 intervertebral space.

Sixteen (6 male and 10 female) patients aged 55.1 ± 12.5 years were included. The major primary sites of malignancy were the esophagus, colon, rectum, and uterine cervix. The opioid doses (oral morphine equivalent) including rescue doses during the 24 h before, 1 week after, and 4 weeks after SNN were 427 ± 514.7, 267.1 ± 296.8 (p = 0.006), and 229.2 ± 230.9 (p = 0.035) mg/day, respectively. The numbers of rescue doses were 4.9 ± 3.0, 1.7 ± 2.6 (p = 0.003), and 2.3 ± 2.5 (p = 0.035) times/day, respectively. Both these parameters significantly decreased by SNN. Mild diarrhea for 2 to 3 days after SNN was observed in two patients.

These results suggest that SNN is an effective and safe interventional treatment for intractable abdominal and/or back pain caused by enlarged PAN.