Effectiveness of Superior Hypogastric Plexus Neurolysis for Pelvic Cancer Pain.

Background: The superior hypogastric plexus block has been indicated for visceral pelvic pain treatment associated with malignancy. The first international report of this technique was published by Plancarte et al, in which a posterior percutaneous approach guided by fluoroscopy was described by applying neurolytic agents. The considerable variability in the data reported gave rise to 2 clinical approaches to those who performed the blockade early and those who executed it at a later stage of cancer.

Objectives: The present study aims to provide more evidence regarding the effectiveness of this procedure.

Study Design: This is a retrospective, longitudinal, descriptive study.

Setting: The study was held at the pain unit service of the National Cancer Institute, Mexico City.

Methods: A nonprobabilistic sample was selected; the data collection took place from January 2006 to December 2016 with patients diagnosed with pelvic pain, confirmed by imaging and biopsy studies. Patients who received any other type of intervention of the sympathetic axis, patients with a different approach than the classic or paravertebral technique, and patients with low survival rate were excluded. The Student t test was used to measure the significant difference between Visual Analog Scale (VAS) and morphine equivalent daily dose. The Cochran-Mantel-Haenszel test and the Gamma test were used to measure the association between the initial Karnofsky and blockade success.

Results: The study included a total of 180 patients. The success rate was 59.4% at 1 month, 55.5% at 3 months, and 48.8% at 6 months. There was a sustained and significant VAS reduction that was 49.55% at 3 months. A significant reduction in opioid consumption of 12.55% was found at 3 months. There was no significant statistical evidence related to either opioid consumption or the functionality of the patient before the blockade as an influential variable in the success of the procedure.

Limitations: Retrospective study, developed in a single center.

Conclusions: Although opioids remain the cornerstone of cancer pain treatment, they produce many deleterious side effects. The superior hypogastric plexus neurolysis represents a reproducible and effective alternative in the management of pain in this group of patients.

Key Words: Pelvic pain, neoplasms, chemical neurolysis, pain management, cancer pain, palliative care, analgesia, nerve block.