Role of Implantable Intrathecal Pumps in Refractory Cancer Pain: Systematic Review and Meta-Analysis

Despite advances in systemic analgesic strategies for cancer patients suffering pain, a subset of patients remains unresponsive to standard treatment. Intrathecal infusion therapy offers targeted pain relief, with implantable pumps being particularly beneficial for those with longer life expectancies. Although recommended in clinical guidelines, implantable pumps remain underused. To support informed clinical decision-making, we conducted a systematic review and meta-analysis to evaluate the efficacy of this therapy in reducing refractory cancer-related pain.

This systematic review and meta-analysis followed the PRISMA guideline. We searched PubMed, Cochrane, BVS Lilacs, and Epistemonikos for cancer-related pain management using an intrathecal infusion system with an implantable pump and a follow-up of at least three months. The risk of bias was assessed using RoB-2 and ROBINS-I tools. Data extracted included pain intensity, adverse events and quality of life.

Twelve articles were included: two randomized controlled trials and ten single-arm studies. Our meta-analysis of pain reduction found that mean pain intensity decreased by 4.37 points (95% CI -4.89 to -3.84) after three months of implantation, and by 3.30 (95% CI -5.49 to -1.12) after six months. The most frequently reported adverse events were postdural headache, nausea and vomiting. Although quality of life improved, further studies are needed for a comprehensive evaluation.

Implantable intrathecal infusion systems seem to be a viable alternative to manage refractory cancer-related pain; however, these findings should be interpreted carefully given the methodological limitations, including the lack of comparative design and the high risk of bias in the included studies.