Continuous intrathecal therapy for refractory cancer pain: A systematic review and meta-analysis focusing on partially implanted devices.

CONTEXT: Conventional pain therapies sometimes fail in patients with severe neuropathic pain or bone metastases. Intrathecal therapy provides an alternative but is resource-intensive, technically demanding and costly.

OBJECTIVE

To compare the advantages and limitations of partially implanted devices (PIDs) versus conventional medical management or totally implanted devices (TIDs) in adults with cancer-related pain.

METHODS

A systematic literature review up to September 2024 was conducted, with an updated search performed in August 2026. Eligible studies included those on adults with refractory cancer pain receiving PID intrathecal therapy compared with conventional therapy, and comparative studies evaluating PIDs versus TIDs. Pain intensity was analysed using a meta-analysis; a synthesis without meta-analysis was used for other outcomes.

RESULTS

Of the 1,102 records, 15 were included, evaluating pain intensity, systemic opioid dose, quality of life (QoL), depression/anxiety, functional capacity and complications in PID-treated patients. A meta-analysis of pain intensity at 4 weeks showed statistically significant reduction with intrathecal therapy, which also reduced opioid use and improved QoL. Complication rates were lower than in conventional therapy. Investigations of depression/anxiety and functional capacity were limited, with inconsistent findings. Certainty of evidence was moderate for pain intensity and QoL; low for opioid dose, depression/anxiety and complications; and very low for functional capacity.

CONCLUSIONS

Intrathecal therapy for refractory cancer pain with PIDs provides superior pain relief and improved QoL compared with the conventional therapy in patients with refractory cancer pain. Evidence for psychological and functional outcomes remains limited. Overall certainty of evidence is low to moderate, but findings support intrathecal therapy as a clinically meaningful option for selected patients.