Cancer pain management: Part II: Interventional techniques

The WHO analgesic ladder, with its emphasis on ‘by the clock’ oral analgesia, forms a useful framework for the initial pharmacological management of patients with cancer pain. It is reported to be successful in 80–90% of patients. However, of the 10–20% of patients with pain that is poorly responsive to opioids, or where side-effects are particularly problematic, some may greatly benefit from invasive procedures designed to interrupt pain signals along neural pathways from periphery to the brain. It should be emphasized that such procedures should not be seen as the ‘4th step’ of the WHO analgesic ladder, but can and should be considered at each step depending on patient preference and need. There is opportunity to interrupt nocioceptive traffic at peripheral and central levels via destructive neuroablatory or non-destructive techniques. All interventions designed to relieve cancer pain carry attendant risk, and these must be weighed against potential benefits on a case-by-case basis. Overall, 8% of patients with cancer pain may require nerve blocks, 3% neurolytic blocks, and 3% neuraxial techniques.