The global experience of cancer pain.

Pain is a significant problem in patients with cancer. Pain occurs in approximately 50% of patients at some point during the disease process and in up to 75% of patients with advanced cancer. Total pain impacts quality of life domains including physical, psychological, social, and spiritual realms. Unfortunately, pain is underappreciated and undermanaged throughout the world. Lack of knowledge among healthcare professionals, inadequate pain assessment, fears of addiction, and beliefs that pain is an inevitable component of cancer are common barriers. Education about comprehensive pain assessment and optimal management strategies and discussions about belief systems regarding pain can assist to bridge the gap between suffering and comfort. Self-report is the gold standard for pain assessment. Gathering information about the location(s), intensity, quality and temporal factors is essential. Intensity should be quantified on a rating scale to determine the amount of pain and the degree of relief from interventions. Quality can be used to diagnose the specific pain syndrome. Temporal factors provide input about how the pain is experienced over time and can offer input into the pain management plan of care. For patients who cannot self-report pain, non-verbal assessment tools are available to aid in assessment. The World Health Organization's Analgesic Ladder provides a template for the management of cancer pain. For step 1, pain can be managed with nonsteroidal anti-inflammatory drugs (NSAIDS) and other nonopioid analgesics. As pain persists or increases, step 2 involves managing pain with select opioids for mild to moderate pain along with NSAIDS and nonopioid analgesics. Step 3 of the ladder is applicable to many cancer pain syndromes, and includes opioids for moderate to severe pain in conjunction with NSAIDS and nonopioids. This 3 step approach can be 80-90% effective. This polypharmaceutical employed with behavioral complimentary techniques are often employed to interrupt pain along the physiological pathways during transduction, transmission, perception, and modulation. Severe cancer pain that is not managed with the Step 3 approach, deserves special attention and unique strategies for control. When pain control is inadequate or if side effects are intolerable, a change of opioid or a change in the route of administration is recommended. Intraspinal analgesics can be trialed in patients who have intractable pain or intolerable side effects with systemic opioids. This route is especially helpful in neuropathic pain syndromes located at the trunk level or below. Opioid doses in all patients with intractable pain should be titrated judiciously for optimal relief with a balance of toxicity management. Other strategies for intractable pain should be investigated including nerve blocks and neuroablation. The overall goal for patients is to attain comfort with minimal side effects and optimal quality of life.