Abstract
Introduction The majority of cancer patients experience pain during the course of their disease, especially in the advanced stages. Pain may be directly related to tumor or result from cancer therapy. Unrelieved pain impairs functional status, compromises quality of life, and may interfere with antineoplastic treatment. The World Health Organization (WHO) has stated that relief of pain and other symptoms should be of high priority in the care of cancer patients (1,2). The WHO three-step analgesic ladder is a medication titration protocol that has been demonstrated to be effective in relieving 75-90% of cancer pain (3-5). Yet many cancer patients suffer with unrelieved pain due to a number of factors. Poor assessment of pain (6,7), professional knowledge deficits, and regulatory interference with the prescription of opioid analgesics (8) all contribute to the problem. Much progress has been made to overcome these educational and social barriers.