A validation study of the WHO method for cancer pain relief.

The method for cancer pain relief proposed by the World Health Organization (WHO) consists of guidelines for a three-step treatment, from non-opioids to weak and then strong opioids, according to need. Adjuvant drugs can be added to each step. This report presents the 2-year experience of the WHO Collaborating Centre at the National Cancer Institute of Milan in the use of this method. This retrospective study shows that a correct use of the analgesic ladder can reduce pain to a third of its initial intensity. The use of non-opioids had an average duration of 19.2 days; in 52% of the cases treatment was discontinued due to inefficacy and in 42%, to side effects. Weak opioids were administered on an average for 28.0 days. A shift to Strong opioids was made in 92% of the cases due to inefficacy and in 8% because of side effects. Treatment with strong opioids lasted for an average of 46.6 days and can be considered the mainstay of cancer pain therapy. Performance status was not altered considerably during the study and hours of sleep were doubled. The analgesic ladder proved efficacious in 71% of the cases. Neurolytic procedures had to be used in 29%. The authors conclude that analgesics, as proposed by WHO, are the most suitable treatment arm in controlling pain in palliative treatment for advanced cancer patients. Lack of availability or underuse of opioids constitute the real obstacle to the application of this method.