RCT Comparing the Analgesic Efficacy of 4 Therapeutic Strategies Based on 4 Different Major Opioids (Fentanyl, Oxycodone, Buprenorphine vs Morphine) in Cancer Patients With Moderate/Severe Pain, at the Moment of Starting 3rd Step of WHO Analgesic Ladder.

Pain, in neoplastic disease, is a symptom with severe negative impact on the quality of life of patients and a high incidence, with values around 70-90% in advanced and metastatic stages. Than 20 years the main reference for the pharmacological treatment of cancer pain are the guidelines produced by the World Health Organization (WHO). This document shows that the use of opioid drugs is the mainstay of treatment, with particular reference to opioids "major" (3 rd step of the analgesic ladder). The 4 opioids more most commonly prescribed in Italy (oral morphine and oxycodone, fentanyl and buprenorphine transdermal), based on the data currently available, have an analgesic effect would partly overlap but with different percentages of non-responders (NR), a different need to increase the dose over time to maintain adequate analgesia, a different action to the switch to another molecule for ineffectiveness analgesic. The observations described suggest that opioids, although they belong to the same family drug may not be fully comparable with regard to the clinical effects products. Important differences are known on the pharmacokinetic and pharmacodynamic and, more recently, also in terms of pharmacogenomics. This is a comparative study of analgesic strategies based on the use of the 4 mentioned opioids, going to look for possible differences in terms of analgesic efficacy, changes in dose over time, use of switch or permanent abandonment of treatment, parallel to the contour of the side effects. The associated sub-project will link the structure gene of patients and clinical results have emerged.