Recent progress in the pharmacotherapy of cancer pain.

Cancer pain can be relatively well managed with primary therapies, according to the WHO ladder. However, different conditions may limit the response to the analgesic drug used, which are mainly oploids. Specifically, adverse effects may prevail against the analgesic activity in the clinical setting. New pharmacological strategies may enable a more satisfactory response to be obtained, in terms of balance between analgesia and adverse effects. The change of route of administration or the use of alternative opioids is a first-line option. The use of adjuvant drugs may also improve analgesia with different mechanisms. Recent studies have demonstrated the value of these alternative approaches. However, most of them require definite confirmation in specific well-designed studies.