Treatment of cancer pain: Spanish Society of Medical Oncology (SEOM) recommendations for clinical practice.

Cancer pain should be controlled in most patients, however this is not always achieved. These guidelines describe the classification, evaluation and treatment of chronic cancer pain in accordance with the WHO treatment strategy of pain stages: mild, moderate and severe. For treatment during the third stage, we cover titration and rotation of opioids, as well as their side effects and prevention. Also described is neuropathic pain and refractory pain, coadjuvant treatments and non pharmacological analgesic treatments. Finally, treatment of breakthrough pain is defined.