Pain therapy.

Cancer-related pain is a major issue of healthcare systems worldwide. The reported incidence, considering all stages of the disease, is 51%, which can increase to 74% in the advanced and terminal stages. For advanced cancer, pain is moderate to severe in about 40-50% and very severe or excruciating in 25-30% of cases. Pain is both a sensation and an emotional experience. Pain is always subjective; and may be affected by emotional, social and spiritual components thus it has been defined as "total pain". From a pathophysiological point of view, pain can be classified as nociceptive (somatic and visceral), neuropathic (central, peripheral, sympathetic) idiopathic or psychogenic. A proper pain assessment is fundamental for an effective and individualised treatment. In 1986 the World Health Organisation (WHO) published analgesic guidelines for the treatment of cancer pain based on a three-step ladder and practical recommendations. These guidelines serve as an algorithm for a sequential pharmacological approach to treatment according to the intensity of pain as reported by the patient. The WHO analgesic ladder remains the clinical model for pain therapy. Its clinical application should be employed only after a complete and comprehensive assessment and evaluation based on the needs of each patient. When applying the WHO guidelines, up to 90% of patients can find relief regardless of the settings of care, social and/or cultural environment. This is the standard treatment on a type C basis. Only when such an approach is ineffective are interventions such as spinal administration of opioid analgesics or neuroinvasive procedures recommended.