Pain in the cancer patient: different pain characteristics CHANGE pharmacological treatment requirements

Abstract

Twenty years ago, the main barriers to successful cancer pain management were poor assessment by physicians, and patients' reluctance to report pain and take opioids. Those barriers are almost exactly the same today. Cancer pain remains under-treated; in Europe, almost three-quarters of cancer patients experience pain, and almost a quarter of those with moderate to severe pain do not receive any analgesic medication. Yet it has been suggested that pain management could be improved simply by ensuring that every consultation includes the patient's rating of pain, that the physician pays attention to this rating, and a plan is agreed to increase analgesia when it is inadequate. After outlining current concepts of carcinogenesis in some detail, this paper describes different methods of classifying and diagnosing cancer pain and the extent of current under-treatment. Key points are made regarding cancer pain management. Firstly, the pain may be caused by multiple different mechanisms and therapy should reflect those underlying mechanisms -rather than being simply based on pain intensity as recommended by the WHO three-step ladder. Secondly, a multidisciplinary approach is required which combines both pharmacological and non-pharmacological treatment, such as psychotherapy, exercise therapy and electrostimulation. The choice of analgesic agent and its route of administration are considered, along with various interventional procedures and the requirements of palliative care. Special attention is paid to the treatment of breakthrough pain (particularly with fast-acting fentanyl formulations, which have pharmacokinetic profiles that closely match those of breakthrough pain episodes) and chemotherapyinduced neuropathic pain, which affects around one third of patients who receive chemotherapy. Finally, the point is made that medical education should place a greater emphasis on pain therapy, both at undergraduate and postgraduate level.

Canadian Recommendations for the Management of Breakthrough Cancer Pain

“…Pain is a common occurrence in patients with cancer and especially in those with advanced disease 1 . Cancer pain is multifactorial in nature and can be classified according to its pathophysiology (nociceptive, neuropathic), cause (related or unrelated to the disease and its treatment), and the timing of its occurrence 1,2 .…”

“…Cancer pain is multifactorial in nature and can be classified according to its pathophysiology (nociceptive, neuropathic), cause (related or unrelated to the disease and its treatment), and the timing of its occurrence 1,2 . Breakthrough pain represents a key element of pain management in patients with malignancies.…”

“…The manifestation of btcp is influenced by numerous patient-, cancer-, and treatment-related factors and changes throughout the course of the disease 1 . Factors directly related to cancer include compression or infiltration of hollow organs, soft tissue, bones, and nerves.…”

“…Causes indirectly related to cancer include the consequences of disease (coughing because of lung cancer, herpes zoster or post-herpetic neuralgia because of a compromised immune system, back pain because of immobility) or its treatment (investigational procedure, chemotherapy, radiation, surgery), or both. Pre-existing conditions or those that arise independently of cancer (arthritis, migraine) are recognized as a source of pain in 3% -10% of cancer patients 1 . Patient and physician attitudes toward the disease and its treatment can also contribute to breakthrough pain.…”

Change Pain: Ever Evolving—An Update for 2016

“…CHANGE PAIN suggests some simple guidance: cancer patients should have a validated pain assessment at every follow-up session, the clinical team should discuss pain with the patient during each and every session, and the oncologist should develop a plan to address the pain using evidence-based treatments, and refer the patient to a pain specialist if necessary [12]. …”