The Role of Central Sensitization in Pain, Functionality, and Quality of Life in Cancer Patients

Pain is one of the most important and challenging symptoms in cancer patients. Depending on the stage of cancer, approximately 40% to 70% of patients complain of pain. With the increasing lifespan of cancer patients due to developing treatments, pain palliation has become even more crucial to improve their quality of life. Cancer-related pain can develop through multiple mechanisms such as the tumor itself, metastasis, or the methods used in treatment. The type of pain can be nociceptive, neuropathic, or mixed. Central sensitization refers to the increased response of central nervous system nociceptive neurons to normal or subthreshold stimuli. Recently, central sensitization (CS) has been recognized as a potential pathophysiological mechanism underlying a group of chronic pain diseases such as fibromyalgia, temporomandibular joint disorder, irritable bowel syndrome, interstitial cystitis, tension-type headache, and chronic low back pain. Since pain perception varies from person to person, physicians should assess the character of pain thoroughly and not rely solely on peripheral pain treatment in cases with a component of central sensitization. The lack of evaluation of the extent to which central sensitization affects patients and the failure to fully determine the factors influencing it appear to be clinical limitations for now. There are studies suggesting that central sensitization may be a significant factor in chronic refractory pain in cancer patients, indicating the need for consideration of alternative options to classical treatments. To the best of our knowledge, no study has been conducted in Turkey to investigate the frequency of central sensitization and its impact on treatment outcomes in chronic cancer pain patients visiting outpatient clinics. The aim of this study is to investigate the frequency of central sensitization and its effect on pain and quality of life in chronic cancer pain patients attending algology clinics in multiple centers in Turkey.