Pathophysiology of Pain in Cancer

Question: Discuss about thePathophysiology of Pain in Cancer. Answer: Introduction If a patient suffers from cancer then pain can frequently occur. Some kinds of cancer are almost untreatable; however the pain can be treated according to patient satisfaction. Understanding the Pathophysiology of the cancer pain is important for carrying out pharmacological management of pain. The pain is a very disturbing sensory experience, which occurs due to destruction or damage in the tissue cells (Falk, and Dickenson, 2014). Destruction of the tissues can be called as tearing or ripping of that part of body. The intense pain is caused due to cancer. The humans, sense pain through the nervous system. At the end of every nerve in the skin, there is pain sensing structure is present. This is called as Nociceptors and this pain sensing structure is also present on bones, internal organs and connective tissues. The stimulus of the pain is modulated through various nerve systems. The sensations of the pain are sent to the spinal cord through two types of fibers, which are A delta fiber and C fiber (Webber et al, 2014). A delta fiber transfers the sensation of the pain very quickly, while the C fibers are considered to be unmyelinated and are slower in transferring the pain senses. The signals of the A delta fiber can be sensed immediately if any part of the body is hurt, but the adverse pain of the wound is sensed later, which is because of the C fiber. At the level of the synapses, variety of the neurotransmitters is responsible for modulating the pain. These neurotransmitters are noradrenaline, prostaglandins, substance P, endorphins, and enkephalins (von Gunten, 2011). The neurotransmitters remain active at the level of spinal cord, brain and nociceptor. The pain can become worse if some of the neurotransmitters amplify. Pain is mainly categorized in the two main categories; these categories are nociceptive and neuropathic. The Pathophysiology of the cancer pain can be affected by the physical findings, history and laboratory results of the patient. The pain associated with tumor is generally nonciceptive and that associated with injury of the neural tissues is neuropathic. Nociceptive Pain According to the study of von Gunten (2011) due to the stimulation of the nociceptor in the peripheral nervous system, results in the nociceptive pain. The pain is the result of tissue damage that has been caused due to chemical, mechanical and thermal stimuli. Some the core characteristics associated with this kind of pain are mediation of the pain through direct stimulation of the nociceptors. The transmission of this kind of pain takes the neural pathway that includes A delta fiber, C fiber, dorsal horn of the spinal cord and then towards brain. This kind of pain can be chonic as well as acute. This kind of pain is further sub divided in somatic and visceral pain, which is characterized by the location of presence of nociceptors. Nociceptive pain can be further subdivided into somatic and visceral pain based on the location of the nociceptors. This kind of pain occurs in the somatic nervous system of bones, muscles, skin and integuments. Visceral pain is characterized as the stimulation of the nociceptor occurs in the visceral organs of the body. The visceral organs include liver, intestine, spleen etc. According to pathophysioloy of thei kind of pain, the localizing the pain becomes difficult for the patient. According to Falk, S. and Dickenson (2014) It is very difficult to localize such kind of pain, this is because the autonomic nervous system is unmyelinated frequently and link in plexuses are highly crossed. Neuropathic Pain The Pathophysiology of the pain changes in Neuropathic pain, as the Pathophysiology changes to peripheral or central nervous system. The changes in the nervous system are caused due to various reaso9ns. The changes in the peripheral nervous system can be caused due to trauma of surgical operation, chemotherapy, and attempt of the nervous system tissue to regrow (Webber et al, 2014). The changes in the central nervous system are characterized by sensitization and also central pain syndrome. In comparison to nociceptive type of pains in cancer, neuropathic pain is difficult to be identified and pharmacological management of such pain becomes difficult. The changes in the peripheral system occur due the ectopic activity of the sodium channels. In addition to this condition, the stimulation of the excitatory amino acid pathways in the spinal cord also occur (Fallon, 2013). The nerves who are found to be involved in the neuropathic pain are highly damaged the abnormal functioning occur in the compensatory mechanism of the nervous system. This situation induces more painful situation for the individual suffering with cancer. Bibliography Fallon, M.T., 2013. Neuropathic pain in cancer.British journal of anaesthesia,111(1), pp.105-111. Falk, S. and Dickenson, A.H., 2014. Pain and nociception: mechanisms of cancer-induced bone pain.Journal of Clinical Oncology,32(16), pp.1647-1654. von Gunten, C.F., 2011. Pathophysiology of pain in cancer.Journal of pediatric hematology/oncology,33, pp.S12-S18. Webber, K., Davies, A.N., Zeppetella, G. and Cowie, M.R., 2014. Development and validation of the breakthrough pain assessment tool (BAT) in cancer patients.Journal of pain and symptom management,48(4), pp.619-631.