PHYSIOPATHOLOGY OF PAIN IN PC(pancreatic)

Pain in PC may be the result of three components: Visceral(内臓), somatic(related to the body), and neuropathic pain(神経). Visceral nociceptive influxes are produced by ductal obstruction, damage and inflammation in the upper abdominal viscera. Somatic pain is caused by cancer extension into the peritoneum(腹膜)and bones. The signals reach the celiac plexus nerves, at T12-L1 vertebral levels, via the sympathetic system. Primary sensory neurons involved in pain sensation release predominantly substance P and glutamate in the dorsal horn of the spinal cord. From there, they synapse through the splanchnic nerves with T5-T12 dorsal root ganglia, then to the central nervous system. The most characteristic aspect of pancreatic neoplasia is an extrapancreatic nerve plexus invasion, which consists of the first route of metastasis. This may explain the neuropathic pain sensation. Pour et al highlighted the histogenetic similarity between neuronal cells and the pancreatic cancer cells. The two types of cells may share identical growth factor receptors and surface adhesion molecules and have an affinity to neural tissues. Although PC cells damage nerves, several studies showed a harmony with cell-to-cell adhesion and migration of pancreatic cancer cells along the dorsal root ganglia neuritis inducing a mutual trophic nerve-cancer cell interaction[9-11]. Nerve cells neurotrophic factors and chemokines are capable of boosting PC cell invasiveness, multiplication, and locomotion. On the other hand, PC cells secrete neuromodulatory agents, which cause neuroplasticity and neuropathic pain. An increase of density of calcitonin gene-related peptide (CGRP) and tyrosine hydroxylase was noted, connoting a proliferation of nerve growth factors[12]. Studies have shown that growing sensory fibers are associated with necrotic damage of the nerve fiber endings and increased pain sensation[13].

analgesic noun /ˌænəlˈdʒiːzɪk/ (medical) ​a substance that reduces pain synonym painkiller

Oxycodone, sold under various brand names such as Roxicodone and OxyContin, is a semi-synthetic opioid used medically for treatment of moderate to severe pain. It is highly addictive and is a commonly abused drug. It is usually taken by mouth, and is available in immediate-release and controlled-release formulations.

Methadone, sold under the brand names Dolophine and Methadose among others, is a synthetic opioid agonist used for chronic pain and also for opioid use disorder. It is used to treat chronic pain, and it is also used to treat addiction to heroin or other opioids.

Hydromorphone, also known as dihydromorphinone, and sold under the brand name Dilaudid among others, is a morphinan opioid used to treat moderate to severe pain. Typically, long-term use is only recommended for pain due to cancer. It may be used by mouth or by injection into a vein, muscle, or under the skin.

Fentanyl Transdermal Patch 止痛吩坦尼貼片用藥

A more comprehensive oncologic pain management guideline was put forth by the National Comprehensive Cancer Network (NCCN) [10] and is discussed in greater detail below. They systematically target therapy to those patients who are opioid naïve, opioid tolerant, and who require ongoing care. They also take into account procedure-related pain and anxiety, neuropathic pain, treatment of side effects from narcotics, and the use of non-pharmacologic therapies. Patients at all pain levels are recommended to receive psychological support, education, non-pharmacologic interventions, e.g., heat/ice, massage, cognitive behavioral therapy, or relaxation training; and treatment of side effects from pharmacotherapy.

Oncology is a branch of medicine that deals with the study, treatment, diagnosis, and prevention of cancer. A medical professional who practices oncology is an oncologist. The name's etymological origin is the Greek word ὄγκος, meaning "tumor", "volume" or "mass".

[10] National Comprehensive Cancer Network, Adult Cancer Pain Guidelines Available online: http://www.nccn.org/professionals/physician_gls/PDF/pain.pdf (accessed on 12 November 2010)

Pharmacotherapy, also known as pharmacological therapy or drug therapy, is defined as medical treatment that utilizes one or more pharmaceutical drugs to improve ongoing symptoms (symptomatic relief), treat the underlying condition, or act as a prevention for other diseases (prophylaxis).