Cancer pain
Pain in cancer may arise from a tumor compressing or infiltrating nearby body parts; from treatments and diagnostic procedures; or from skin, nerve and other changes caused by a hormone imbalance or immune response.
Objective psychological testing has found problems with memory, attention, verbal ability, mental flexibility and thinking speed.
For example, it is possible through psychosurgery and some drug treatments, or by suggestion (as in hypnosis and placebo), to reduce or eliminate the unpleasantness of pain without affecting its intensity.
It is usually felt as tenderness, with constant background pain and instances of spontaneous or movement-related exacerbation, and is frequently described as severe.
[19][20] When tumors compress, invade or inflame parts of the nervous system (such as the brain, spinal cord, nerves, ganglia or plexa), they can cause pain and other symptoms.
It may appear at the site of the cancer but it frequently radiates diffusely to the upper thigh, and may refer to the lower back, the external genitalia or perineum.
Another report described seven people with cancer, whose previously well-controlled pain escalated significantly over several days.
[30] Certain sociodemographic characteristics have also been shown to disproportionately affect the types of people who are more likely to experience mental health issues due to cancer diagnoses.
[32] A person's adjustment to cancer depends vitally on the support of their family and other informal carers, but pain can seriously disrupt such interpersonal relationships, so people with cancer and therapists should consider involving family and other informal carers in expert, quality-controlled psychosocial therapeutic interventions.
[6] Then, if complete pain relief is not achieved or disease progression necessitates more aggressive treatment, mild opioids such as codeine, dextropropoxyphene, dihydrocodeine or tramadol are added to the existing non-opioid regime.
If the initial presentation is severe cancer pain, this stepping process should be skipped and a strong opioid should be started immediately in combination with a non-opioid analgesic.
[27] However, a 2017 Cochrane Review found that there is no high-quality evidence to support or refute the use of non-steroidal anti-inflammatories (NSAIDs) alone or in combination with opioids for the three steps of the three-step WHO cancer pain ladder and that there is very low-quality evidence that some people with moderate or severe cancer pain can obtain substantial levels of benefit within one or two weeks.
Antiemetic and laxative treatment should be commenced concurrently with strong opioids, to counteract the usual nausea and constipation.
Other delivery routes such as sublingual, topical, transdermal, parenteral, rectal or spinal should be considered if the need is urgent, or in case of vomiting, impaired swallow, obstruction of the gastrointestinal tract, poor absorption or coma.
[27] Current evidence for the effectiveness of fentanyl transdermal patches in controlling chronic cancer pain is weak, but they may reduce complaints of constipation compared with oral morphine.
[42] Since anxiolytics such as benzodiazepines and major tranquilizers add to sedation, they should only be used to address anxiety, depression, disturbed sleep or muscle spasm.
[43] Radiotherapy is used when drug treatment is failing to control the pain of a growing tumor, such as in bone metastasis (most commonly), penetration of soft tissue, or compression of sensory nerves.
Often, low doses are adequate to produce analgesia, thought to be due to reduction in pressure or, possibly, interference with the tumor's production of pain-promoting chemicals.
[43] A neurolytic block is the deliberate injury of a nerve by the application of chemicals (in which case the procedure is called "neurolysis") or physical agents such as freezing or heating ("neurotomy").
[43] Though the neurolytic block lacks long-term outcome studies and evidence-based guidelines for its use, for people with progressive cancer and otherwise incurable pain, it can play an essential role.
Cutting through or removal of nerves (neurectomy) is used in people with cancer pain who have short life expectancy and who are unsuitable for drug therapy due to ineffectiveness or intolerance.
[47] Cordotomy involves cutting nerve fibers that run up the front/side (anterolateral) quadrant of the spinal cord, carrying heat and pain signals to the brain.
Pancoast tumor pain has been effectively treated with dorsal root entry zone lesioning (destruction of a region of the spinal cord where peripheral pain signals cross to spinal cord fibers); this is major surgery that carries the risk of significant neurological side effects.
First, the leads are implanted, guided by fluoroscopy and feedback from the patient, and the generator is worn externally for several days to assess efficacy.
People may be reluctant to take adequate pain medicine because they are unaware of their prognosis, or may be unwilling to accept their diagnosis.
[56] The right to adequate palliative care has been affirmed by the US Supreme Court in two cases, Vacco v. Quill and Washington v. Glucksberg, which were decided in 1997.
[58] The 1994 Medical Treatment Act of the Australian Capital Territory states that a "patient under the care of a health professional has a right to receive relief from pain and suffering to the maximum extent that is reasonable in the circumstances".
For instance, people who experience pain on movement may be willing to forgo strong opioids in order to enjoy alertness during their painless periods, whereas others would choose around-the-clock sedation so as to remain pain-free.
[8] Some patients – particularly those who are terminally ill – may not wish to be involved in making pain management decisions, and may delegate such choices to their treatment providers.
The patient's participation in their treatment is a right, not an obligation, and although reduced involvement may result in less-than-optimal pain management, such choices should be respected.
