Cancer pain can be managed effectively in most patients with cancer or with a history of cancer. Although cancer pain cannot always be relieved completely, therapy can lessen pain in most patients. Pain management improves the patient's quality of life throughout all stages of the disease.
Flexibility is important in managing cancer pain. As patients vary in diagnosis, stage of disease, responses to pain and treatments, and personal likes and dislikes, management of cancer pain must be individualized. Patients, their families, and their health care providers must work together closely to manage a patient's pain effectively.
To treat pain, it must be measured. The patient and the doctor should measure pain levels at regular intervals after starting cancer treatment, at each new report of pain, and after starting any type of treatment for pain. The cause of the pain must be identified and treated promptly.
To help the health care provider determine the type and extent of the pain, cancer patients can describe the location and intensity of their pain, any aggravating or relieving factors, and their goals for pain control. The family/caregiver may be asked to report for a patient who has communication problems such as a speech, language, or thinking impairment.
- Pain: The patient can describe the pain, when it started, how long it lasts, and whether it is worse during certain times of the day or night.
- Location: The patient can show exactly where the pain is on his or her body or on a drawing of a body and where the pain goes if it travels.
- Intensity or severity: The patient can keep a diary of the degree or severity of pain.
- Aggravating and relieving factors: The patient can identify factors that increase or decrease the pain.
- Behavioral response to pain: The health care provider and/or caregivers can note behaviors that may suggest pain in patients who have communication problems.
- Goals for pain control: With the health care provider, the patient can decide how much pain he or she can tolerate and how much improvement he or she may achieve. The patient can use a daily pain diary to increase awareness of pain, gain a sense of control of the pain, and receive guidance from health care providers on ways to manage the pain.
Assessment of the Outcomes of Pain Management
The results of pain management should be measured by monitoring for a decrease in the severity of pain and improvement in thinking ability, emotional well being, and social functioning. The results of taking pain medication should also be monitored. Drug addiction is rare in cancer patients. Developing a higher tolerance for a drug and becoming physically dependent on the drug for pain relief does not mean that the patient is addicted. Patients should take pain medication as prescribed by the doctor. Patients who have a history of drug abuse may tolerate higher doses of medication to control pain.
The World Health Organization (WHO) developed a 3-step approach for pain management based on the severity of the pain:
- For mild to moderate pain, the doctor may prescribe a Step 1 pain medication such as aspirin, acetaminophen, or a nonsteroidal anti-inflammatory drug (NSAID). Patients should be monitored for side effects, especially those caused by NSAIDs such as kidney or stomach and intestinal problems.
- When pain lasts or increases, the doctor may change the prescription to a Step 2 or Step 3 pain medication. Most patients with cancer-related pain will need a Step 2 or Step 3 medication. The doctor may skip Step 1 medications if the patient initially has moderate to severe pain.
- At each step the doctor may prescribe additional drugs or treatments (for example, radiation therapy).
- The patient should take doses regularly, "by mouth, by the clock" (at scheduled times), to maintain a constant level of the drug in the body; this will help prevent recurrence of pain. If the patient is unable to swallow, the drugs are given by other routes (for example, by infusion or injection).
- The doctor may prescribe additional doses of drug that can be taken as needed for pain that occurs between scheduled doses of drug.
- The doctor will adjust the pain medication regimen for each patient's individual circumstances and physical condition.
Acetaminophen and NSAIDs
NSAIDs are effective for relief of mild pain. They may be given with opioids for the relief of moderate to severe pain. Acetaminophen also relieves pain, although it does not have the anti-inflammatory effect that aspirin and NSAIDs do. Patients, especially older patients, who are taking acetaminophen or NSAIDs should be closely monitored for side effects.
Opioids are very effective for the relief of moderate to severe pain. Under treatment results when concerns about addiction (psychological dependence) to these drugs is confused with tolerance and physical dependence. Many patients with cancer pain become tolerant to opioids during long-term therapy. Therefore, increasing doses are necessary to continue to relieve pain, even at the risk of side effects.
There are several types of opioids. Morphine is the most commonly used opioid in cancer pain management. Other commonly used opioids include hydromorphone, oxycodone, methadone, and fentanyl. The availability of several different opioids allows the doctor flexibility in prescribing a medication regimen that will meet individual patient needs.
Other Drugs Used With Pain Medications
Other drugs may be given at the same time as the pain medication. This is done to increase the effectiveness of the pain medication, treat symptoms, and relieve specific types of pain. These drugs include antidepressants, anticonvulsants, local anesthetics, corticosteroids, and stimulants. There are great differences in how patients respond to these drugs. Side effects are common and should be reported to the doctor.
Drugs Used With Physical and Psychosocial Interventions
Noninvasive physical and psychological methods can be used along with drugs and other treatments to manage pain during all phases of cancer treatment. The effectiveness of the pain interventions depends on the patient's participation in treatment and his or her ability to tell the health care provider which methods work best to relieve pain.
Management With Alternative Therapies
Weakness, muscle wasting, and muscle/bone pain may be treated with heat (hot pack or heating pad); cold (flexible ice packs); massage, pressure, and vibration (to improve relaxation); exercise (to strengthen weak muscles, loosen stiff joints, help restore coordination and balance, and strengthen the heart); changing the position of the patient; restricting the movement of painful areas or broken bones; stimulation; controlled low-voltage electrical stimulation; or acupuncture.
Thinking and Behavioral Interventions
Thinking and behavior interventions are also important in treating pain. These interventions help give patients a sense of control and help them develop coping skills to deal with the disease and its symptoms. Beginning these interventions early in the course of the disease is useful so that patients can learn and practice the skills while they have enough strength and energy. Several methods should be tried, and one or more should be used regularly.
- Relaxation and imagery: Simple relaxation techniques may be used for episodes of brief pain (for example, during cancer treatment procedures). Brief, simple techniques are suitable for periods when the patient's ability to concentrate is limited by severe pain, high anxiety, or fatigue. (See Relaxation exercises below)
- Hypnosis: Hypnotic techniques may be used to encourage relaxation and may be combined with other thinking/behavior methods. Hypnosis is effective in relieving pain in people who are able to concentrate and use imagery and who are willing to practice the technique.
- Redirecting thinking: Focusing attention on triggers other than pain or negative emotions that come with pain may involve distractions that are internal (for example, counting, praying, or saying things like "I can cope") or external (for example, music, television, talking, listening to someone read, or looking at something specific). Patients can also learn to monitor and evaluate negative thoughts and replace them with more positive thoughts and images.
- Patient education: Health care providers can give patients information and instructions about pain and pain management and assure them that most pain can be controlled effectively. Health care providers should also discuss the major barriers that interfere with effective pain management.
- Psychological support: Short-term psychological therapy helps some patients. Patients who develop clinical depression or adjustment disorder may see a psychiatrist for diagnosis.
- Support groups and religious counseling: Support groups help many patients. Religious counseling may also help by providing spiritual care and social support.
Local or whole-body radiation therapy may increase the effectiveness of pain medication and other noninvasive therapies by directly affecting the cause of the pain (for example, by reducing tumor size). A single injection of a radioactive agent may relieve pain when cancer spreads extensively to the bones.
Surgery may be used to remove part or all of a tumor to reduce pain directly, relieve symptoms of obstruction or compression, and improve outcome, even increasing long-term survival.
Less invasive methods should be used for relieving pain before trying invasive treatment, however, some patients may need this type of therapy.
A nerve block is the injection of either a local anesthetic or a drug that inactivates nerves to control otherwise uncontrollable pain. Nerve blocks can be used to determine the source of pain, to treat painful conditions that respond to nerve blocks, to predict how the pain will respond to long-term treatments, and to prevent pain following procedures.
Surgery can be performed to implant devices that deliver drugs or electrically stimulate the nerves. In rare cases, surgery may be done to destroy a nerve or nerves that are part of the pain pathway.
Management of Procedural Pain
Many diagnostic and treatment procedures are painful. Pain related to procedures may be treated before it occurs. Local anesthetics and short-acting opioids can be used to manage procedure-related pain, if enough time is allowed for the drug to work. Anti-anxiety drugs and sedatives may be used to reduce anxiety or to sedate the patient. Treatments such as imagery or relaxation are useful in managing procedure-related pain and anxiety.
Patients usually tolerate procedures better when they know what to expect. Having a relative or friend stay with the patient during the procedure may help reduce anxiety. Patients and family members should receive written instructions for managing the pain at home. They should receive information regarding whom to contact for questions related to pain management.
Treating Elderly Patients
Older patients are at risk for under-treatment of pain because their sensitivity to pain may be underestimated, they may be expected to tolerate pain well, and misconceptions may exist about their ability to benefit from opioids. Issues in assessing and treating cancer pain in older patients include the following:
- Multiple chronic diseases and sources of pain: Age and complicated medication regimens put older patients at increased risk for interactions between drugs and between drugs and the chronic diseases.
- Visual, hearing, movement, and thinking impairments may require simpler tests and more frequent monitoring to determine the extent of pain in the older patient.
- Nonsteroidal anti-inflammatory drug (NSAID) side effects, such as stomach and kidney toxicity, thinking problems, constipation, and headaches, are more likely to occur in older patients.
- Opioid effectiveness: Older patients may be more sensitive to the pain-relieving and central nervous system effects of opioids resulting in longer periods of pain relief.
- Patient-controlled analgesia must be used cautiously in older patients, since drugs are slower to leave the body and older patients are more sensitive to the side effects.
- Other methods of administration, such as rectal administration, may not be useful in older patients since they may be physically unable to insert the medication.
- Pain control after surgery requires frequent direct contact with health care providers to monitor pain management.
Reassessment of pain management and required changes should be made whenever the older patient moves (for example, from hospital to home or nursing home).