By, Dr. Mukul Gharote, Oncology
Though not everyone suffering from cancer experiences pain, a majority of them experience pain at some part of the time or another. The amount of pain felt by a patient depends on the type of cancer, its stage and the pain threshold of the person. In many cases, cancer pain is manageable through drugs and other measures. Pain control forms an essential part of cancer therapy as it improves the quality of life of a patient.
Causes of cancer pain:
- Tumor mass pressing on the nerves, organs or bone.
- Most cancer treatments- radiotherapy, chemotherapy or surgery can lead to pain.
- Tests and procedures used for diagnosis and staging of cancer.
Types of cancer pain
- Nociceptive pain: It occurs due to damage or injury to the body, like during biopsy, invasion of tumor into the bones. These respond well to non- steroidal anti-inflammatory (NSAIDS) or opioids.
- Neuropathic pain: It occurs due injury to the nervous system. Difficult to treat, tricyclic antidepressants, antiepileptic drugs are used to relieve pain.
Management of cancer pain
Depending on the severity and type of cancer pain, several options exist.
- Drug therapy
- Mild to moderate pain
- NSAIDs like Acetaminophen, aspirin, ibuprofen. NSAIDs are potent analgesics and anti-inflammatory agents, helpful in relieving cancer pain of musculoskeletal origin. They are not used in patients’ experiencing nausea and vomiting after receiving chemotherapy and patients with a history of GI bleeding in the past. NSAIDs are over-the-counter drugs but should be taken only on the prescription of the doctor.
- Moderate to severe pain
- Non-opioid analgesic is beneficial in patients who do not respond adequately to NSAIDs and want to delay taking opioids. Patients on long-term tramadol therapy have reduced instances of respiratory depression, dependence and other side effects of opioids.
- Opioids are the most commonly used analgesics in the treatment of cancer pain. Codeine, Hydrocodone are mild opioids with the 1/10th potency of morphine, these are useful in moderate cancer pain. Oral formulations of Morphine are the first choice for severe chronic cancer pain. If a patient fails to respond to morphine drugs like Hydromorphone, Fentanyl, Oxycodone may be used. All these drugs have side effects like nausea, vomiting, constipation, drowsiness, cognitive impairment (mild).
- Adjuvant analgesics are medicines whose primary function is not pain relief but can be used for pain control in several conditions. For example:
- Tricyclic antidepressants and anti-epileptics can be used in case of cancer pain of neurogenic origin and for their positive effects on mood and sleep.
- Corticosteroids are used as adjuvant analgesics in bone pain, neuropathic pain due to compression of neural structures, headache caused by increased intracranial pressure, arthralgias.
- Mild to moderate pain
- Other modalities
- Nerve blocks around a nerve or spine, radiofrequency ablations.
- Physical therapy and rehabilitation.
- Imagery, biofeedback and relaxation techniques.