Understanding Cancer-Related Pain

The prevalence of pain in patients with a cancer diagnosis is approximately 44.5%. (1) One study found that of those who experience pain, 67% found it distressing, 36% intolerable, and 32% reported that the pain “made them want to die”. (2,3) Thus, the prevalence of pain in cancer patients is high, and having pain sufficiently managed is important to their quality of life.

We know that pain can be acute or chronic, but it can also be broken down into neuropathic, nociceptive, musculoskeletal, inflammatory, psychogenic, or mechanical. All of these are possible with cancer-related pain. For example, acute pain may be directly related to cancer (i.e., pathological fracture, obstruction), a side effect of the treatment (i.e., mucositis, neuropathy), or co-medications (i.e., pegfilgrastim). Chronic pain is usually due to the tumor itself but can also be due to treatment, including chemotherapy, hormone therapy, radiation, surgery, or stem cell transplant.

Patients should be asked about pain, ongoing or new, at every visit, and the subjective sensation of pain should be documented using a visual tool, such as the Visual Analog Scale (VAS). This is important as pain is generally subjective and may vary between patients.  It is not uncommon for long-term pain sufferers to underestimate the toll pain may be taking on day-to-day activities. This may be because of fear of pain management prescriptions (such as opioids) and associated side effects from them. (4) Therefore, the practitioner should initiate this conversation.

Pain that is complex, ongoing, or poorly controlled should prompt a referral to a pain management specialist. Proper clinical assessment and imaging may help delineate the source of pain so that proper treatment can be determined. The American Society of Clinical Oncology (ASCO) published guidelines in 2016 for non-pharmacologic choices for providers to consider, such as physical medicine and rehabilitation, psychological approaches, or integrative therapies (acupuncture, massage). (5) These options may be considered in circumstances with mild pain or discomfort.

A stepwise approach is the most common strategy for pain management, such as the World Health Organization (WHO) analgesic ladder. (6) The principles of this approach include ensuring prescriptions are given orally around the clock rather than as needed. Additionally, the least harmful medications should be started first, such as a non-opioid, and gradually working up to strong opioid medication if a patient’s pain is persisting or increasing. And as always, a referral to pain management is crucial for any patient with uncontrolled pain.

For more information on pain control interventions, naturopathic treatments for pain, and prescription considerations for pain, consider the Advanced Integrative Oncology Palliative Care Course by the Integrative Oncology Institute.