Cancer-related pain is distinct from pain experienced by patients without malignancies. More than half of cancer patients experience cancer-related pain and it is one of the symptoms patients fear most.1 Unrelieved pain denies patients comfort and greatly affects their activities, motivation, interactions with family and friends, and overall quality of life.2
The mainstay cancer pain therapies are opioids, which come with concerning adverse effects. Constipation, nausea and vomiting, pruritus, delirium, respiratory depression, motor and cognitive impairment, and sedation are fairly common, especially when multiple agents are used.3 Refractory cancer pain treated with opioids may result in opioid-induced hyperalgesia. Paradoxically, exposure to opioids may increase patent sensitivity to pain.4 The administration of opioids and other medications by the intrathecal route with implantable pumps is often considered in patients with intolerable sedation, confusion, and/or inadequate pain control with oral opioid administration.5
Other interventional strategies are also used to reduce reliance on systemic opioids. In some instances, pain may be relieved with nerve block (e.g., pancreas/upper abdomen with celiac plexus block, lower abdomen with superior hypogastric plexus block, intercostal nerve, or peripheral nerve). Neuroablative procedures may also be used for well-localized pain syndromes (e.g., back pain from facet or sacroiliac joint arthropathy; visceral pain from abdominal or pelvic malignancy), such as percutaneous vertebroplasty/ kyphoplasty, neurostimulation procedures (i.e., for peripheral neuropathy), and radiofrequency ablation for bone lesions, may sometimes be helpful in managing pain.6
There is a significant medical need for new treatments in the management of severe cancer pain.
- Van den Beuken-van Everdingen MH, de Rijke JM, Kessels AG, Schouten HC, van Kleef M, Patijn J. Prevalence of pain in patients with cancer: a systematic review of the past 40 years. Ann Oncol. 2007 Sep;18(9):1437-49. Review.
- Goudas LC, Bloch R, Gialeli-Goudas M, et al. The epidemiology of cancer pain. Cancer Invest 2005;23:182–190.
- McNicol E, Horowicz-Mehler N, Fisk RA, et al. Management of opioid side effects in cancer-related and chronic noncancer pain: a systematic review. J Pain 2003;4:231–256.
- Kamdar MM, et al. Case records of the Massachusetts General Hospital. Case 17-2015. A 44-year-old woman with intractable pain due to metastatic lung cancer. N Engl J Med. 2015 May 28;372(22):2137-47. doi: 10.1056/NEJMcpc1404141.
- Greenberg HS, Taren J, Ensminger WD, Doan K. Benefit from and tolerance to continuous intrathecal infusion of morphine for intractable cancer pain. J Neurosurg 1982;57:360–364.
- Swarm R, et al. Adult cancer pain. J Natl Compr Canc Netw. 2010 Sep;8(9):1046-86.