Changes in Cancer Pain
Allyson Bryant, MD
Wake Forest Baptist Medical Center
Comprehensive Cancer Center
at Wake Forest Baptist Health
A report by the American Cancer Society in 2012 estimated that there are 13.7 million cancer survivors in the United States, with projected growth to 18 million by 2022.1
The surgery, radiation therapy, and chemotherapy treatments that lead to survivorship sometimes have painful sequela.
Opioids have long been the mainstay of treatment for severe, acute, and terminal cancer-related pain. Previously, the limited time of opioid administration avoided problems of chronic opioid use, including tolerance, substance abuse, opioid-induced hyperalgesia, hormone changes, and osteoporosis. The rise in survivorship has increased chronic pain in the cancer pain population, the treatment of which has many fundamental differences when compared to acute and terminal cancer pain.2Past Approach to Cancer Pain Treatment
The WHO “analgesic ladder” teaches basic principles including the utilization of adjuvants and nonopioid therapy as first-line treatments with the addition of opioids for moderate to severe pain. A guiding principle of opioid therapy with this approach is to treat increasing pain with increasing opioid dosing until limited by side effects. When utilized for acute management during painful cancer treatments or for palliative care, these management principles have aided treatment and been effective. The tradition of justifiable opioid escalation when paired with increased rates and lengths of survival expose this surviving population to the pitfalls of longterm opioid treatment.2,3New Approach to Cancer Pain Treatment
The common causes of chronic pain in patients with cancer include peripheral neuropathies from radiation and chemotherapy, radiation fibrosis, postsurgical incisional pain, arthropathies and musculoskeletal pain, and visceral abdominal pain.2
Opioid-induced hyperalgesia and tolerance associated with chronic pain may be more difficult to manage and treat in patients who have been rapidly titrated to high doses as indicated by the “analgesic ladder.”
One solution that would aid in the treatment and possibly decrease the development of chronic pain in the surviving cancer population would be identification of at-risk populations based on diagnosis, disease stage, and planned therapies at the time of diagnosis. Once identified, beginning targeted early interventions aimed at reducing opioid dosing with alternate therapies including nerve blocks, behavioral and cognitive therapy, and nonopioid pain medications prior to the initiation of opioids or during the initial acute pain episode, may reduce the number of patients with chronic pain and decrease the number who are receiving high-dose opioids when they begin chronic pain treatment. Implementation would require a paradigm shift to preventing chronic pain that is in concordance with the preventive medicine approach being adopted in many other specialties of medicine.
Simon, Stacy. New report tracks growing population of cancer survivors in the US. American Cancer Society. http://bit. ly/1EAKMW0. Published June 14, 2012. Accessed May 1, 2015.
Ballantyne, JC. Chronic pain following treatment for cancer: the role of opioids. Oncologist. 2003;8(6):567-575.
Breivik, H. Opioids in cancer and chronic non-cancer pain therapy—indications and controversies. Acta Anaesthesiol Scand. 2001;45(9):1059-1066.