Challenges and Breakthroughs in Cancer Pain Management
Cancer pain management has greatly improved with advances in oral and intravenous medication. However, several challenges still exist in administration.
Judith A. Paice, PhD, RN, FAAN
Cancer pain management has greatly improved with advances in oral and intravenous medication. However, several challenges still exist in administration. Judith A. Paice, PhD, RN, FAAN, a research professor in medicine-hematology/oncology at the Robert H. Lurie Comprehensive Cancer Center of Northwestern University in Chicago, Illinois, discussed the management of cancer pain at the 2012 NCCN Annual Meeting.
According to NCCN guidelines, pain should be assessed for location, duration, intensity, quality (nociceptive, neuropathic, or visceral), timing, and aggravating or alleviating factors. Cancer patients with pain should also be assessed for other symptoms, current therapies, prior treatment response, function changes, family history of substance abuse, and risk factors for aberrant use or diversion.
“The goals of treatment include prevention, relief of pain, improved function, [and] safety,” Paice said.
Specifically, she said analgesia versus safety is a major challenge with pain management. For example, while acetaminophen is commonly used for cancer pain, many patients are unaware of how many treatments they are taking that include the drug, increasing their risk of an overdose.
Currently available treatment options for pain management include non-opioids (acetaminophen or NSAIDs), opioids, adjuvants, and anticancer therapies.
Opioids are fundamental to good cancer pain management and are available in several forms, including tablets, sublingual tablets, buccal soluable film, and nasal spray. Typically, these agents require prior authorization or partial fills and are associated with a variety of side effects ranging from respiratory depression and sedation to nausea and vomiting.
Adjuvant options include corticosteroids, antiepilepsy drugs, antidepressants, local anesthetics, NMDA receptor antagonists, and cannabinoids. Corticosteroids can be administered orally, intravenously, or epidurally, and have been shown to be effective in reducing pain. However, corticosteroids may produce psychosis and longterm use may lead to proximal muscle wasting.
Of the anti-epilepsy drugs, gabapentin is generally the most well-tolerated and is often used for breakthrough pain or neuropathic pain. However, the drug is administered three times per day and may be associated with dizziness and sedation. Pregabalin is another anti-epilepsy drug that has been associated with improved bioavailablity at high doses.
Antidepressants, including tricyclics (nortriptyline and desipramine) and serotonin—norepinephrine reuptake inhibitors (venlafaxine and duloxetine), have been effective in providing good pain control with limited adverse events. Local anesthetics, such as lidocaine patches or creams, have been effective in treating localized pain.
Due to the challenges associated with medical marijuana, manufacturers are testing synthetic compounds that target CB1 and CB2 receptors, as these agents provide pain control without the euphoric feeling associated with medical marijuana.
Overall, Paice said that there are several effective agents available for cancer pain, but practitioners need to be aware of the risk of adverse events and drug-drug interactions associated with these treatments.