ASCO GUIDELINES FOR CHRONIC PAIN

As many as 40% of the 14 million-plus cancer survivors in the United States today report experiencing significant chronic pain and impaired quality of life.

Now for the first time, there are guidelines for physicians on how to manage chronic pain in these individuals. Produced by the American Society of Clinical Oncology (ASCO), the new guidelines were published online July 25 in the Journal of Clinical Oncology.

The document discusses analgesic interventions, nonpharmacologic therapies, and the best evidence-based treatment options. The recommendations include screening for pain at each patient meeting and understanding how to minimize abuse, addiction, and adverse consequences when prescribing opioids for patients who don't respond to conservative pain management.

"As the population of cancer survivors expands, all clinicians, including oncologists, advanced practice providers, and primary care physicians who interact with these individuals will require the knowledge and skills to implement best practices in the management of chronic pain," says the ASCO-convened expert panel led by Judith A. Paice, PhD, RN, research professor in medicine-hematology/oncology at Northwestern University Feinberg School of Medicine in Chicago, Illinois.

"When analgesic drugs are used, the imperative to prescribe safely must expand beyond immediate adverse effects, such as the resulting respiratory depression or constipation associated with opioids, to incorporate awareness and mitigation of the long-term consequences of these and other analgesic agents," the authors note.

First Guideline, an Important Starting Point 

"This is the first guideline in this population of cancer survivors with chronic pain, and an important starting point for clinicians who are caring for them," Dr Paice said in an interview.

The guidelines "very clearly" describe the complex pain syndromes of cancer survivors, she said. Typically, these pain syndromes occur after treatment and include chemotherapy-induced peripheral neuropathy as well as neuralgias experienced by women treated for breast cancer who must receive aromatase inhibitors for 5 to 10 years.

Less common pain syndromes are also described. "It's comprehensive because the problem of chronic cancer pain is enormous and there is a risk of undertreatment and overtreatment," Dr Paice said.

The guidelines, which are relevant for all clinicians, also describe how to screen for risk for opioid misuse and how to develop strategies to avoid this. They discuss how to get a patient off an opioid that is no longer needed or is causing harm. "This is rarely included in medical training," Dr Paice told Medscape Medical News.

Once pain management strategies based on risk are in place for each individual patient, for instance, random toxicology is recommended, along with the use of prescription drug monitoring programs — available in 49 states — to check whether a patient is "doctor shopping" for multiple prescriptions.

"It's not the pain meds themselves that put people at risk of addiction," Dr Paice explains, pointing to factors that predict opioid misuse, such as alcohol abuse, cigarette use, and a strong family history of addiction. A history of physical and sexual abuse in childhood or adolescence is associated with the greatest risk for opioid misuse. 

Pharmacologic therapies aren't the only treatment for pain, she points out. Physical medicine and rehabilitation that promote exercise is one of the most important treatment options for people in pain.

Cognitive-behavioral therapy and other mental health counseling strategies are also "really crucial pieces of comprehensive treatment," Dr Paice said, adding that "the challenge has been reimbursement."

While more research into both pharmacologic and nonpharmacologic therapies is needed, concerns about access to pain medication were addressed in the ASCO policy statement on opioid therapy released last May, she said.

Systematic Review of Medical Literature 

For the guidelines, the panel conducted a systematic review of the medical literature from 1996 to 2015. They looked at outcomes in any adult diagnosed with cancer who had pain lasting 3 months or more, and they searched 35 systematic reviews, 9 randomized controlled trials, and 19 comparative studies as well as clinical experience.

Outcomes included symptom relief, pain intensity, quality of life, functional outcomes, adverse events, misuse or diversion, and risk assessment or mitigation.

Because most studies were not directly comparable and high-quality evidence often was lacking, many recommendations are based on expert consensus, they say.

Key Recommendations

Key recommendations for clinicians in the new guidelines include the following:

• Screen for pain each time you see the patient by using a quantitative tool, such as a two- question verbal screen. This can be as simple as asking, "Have you had frequent or persistent pain since the last time you were seen?" If the answer is yes, then ask, "How severe has this pain been, on average, during the past week?" A verbal rating scale or a numeric scale can then be used to identify patients who should undergo an initial comprehensive pain assessment.
• Create the initial comprehensive pain assessment using an in-depth interview to determine cause and develop a treatment plan. The interview should solicit information on cancer treatment, comorbid conditions, and psychosocial and psychiatric history —including substance use — and prior treatments for pain.
• Be aware that many patients with a history of cancer may also report chronic pain unrelated to the cancer, such as arthritis, degenerative disk disease, or diabetic neuropathy.
• Evaluate, treat, and monitor recurrent disease, second malignancy, or late-onset treatment effects in any patient who reports new-onset pain.
• Determine the need to get other health professionals involved. Refer accordingly.
• In the absence of serious drug–drug interactions, nonsteroidal anti-inflammatory drugs; acetaminophen (paracetamol); adjuvant analgesics, including selected antidepressants, such as duloxetine (Cymbalta); and selected anticonvulsants, such as gabapentin( Gralise, Horizant, Neurontin, Gabarone) or pregabalin (Lyrica) and anticonvulsants for neuropathic pain conditions or chronic widespread pain may be prescribed.
• The efficacy and long-term effectiveness of other systemic nonopioids, including other antidepressants and anticonvulsant drugs, as well as complementary or alternative medicines, have not been established.
• Topical analgesics, such as nonsteroidal anti-inflammatory drugs, local anesthetics, or compounded creams/gels containing baclofen (Lioresal, Lioresal Intrathecal, Gablofen), amitriptyline (Vanatrip, Elavil, Endep), and ketamine (Ketalar) may be prescribed.
• Corticosteroids are not recommended for long-term relief of chronic pain in cancer survivors.
• Clinicians may follow specific state regulations that allow access to medical cannabis or cannabinoids.
• A trial of opioids may be prescribed in selected cancer survivors after assessment of risks for adverse effects and the potential risks and benefits with long-term use.
• Patients and family member/caregivers should be educated about use of opioids, and the patient's literacy level and/or cultural background should be considered.
• A universal precautions approach to minimize abuse, including random toxicology screening, is recommended.
• Exercise caution in coprescribing other centrally acting drugs, particularly benzodiazepines.
• If opioids are no longer warranted, taper the dose to avoid abstinence syndrome and consider cotherapies to reduce adverse effects.

Adding nonpharmacologic therapies to the comprehensive pain management plan is recommended, including the following:

• Physical medicine and rehabilitation (physical therapy, occupational therapy,
• Integrative therapies (massage, acupuncture, music);
• Psychological therapies (cognitive-behavioral therapy, distraction, mindfulness); and
• Neurostimulatory therapies (transcutaneous electrical nerve stimulation, spinal cord stimulation, peripheral nerve stimulation, transcranial stimulation).

Additional information is available at www.asco.org/chronic-pain-guideline.

Dr Paice and several coauthors have disclosed no relevant financial relationships. Coauthor Marc Citron, MD, disclosed relationships with Novartis, Genentech, Pfizer, Bayer Schering Pharma, Merck, Pfizer, and Puma Biotechnology, and coauthor Louis S. Constine, MD, disclosed relationships with UpToDate, Springer, and Lippincott.