Clinical Challenges of Treating Breakthrough Cancer Pain

February 22, 2011

Effective treatment of breakthrough cancer pain requires a multidisciplinary approach, careful patient assessment, and an individualized treatment strategy.

Despite the availability of several effective treatment options, including well-tolerated fentanyl products, researchers report that breakthrough cancer pain continues to be underrecognized and undertreated.

Although the majority of patients undergoing treatment for cancer experience breakthrough cancer pain, and despite the fact that suboptimal breakthrough cancer pain treatment can have a severe negative impact on patients’ quality of life, diagnosis and treatment of breakthrough cancer pain remain poor due to a variety of factors.

In “Integrated Strategies for the Successful Management of Breakthrough Cancer Pain,” published in the journal Current Opinion in Supportive and Palliative Care, Andrew Dickman, a researcher at the Marie Curie Palliative Care Institute, in the UK, noted that the lack of a clear consensus definition of breakthrough cancer pain, concerns among patients and physicians regarding overmedication and addiction/dependence, “difficulties among healthcare professionals in differentiating [breakthrough cancer pain] from poorly controlled background pain,” and other barriers conspire to ensure that detection and treatment of breakthrough cancer pain remains less than optimal. Dickman also wrote that control of breakthrough cancer pain using traditional “rescue medications” is also problematic because “the pain relief afforded by morphine and other normal-release oral opioids, such as oxycodone and hydromorphone, does not appear to match the characteristics of the [breakthrough cancer pain] episode itself.”

The effects of untreated breakthrough cancer pain are pervasive, impacting nearly every aspect of affected patients’ lives. According to a survey conducted by the American Pain Foundation, “85% of patients who responded stated that breakthrough cancer pain negatively affects their quality of life, including their physical health, interpersonal relationships and ability to engage in certain activities.” A European study of oncology patients found that 63% of patients reported breakthrough cancer pain or inadequate pain relief “despite being prescribed analgesics.” More than half of these patients “reported inadequate pain relief all the time, every hour, several times daily, daily or several times per week, and yet, only a third (33%) of them were treated with additional analgesic medication.”

Effective treatment begins with proper recognition and assessment. Dickman noted that it is important for clinicians to “differentiate patients with uncontrolled background pain experiencing transient exacerbations of that pain from patients with controlled background pain experiencing episodes of breakthrough cancer pain.” When assessing patients for breakthrough cancer pain, “it is important to ascertain the temporal pattern of pain, any precipitating or exacerbating factors, any relieving factors, the response to opioid analgesics and the response to other therapeutic manoeuvres.” Assessment should include a detailed history and physical exam and the use of standard pain measures and questionnaires.

Barriers to treatment include physician-related causes such as inadequate knowledge of breakthrough cancer pain and underestimating and/or underappreciating the intensity of the patient’s pain, as well as concerns about “side-effects of opioids, prescription of ineffective doses of opioids, and failure to adequately address the undesirable effects of opioids.” Patients also contribute to suboptimal treatment by inadequately communicating to clinicians the extent and/or intensity of their pain, harboring heightened fears of the adverse effects of opioids, and failing to properly adhere to the prescribed medication regimen. Ideally, treatment for breakthrough cancer pain includes “a rescue dose of strong opioid with pharmacokinetic properties that closely match the temporal characteristics” of the patient’s pain. Treatment should provide demonstrable analgesic relief and combine rapid onset of action with a relatively short duration of action, be easy to administer, and have minimal adverse effects (the latter two characteristics especially contributing to improved adherence). Fentanyl preparations may be especially suitable for this role because they are “rapidly absorbed across mucosal membranes, with the promise of a rapid onset that more closely matches the profile of the ideal rescue treatment.” Dickman notes that formulations of fentanyl that use “advanced delivery systems provide efficacious pain therapy with minimal side-effects and are often preferred by patients compared with traditional oral opioids” used for the treatment of breakthrough cancer pain.

In addition to taking appropriate measures to deter and prevent misuse and abuse of fentanyl products, physicians treating patients for breakthrough cancer pain should combine a “multidisciplinary approach, careful patient assessment, and a treatment strategy tailored for the individual patient that considers the cause and type of [breakthrough cancer pain], as well as patient preferences.”

Clinical Pearls

  • It is important to distinguish breakthrough cancer pain from end-of-dose pain, “which can occur before a scheduled dose of background analgesic and generally arises due to an inadequate dose of analgesic or extended dosing interval.”
  • Effective pain management requires a comprehensive, individualized, multidisciplinary approach that may incorporate a combination of pharmacological and nonpharmacological treatment modalities.
  • Oral formulations of morphine and opioid rescue medications may not provide optimal responsiveness for breakthrough cancer pain “because the analgesia provided occurs after the [breakthrough cancer pain] has spontaneously subsided.”
  • It is important that patients, caregivers and clinicians receive appropriate education to dispel the fears and myths surrounding opioids.

Discussion Questions

Do you use fentanyl products or oral opioids to treat breakthrough cancer pain in your patients?

Do you have a preferred product for treating patients for breakthrough cancer pain?

Do you agree with the study author’s statements that inadequate knowledge of breakthrough cancer pain on the part of many clinicians contributes to the pervasive undertreatment of this condition?