Pain management in patients undergoing treatment for head and neck cancer with opiate use disorder on medication-assisted treatment.

Abstract

120 Background: Buprenorphine, a partial agonist at the mu opiate receptor, is an effective pain medication and use has increased for patients with cancer pain, especially those with concurrent opiate use disorder (OUD). Substance use disorder is common in head and neck cancer patients since alcohol and tobacco are predisposing factors. Definitive chemoradiation (chemoRT) for head and neck cancer is a difficult treatment with a high burden of symptoms, including mucositis pain, dysphagia and odynophagia. Patients undergoing concurrent chemoRT routinely require systemic opiates to manage pain and tolerate treatment. This is a review of our institution’s experience using buprenorphine and methadone for pain management in patients with OUD during chemoRT for head and neck cancer. Methods: We reviewed all cases seen in the Lifespan Cancer Institute head and neck cancer multidisciplinary clinic between July 2018 and June 2019. Approximately 40% of patients had a history of opiate use disorder and one-fifth of those were on medication-assisted treatment with buprenorphine or methadone. The charts of patients with OUD were reviewed with respect to history of buprenorphine or methadone use, pain scores during chemoRT, effectiveness of pain medications during chemoRT, and change of pain medication during treatment. Results: 5 patients on buprenorphine and 4 patients on methadone underwent treatment with chemoRT for head and neck cancer. Despite effectiveness for pain with other cancer patients, we did not find that buprenorphine was an effective opiate for patients undergoing chemoRT for head and neck cancer. All patients on buprenorphine had to be rotated off to another opiate (generally methadone) to achieve adequate pain relief. Median time to pain medication change was 3 weeks (range: prior to starting to week 5/7). The patients on methadone generally were able to tolerate treatment with minor adjustments to their methadone. Conclusions: The ceiling effect of buprenorphine that makes it effective for OUD is a barrier to managing the severe pain from chemoRT for head and neck cancer, while methadone is effective for both pain control and maintenance of sobriety during a taxing treatment.