Methadone analgesia for children with advanced cancer

Background. Methadone is frequently used in the treatment of adults with advanced cancer. A criticism of relevant research is the use of single or fixed doses, which does not reflect use in clinical practice. Literature about use of methadone in the treatment of pediatric patients is limited to case reports. The objective of this study is to describe methadone use as primary opioid analgesic for advanced pediatric cancer over a 6.5-year period. Procedure. All 17 patients who received methadone as their primary opioid analgesic through the Northern Alberta Children's Cancer Program from January 2000 to June 2007 were included. Children who received combination opioid therapy were excluded. Results. Rotation to methadone was usually by a complete switch from primary opioid. Conversion ratios of morphine equivalent daily dose (MEDD)/methadone daily dose (TMDD) ranged widely from 1:2 in one patient with sudden pain crisis just prior to death, to 60:1 in a patient who had been treated with opioids for months. Methadone was used for a total of 925 patient-days. There were no significant adverse events in any patient, and all but one patient remained on methadone until the time of their death. Clinically, the effectiveness of analgesia clearly improved at time of conversion in 16 patients. Conclusion. With close monitoring, methadone therapy can be done safely in pediatric oncology patient populations in both inpatient and outpatient settings. Our experience suggests improvement in analgesia with the use of methadone, with 16 patients remaining on methadone until they died.