A Case of Esophagogastric Junction Cancer Treated with Pain Control by Administering Methadone Tablets Through a Gastrostomy.

Introduction: Methadone is used to treat intractable cancer pain when other opioid analgesics are ineffective. Methadone tablets may be difficult to administer in cases of gastrointestinal passage obstruction. However, changing the route of methadone tablet administration is possible. Case Description: The patient, diagnosed with esophagogastric junction cancer with multiple metastases, continued to receive methadone tablets even after not being longer able to take oral medication. Method: Methadone tablets were administered using a simple suspension method via gastrostomy. We measured the respiratory rate during sleep daily. We also measured weekly QTc values using a 12-lead electrocardiogram and methadone blood concentration periodically. No side effects were observed. Conclusion: Using a simple suspension method to administer methadone is a safe pain management method when accompanied by careful monitoring. To date, no study has examined the tube administration safety of methadone tablets. Thus, this case report is of important clinical significance.