Successful left hemihepatectomy and perioperative management of a patient with biliary cystadenocarcinoma, complicated with MELAS syndrome: Report of a case

Mitochondrial Myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like syndrome (MELAS) is a rare, fetal disease caused by a mutation in mitochondrial DNA that leads to impaired oxidative metabolism in skeletal muscle, the central nervous system, and liver function. This report presents the case of a 50-year-old woman with biliary cystadenocarcinoma complicated by MELAS who underwent a successful left hemihepatectomy. In this case, the diagnostic key for the malignant tumor was an ¹⁸F-fluorodeoxyglucose positron emission tomography study, which was useful even in a patient with MELAS, which causes abnormal glucose metabolism. The perioperative management of such patients includes special precautions to prevent lactic acidosis and deterioration of the reserved liver function after a hepatectomy, since the mitochondrial function in MELAS patients is abnormal. The patient in this report has remained free of liver dysfunctions and cancer recurrence for 2 years following the hepatectomy. This is the first report of a successful major hepatectomy for a patient with MELAS.