Diffuse Liver Uptake of Technetium-99m-MDP Bone Scan Due to Hepatotoxicity Secondary to Methotrexate Therapy

Bone scintigraphy is a common and sensitive modality for detecting either primary or secondary bone malignancy. Sometimes additional information could be found besides skeletal abnormalities. An eleven-year-old female who was diagnosed osteogenic sarcoma underwent technetium-99m-methylene diphosphonate ((superscript 99m)Tc-MDP) whole body bone scan to survey the distant metastasis status. Diffuse liver uptake of (superscript 99m)Tc-MDP was noted incidentally. According to the clinical history. high dose methotrexate was given one day prior to bone scan performed and the laboratory data showed marked elevation of serum alanine aminotransferase (GPT). Therefore, methotrexate-induced hepatotoxicity is considered to be the cause of the diffuse liver uptake of (superscript 99m)Tc-MDP. The mechanism of extraskeletal uptake of bone-seeking radiopharmaceuticals in damaged, inflamed, neoplastic or necrotic tissues may be due to dystrophic calcification and is associated with cell injury and calcium deposition. Owing to the acute hepatotoxicity corresponding to laboratory and clinical findings, the protocol was adjusted and the neoadjuvant chemotherapy was completed smoothly. This case demonstrates an example of unusual diffuse hepatic uptake of (superscript 99m)Tc-MDP resulted from the hepatotoxicity and for patients that are receiving chemotherapy, the regimen may need adjustment if the hepatotoxicity is presented.