Therefore, the purpose of this study is (1) to evaluate the ability of experienced readers of MR imaging to distinguish between lipoma and ALT/WDLs in the era of MDM2 FISH, (2) to evaluate the agreement of MRI interpretations amongst experienced readers, (3) to evaluate the utility of the diagnostic formula proposed by Wang et al., and to determine whether or not it is able to outperform the interpretation of fellowship-trained readers, and (4) to determine which MRI characteristics, if any, are most predictive of the diagnosis of ALT/WDLs. This evidence concerns the gene GPT and lipoma.