A challenging case of rapid progressive Kaposi sarcoma after renal transplantation: diagnostics by FDG PET/CT

De-novo malignancy is a serious posttransplant complication. While the incidence of Kaposi sarcoma (KS) is low, the time for its diagnosis is early after renal transplantation. Typically, it can be identified because of the classical skin lesion. We herein report an unusual case of rapid progressive KS without skin lesions in a 52-year-old patient leading to death within 8 months after kidney transplantation. This striking case illustrates the usefulness of [18F]2-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography for demonstrating the cause of unexplained deterioration of patient's condition. Early identification of KS is critical because early (modification of) therapy can substantially improve patient's prognosis.