An autopsy case report: Differences in radiological images correlate with histology in Erdheim-Chester disease.

p16 activation caused by oncogenic mutations may represent oncogene-induced senescence (OIS), a protective mechanism against oncogenic events. However, OIS can contribute to tumor development via tissue remodeling in some tumors. Erdheim-Chester disease (ECD), a rare non-Langerhans cell histiocytosis, is one such tumor. Its clinical and histological features vary, making it difficult to diagnose. Herein, we describe an autopsy of an ECD patient. The patient underwent radiological examinations, including 18 F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT), bone scintigraphy and CT. A biopsy from the lesion with the highest FDG accumulation confirmed the presence of foamy macrophages, a diagnostic clue for ECD. Based on this finding and the clinical features, ECD was diagnosed. However, the patient died from heart dysfunction. After the autopsy, each radiologically different site showed various histological findings regarding the morphology of macrophages, fibrosis, inflammation, and p16 expression. OIS-induced histological progression can cause certain changes observed in radiological images. In addition, in order to evaluate the increase in glucose metabolism, which can affect FDG accumulation, the expression of glucose transporter 1 and hexokinase II was also analyzed. Summarizing the radio-histological correlation can help further both the understanding and diagnosis of ECD.