Tumors in von Hippel–Lindau Syndrome: From Head to Toe—Comprehensive State-of-the-Art Review

Von Hippel–Lindau syndrome (VHL) is an autosomal-dominant hereditary tumor disease that arises owing to germline mutations in the VHL gene, located on the short arm of chromosome 3. Patients with VHL may develop multiple benign and malignant tumors involving various organ systems, including retinal hemangioblastomas (HBs), central nervous system (CNS) HBs, endolymphatic sac tumors, pancreatic neuroendocrine tumors, pancreatic cystadenomas, pancreatic cysts, clear cell renal cell carcinomas, renal cysts, pheochromocytomas, paragangliomas, and epididymal and broad ligament cystadenomas. The VHL/hypoxia-inducible factor pathway is believed to play a key role in the pathogenesis of VHL-related tumors. The diagnosis of VHL can be made clinically when the characteristic clinical history and findings have manifested, such as the presence of two or more CNS HBs. Genetic testing for heterozygous germline VHL mutation may also be used to confirm the diagnosis of VHL. Imaging plays an important role in the diagnosis and surveillance of patients with VHL. Familiarity with the clinical and imaging manifestations of the various VHL-related tumors is important for early detection and guiding appropriate management. The purpose of this article is to discuss the molecular cytogenetics and clinical manifestations of VHL, review the characteristic multimodality imaging features of the various VHL-related tumors affecting multiple organ systems, and discuss the latest advances in management of VHL, including current recommendations for surveillance and screening

Sarcoidosis from Head to Toe: What the Radiologist Needs to Know

Sarcoidosis is a multisystem granulomatous disorder characterized by development of noncaseating granulomas in various organs. Although the etiology of this condition is unclear, environmental and genetic factors may be substantial in its pathogenesis. Clinical features are often nonspecific, and imaging is essential to diagnosis. Abnormalities may be seen on chest radiographs in more than 90% of patients with thoracic sarcoidosis. Symmetric hilar and mediastinal adenopathy and pulmonary micronodules in a perilymphatic distribution are characteristic features of sarcoidosis. Irreversible pulmonary fibrosis may be seen in 25% of patients with the disease. Although sarcoidosis commonly involves the lungs, it can affect virtually any organ in the body. Computed tomography (CT), magnetic resonance imaging, and positron emission tomography/CT are useful in the diagnosis of extrapulmonary sarcoidosis, but imaging features may overlap with those of other conditions. Familiarity with the spectrum of multimodality imaging findings of sarcoidosis can help to suggest the diagnosis and guide appropriate management