[Modern imaging for detection and localization of distant metastases]

Imaging and staging of malignant tumors is an essential part of the practice of radiology and also an important focus of clinical radiological research. There are many different modalities for tumor imaging and the efficient use requires profound knowledge of their advantages and limitations. CT, ultrasound (US) and magnetic resonance (MRI) can provide images with high morphological details but often fail to detect minimal tumor agglomerations (micrometastases). New techniques such as positron emission tomography (PET) and the development of specific contrast agents can reveal changes at the physiological, cellular or molecular levels. In this review the advantages and limitations of the current imaging modalities are discussed and their application in the evaluation of the most common sites of metastasis described.