Imaging strategies for oncologic diagnosis and staging

Radiology plays a more dominant diagnostic role in most other disease settings than in oncology. The primary applications of imaging procedures in the patient with cancer are in tumor definition, staging and follow-up. There are notable exceptions to this statement (mammography and hollow organ GI examination). Nonetheless, experience has demonstrated that random screening, utilizing radiographic studies, cannot be justified in view of both yield and cost. In taking stock of the advances that the field of oncology has enjoyed in the past few decades, most have involved improvements in treatment, with few in the area of cancer detection. Certainly diagnostic tools have become more sophisticated, accurate, and specific, but have these improved imaging techniques identified a population of smaller tumors that resulted in improved overall survival? In large measure, the answer is clearly no. The reasons are many, complex, and controversial, but they must be reviewed to place the problem in its proper perspective. Several factors are considered, including such limitations as the imaging process, the disease, and treatment considerations that are relevant to the discussion