Scintigraphic imaging of breast tumors.

Technetium-99m-sestamibi scintigraphy has recently emerged as a new procedure for the imaging of malignant breast tumors. A large clinical experience has now been collected and this article reviews the main published results. The major drawback of the procedure appears to be its low sensitivity in detecting lesions smaller than 1 cm. The biological background underlying the tracer accumulation is also described. The stimulating potent applications of this functional imaging technique to non-invasively explore the development, and possibly the reversal, of a multidrug resistance under chemotherapy are discussed. The data related to the use of the positron emitter fluor-18-labeled fluorodeoxyglucose (FDG), a very promising agent for imaging breast as well as other solid tumors, are also reviewed. This situation of specific agents, still under development and such as labeled receptor ligands, is examined.