Fluorescence in situ hybridization: a new tool for the pathologist.

DNA in situ hybridization methods permit investigations of genetic alterations within the context of cell morphology and tissue architecture and are of particular importance in tumor pathology. Detection of specific chromosome aberrations may be a critical adjunct to diagnosis or prognosis when morphology is ambiguous. This approach will lead to better understanding of heterogeneity in tumors and to better definition of premalignant lesions.