Fluorescence in situ Hybridization in Cytopathology

Abstract

The application of ancillary studies to small biopsies and cytopathology specimens has been increasing for definitive diagnoses and theranostic information. Fluorescence in situ hybridization (FISH) is one of the ancillary techniques being applied to these small specimens, and has been utilized with great success for years, particularly in the diagnosis of lymphomas and other hematolymphoid lesions. However, there is now an increasing array of probes available for different tumors, particularly in salivary gland pathology, soft tissue pathology, and solid tumor pathology, which has increased the use of FISH in a variety of different settings. This chapter will review the realm of FISH tests being applied to cytological specimens, and discuss the clinical significance of these tests and their use in different tissue types being biopsied.