Quantitation of FISH Signals in Archival Tumors

The term interphase cytogenetics was first used in 1986 by Cremer (1 ,2 ) to describe detection of chromosomal alterations using in situ techniques in interphase nuclei. This was a distinct advantage over conventional analyses as solid tumors could now be studied (2 ,3 ) and the possibility of applying the technique to specimens received in a diagnostic laboratory realised (4 ). The nonradioactive in situ method, fluorescence in situ hybridization (FISH), has been widely applied to study chromosomal rearrangements, malignancies, and chromosome mapping (4 ).