MODIFIED INTERPHASE CYTOGENETICS TECHNIQUE AS AN ADJUNCT IN THE ANALYSIS OF ATYPICAL CELLS IN BODY-FLUIDS

Our objective was to determine the value of a modified interphase cyto genetics technique (MICT) by fluorescence in situ hybridization (FISH) in the study of atypical cells in body fluids in previously stained s lides, allowing a direct morphologic-cytogenetic correlation. Thirty-f ive cases (29 bladder washes, four pleural fluids, two ascitic fluids) initially diagnosed as ''atypical'' with subsequent histologic confir mation were included. Histologically, there were 25 malignant, four dy splastic, and six benign lesions. Previously Papanicolaou or Diff-Quic k-stained slides were marked to determine the location of the cells of interest prior to FISH analysis. A pretreatment modification using pe psin digestion was utilized. Chromosome-specific probe 8 (Vysis) was u sed to detect numerical chromosomal abnormalities (NCA) involving chro mosome 8. Various NCA (aneuploid) were detected in the atypical cells of histologically proven malignant cases but not in the benign cases. Using histology as a ''gold standard,'' FISH has a sensitivity of 83% and a specificity of 100%. In conclusion this study shows that a MICT by FISH on previously stained slides can serve as an adjunct in the st udy of atypical cells in body fluids. This technique allows a direct m orphologic-cytogenetic correlation which in the future may aid in the better understanding of carcinogenesis. (C) 1997 Wiley-Liss, Inc.