FLUORESCENCE IN-SITU HYBRIDIZATION (FISH) FOR RETROSPECTIVE DETECTIONOF TRISOMY-3 AND TRISOMY-7 IN MULTIPLE-MYELOMA

The malignant plasma cells of multiple myeloma (MM) have a low prolife rative activity and therefore cytogenetic studies of the disease have been severely limited. We evaluated the role of fluorescence in situ h ybridization (FISH) in the detection of numerical chromosomal abnormal ities in early stages of myeloma and the applicability of the method t o stored archival slides. Old air-dried bone marrow smears From 15 mye loma patients obtained at presentation were probed with a satellite DN A sequences to chromosomes 3 and 7. Numerical chromosome aberrations w ere found in eight (53%) of the patients, including six (of 12) with t risomy 7, and two (of eight) with trisomy 3. This study demonstrates t hat FISH is a sensitive method for the detection of numerical aberrati ons in myeloma and for the study of old slides for retrospective analy sis.