DETECTION OF NUMERICAL CHROMOSOMAL CHANGES IN 20 MALIGNANT FIBROUS HISTIOCYTOMAS BY FISH

We investigated 20 malignant fibrous histiocytomas (MFHs) with the hel p of specific centromeric probes for chromosomes 1, 3, 4, 6, 8, 9, 12, 16, 17 and 18. The results show a broad variation in the number of si gnals per nucleus. However, tumors can be assigned into four groups: i ) with mostly disomic clones, ii) with a high percentage of polysomic clones, iii) with a considerable amount of monosomic and nullisomic cl ones and iv) with a tendency in both directions. A gain of-spots per n ucleus takes place in 75-100% of the investigated tumors - the highest incidence occurring with respect to chromosome 3. A loss of spots per nucleus occurred in 20-60% of the tumors - predominantly with respect to chromosome 1.