Cytogenetical observations in human benign uterine leiomyomas.

Detailed observations by banding technique in 21 cultured human benign uterine leiomyomas are reported. More than half of the tumors (51%) had a primary or secondary abnormal stemline. The abnormal stemlines were usually characterized only by structural changes, in particular reciprocal translocations. These translocations, as well as instances of inversions, predominantly affected the chromosome types Nos. 1,2 and 12 and preferentially the regions 1p36, 2p24 and 12q14-15. Available data concerning cytogenetical deviations in benign human tumor types indicate that, in contrast to most malignant neoplasms, they are characterized by comparatively few and simple, either numerical or, more frequently, structural changes. The biological implications of these deviations are rapidly emerging as one of the most urgent areas for future studies with molecular techniques.