Osteoid osteomas with chromosome alterations involving 22q

Cytogenetic analysis was performed in two osteoid osteomas. In both, the mo dal chromosome number was 46. One of the cases presented a del(22)(q13.1) a s the sole clonal chromosome alteration. The other had clonal monosomies of chromosomes 3, 6, 9, 17, 19, and 21, as well as a +del(22)(q13.1) was dete cted as a non-clonal chromosome alteration. There is only one osteoid osteo ma reported so far showing clonal karyotypic alterations. The cytogenetic b ehavior of osteoid osteomas described here was different from that of the o steoid osteoma of the literature. Numerical alterations of chromosomes 3, 6 , 9, 17, 19, 21 and 22 have been described in several neoplasias including bone tumors. The breakpoint of chromosome 22 involves a region where import ant genes for the regulation of the cell cycle have been mapped. (C) 2001 E lsevier Science Inc. All rights reserved.