Osteoid osteoma and osteoblastoma with clonal chromosome changes

We cytogenetically investigated six osteoid osteomas, one osteoblastoma and one aggressive osteoblastoma, and observed clonal structural changes in one osteoid osteoma and in the aggressive osteoblastoma. Clonal chromosome changes had not been reported previously in osteoid osteoma, whereas the only reported chromosome change in osteoblastoma was different from the one presented here.