Genetic imbalances in benign bone tumors revealed by comparative genomic hybridization.

There have been no reports on choromosomal aberrations of benign bone tumors revealed by comparative genomic hybridization (CGH). CGH analysis of benign tumors may be useful in understanding the mechanism of tumorigenesis with comparisons to malignant tumors. There were 4 tumors (2 enchondromas, one chondromyxoid fibroma, and one osteoid osteoma) and 8 tumor-like conditions (4 aneurysmal bone cysts (ABCs), one eosinophilic granuloma, one fibrous dysplasia, one solitary bone cyst, and one Rosai-Dorfman disease) available for analysis. One of 2 enchondromas and one of 4 ABCs exhibited rapid growth. Six lesions showed chromosomal aberrations, while 6 others did not. The most frequent aberrations were the loss of a whole chromosome-19 in 6 cases, the loss of chromosome-arm 22q in 4 cases, and the loss of chromosome-arm 17p in 3 cases. Gains were seen in 13q21 in 2 cartilaginous tumors and at 12q15-q21 in eosinophilic granulomas. Therefore, in benign bone tumors or tumor-like lesions, chromosomal aberrations are not frequent; however, some clear tendencies of clustering of aberrations can be observed.