Clonal karyotypic aberrations in enchondromas

Enchondromas, benign cartilaginous tumors arising within the medullary cavity of bone, are frequently difficult to differentiate from their malignant counterpart. In this study, cytogenetic analysis was performed on seven cases of solitary enchondroma. Normal karyotypes were observed in five cases. Clonal abnormalities were detected in two cases. An isochromosome of the short arm of chromosome 6 characterized one case, and t(12;15)(q13;q26) in addition to random numerical and structural abnormalities such as telomeric association was observed in the other case. An i(6p) and structural rearrangements involving 12q13 previously have been described in chondrosarcoma. Our findings suggest that similar clonal karyotypic abnormalities exist in benign and malignant cartilaginous neoplasms.