RING CHROMOSOME-4 AS THE SOLE CYTOGENETIC ANOMALY IN A CHONDROBLASTOMA - A CASE-REPORT AND REVIEW OF THE LITERATURE

Chromosome analysis of a chondroblastoma of the right distal femur in a 31-year-old male patient revealed a ring chromosome 4 in approximate ly one-third of the analyzed cells. The remaining cells had a normal k aryotype. These findings were subsequently confirmed by fluorescence i n situ hybridization (FISH) with a chromosome-4-specific library. FISH with cosmids pC847.351 (4p16.3) and cT171 (4q35) revealed that fewer than 300 kilobase pairs (kbp) are deleted. To our knowl edge, ring chr omosome 4 has never been reported in this type of neoplasm. There are, however, several reports of chondroblastoma with other chromosome abn ormalities, but the relation of these anomalies to this tumor specific ally is unclear. In this report, we also provide a review of the liter ature concerning cytogenetic studies in chondroblastoma. The possible significance of ring chromosome 4 in this type of tumor is discussed. (C) Elsevier Science Inc., 1998