CLONAL CHROMOSOME-ABERRATIONS IN 3 SACRAL CHORDOMAS

Cytogenetic analysis was successful in seven of eight sacral chordomas . Clonal chromosome aberrations were detected in three. One had a t(1; 6)(q44;q11) as the sole aberration, one displayed three near-diploid c lones that shared de1(2)(p22), de1(9)(p13), -10, structural rearrangem ents of 12q13, and add (19)(p13), and the third chordoma had two aberr ant cell populations - one hypodiploid with several numerical and stru ctural changes, the other hypertriploid-hypotetraploid with all marker chromosomes in duplicate. including the present cases, seven cytogene tically aberrant chordomas have been reported. Five have had hypodiplo id clones and the most frequent changes have been - 3, -4, -10, and -1 3. No recurrent structural rearrangement has been identified; the only chromosome bands involved more than once are 1q21, 3q11, 5p15, 20q13, and 21q22.