Parachordoma: a rare sarcoma with clonal chromosomal changes.

This is the first report on clonal chromosomal aberrations in a metastatic parachordoma lesion. All neoplastic cells had the karyotype 33-47,X,der(X)t(X;3) (p11;p11),der(3)t(3;6)(p11;q13), del(6)(q13), -9, -13,r(13), +mar. The presence of t(X;3) with a breakpoint at band Xp11 as in synovial sarcoma may suggest a common histological origin of the two tumor types.