NONRANDOM SECONDARY CHROMOSOME-ABERRATIONS IN SYNOVIAL SARCOMAS WITH T(X-18)

Thirty samples from 19 patients with synovial sarcoma were analyzed cy togenetically after short-term culturing. Thirteen samples were from p rimary tumors, 11 from local recurrences, and six from distant metasta ses. All samples showed the characteristic aberration t(X;18)(p11;q11) or variants thereof; 23 samples had additional numerical and/or struc tural changes. Including the present cases, chromosome aberrations hav e been reported in 74 synovial sarcomas, 50 of which have had secondar y aberrations in addition to t(X;18). No secondary structural aberrati on was recurrent. The most common numerical changes were +7, +8, +12 ( 10 cases each), -3, +9, +21 (7 cases each), +2, -14, -17 (6 cases each ), +4, -11, +15, and -22 (5 cases each). Unbalanced stuctural aberrati ons led to loss of 3p and 17p in six cases, each with loss of bands 3p 21 and 17p13, respectively, in common. Most monosomies and trisomies s eemed to occur at similar frequencies in primary, recurrent, and metas tatic tumors. The only exceptions were +2, which was never seen in a p rimary tumor, and +8, which was never found in any metastatic lesion.