CYTOGENETIC FINDINGS IN 4 MALIGNANT MIXED MESODERMAL TUMORS OF THE OVARY

Short-term cultures of four malignant mixed mesodermal tumors of the o vary were cytogenetically analyzed. The primary tumor was examined in three cases, whereas in one case the sample was obtained fr om a resid ual tumor mass after chemotherapy. The tumor sampled after cytostatic treatment had a relatively simple karyotype with numerical changes tha t included pentasomy 12 and an i(1)(q10) as the only structural abnorm ality. Karyotypic analysis of the three primary tumors revealed extens ive structural as well as numerical aberrations, i.e., a picture simil ar to that seen in the few malignant mixed mesodermal tumors with kary otypic anomalies described previously. Rearrangements of chromosome 1, leading to loss of distal 1p, and homogeneously staining regions have so far been the most frequent cytogenetic changes in this tumor type. Malignant mixed mesodermal tumors of the ovary thus seem to be karyot ypically identical to the more numerous mixed mesodermal tumors of ute rine origin, and they do not differ substantially in this respect from pure ovarian carcinomas.