Molecular Cytogenetic Analysis of a Gliosarcoma with Osseous Metaplasia

Gliosarcoma, a rare glioblastoma variant, is composed of a glial and a mesenchymal component. Though the mesenchymal portion most commonly resembles a fibrosarcoma, other differentiation patterns have been observed. We present the first genomic characterisation (karyotyping followed by FISH and array-CGH analysis) of a gliosarcoma with osseous metaplasia. In addition to chromosomal changes often found in gliomas (+7,-10,-13, and -22), the tumour cells also harboured a hitherto unknown 3q21;21q21~22-translocation. As translocations are very rare in high-grade astrocytic tumours and have not formerly been seen in gliosarcomas, it is possible that the t(3;21) may be characteristic of gliosarcoma with osseous metaplasia. Tumour sample analysed with control DNA (supplied by Agilent)