Formalin-fixed and paraffin-embedded blocks from ovarian serous carcinoma cases were available from tumor-sections corresponding to the frozen blocks from which DNA-aliquots were obtained for SNP-array hybridization. Multiple curls containing at least 70% tumor cell nuclei were cut to an aggregate thickness of 150 microns. Sections were disaggregated and labeled with propidium iodide (DNA stain). FACS was performed to determine ploidy.
