"Benign" metastasizing giant cell tumor: evaluation of nuclear DNA patterns by flow cytometry.

Nuclear deoxyribonucleic acid (DNA) ploidy was determined by flow cytometry for nine histologically benign giant cell tumors that developed systemic metastases and for eight tumors that did not metastasize. Specimens from the primary tumor, local recurrences, and pulmonary metastases were evaluated. No feature of the DNA ploidy pattern was identified to distinguish giant cell tumors that metastasized from those that did not. The mean percentage of diploid (G0/G1 peak, 2C) cells was 81% in the metastasizing group and 80% in the nonmetastasizing group. The DNA ploidy pattern of the primary tumors was not different from that of their metastases. No DNA aneuploid patterns were observed among the benign tumors.