Prognostic value of DNA ploidy response to chemotherapy in human osteosarcomas

We analyzed the DNA ploidy alterations after preoperative chemotherapy in 3 0 patients with non-metastatic osteosarcomas of the extremities. All of the patients received intensive chemotherapy with doxorubicin, cisplatin and m ethotrexate as well as wide tumor resection. DNA ploidy was determined by D NA cytofluorometry using isolated and smeared cells from biopsied and resec ted tumors after preoperative chemotherapy. The results showed that 12 dipl oid and nine non-diploid osteosarcomas did not change their ploidy pattern, but nine non-diploid tumors changed to a diploid pattern with the disappea rance of the aneuploid cells. The nine patients with altered ploidy tumors had a better histologic response to chemotherapy and a better prognosis tha n the patients with non-altered tumors especially diploid tumors (P = 0.013 8). Therefore, we conclude that a decrease in aneuploid cells after chemoth erapy is closely correlated with a good prognosis in half of the cases of a neuploid osteosarcoma. These results also suggest that aneuploid cells are more chemosensitive than diploid cells in human osteosarcomas. (C) 1999 Els evier Science Ireland Ltd. All rights reserved.