ASSESSMENT OF CHEMOSENSITIVITY IN PATIENTS WITH OSTEOGENIC-SARCOMA USING THE DOXORUBICIN BINDING ASSAY

Background and Objectives: Assessment of chemosensitivity in patients with osteosarcoma may help identify those with resistance to chemother apy. In this study, wt: investigated the clinical value of the doxorub icin binding assay in its ability to identify patients with drug resis tance. Methods: We tested tumor tissue samples obtained at biopsy of 2 4 patients with high-grade osteosarcoma aged 9-61 years (mean 19.2) fo r sensitivity to doxorubicin, using the doxorubicin binding assay. Tum or excision was performed in these patients after neoadjuvant chemothe rapy. Chemotherapy response was judged on the basis of tumor necrosis achieved and was compared with doxorubicin sensitivity in each of thes e patients. Results: Doxorubicin sensitivity was good in 15 and poor i n 9 of 24 patients studied. In patients with good sensitivity (n = 15) , 9 (60%) exhibited a good response to chemotherapy while response was poor in 6. In patients with poor sensitivity (n = 9), response to che motherapy was poor in all 9 (100%) patients and 7 (77.8%) of these pat ients developed metastatic disease within a mean period of 5.2 months, resulting in two deaths. The results were statistically significant a t P = 0.0193. Conclusions: Doxorubicin binding assay may be useful in identifying patients with inherent resistance to chemotherapy. As the outcome of patients showing resistance to doxorubicin is poor, innovat ive strategies may need to be developed for this group of patients. (C ) 1998 Wiley-Liss, Inc.