P-GLYCOPROTEIN EXPRESSION: CRITICAL DETERMINANT IN THE RESPONSE TO OSTEOSARCOMA CHEMOTHERAPY

摘要: Background: Fewer than 20% of patients with bone cancer who are treated surgery alone cured. Even the best current treatment, combined chemotherapy, only 60%-80% nonmetastatic and 10% metastatic Thus far, reason for treatment failure in non-responding subset has not been identified. It hypothesized that P-glycoprotein, which confers multidrug resistance, might be cause. We sought to determine whether expression P-glycoprotein is associated poor outcome osteosarcoma. Methods: In a retrospective study, we correlated conventional chemotherapy 62 consecutive, clinically staged diagnosed as having osteosarcoma between 1980 1989. Results: was overexpressed 27 but another 34 patients, ambiguous sample from one patient. At median follow-up 8.9 years, whose tumors did express had significantly better relapse-free rates subjects expressed protein (87% versus 0%; P<.00001) improved survival (94% 35%; P<.00001). Among 46 received before surgery, 23 were negative showed long-term outcomes (P<.00002), although differences tumor necrosis response therapy borderline significance (P = .057). Conclusions: does correlate This correlation raises possibility inhibiting action part this disease would improve outcome.