Background: A variety of molecular markers related to survival, have been studied in a variety of human neoplasms, particularly in carcinomas, but their significance in osteosarcoma patients is largely unknown. The purpose of this archival study was to determine if there is a correlation between their expression and disease-free and overall survival for patients with osteosarcoma.

Materials and Methods: 93 patients with stage IIB osteosarcomas originating around the knee (distal femur and proximal tibia)were studied. Tumors were evaluated with antibodies to Bcl-2, p53, Fas, Fas L, CD44s, CD44v6, and P-glycoprotein using standard avidinbiotin complex methods. Expression of the various antigens was statisticaly compared to disease-free and overall survival.

Results: Fas (p< 0.05) and Cd44v6 (p< 0.03), were significant and related with the purpose of study; P-glycoprotein was near and the others with no significance.

Conclusions: Fas appears to have a “protective” function in osteosarcoma, probably by allowing tumor cells to proceed through apoptosis pathway to cell death. Although CD44v6, a vascular adhesion molecule, was identified in only 14% of the total cases, its expression correlated with subsequent development of metastases and death (11 of the 13 patients developed pulmonary metastases dying of disease). Although P-glycoprotein did not reach significance, there was a trend toward death from disease in patients expressing it.