Chondrosarcoma are rare malignant tumors. About the biological characteristics of chondrosarcoma is little-known [2]. Endothelin and its receptors are involved in regulating angiogenesis and metastatic dissemination [1]. The aim of this study is first to identify if chondrosarcoma are expressing endothelin-1 (ET-1) and the endothelin-receptors and thereupon to identify potential molecular markers for new target therapies. Another aim is to determine if endothelin is a prognostic factor in chondrosarcoma.

32 cases were investigated clinically and histopathologically. The expression of vascular endothelial growth factor (VEGF), Endothelin-1, Endothelin-Receptor-A (ETR-A) and Endothelin-Receptor-B (ETR-B) were determined. All data were analyzed by Fisher’s exact test (p< 0,05). All tumors show an expression of either ET-1, ETR-A or ETR-B. Chondrosarcomas with grade (G) I are mostly expressing less than 10-% ET-1 in cells, Chondrosarcomas G II are expressing in most cases between 10–50% and nearly all Chondrosarcoms G III more than 50%. In addition ET-1-expression is correlating with the histological grading. The patients also show a significant high metastatic dissemination probability at the time when tumor samples present more than 10%-storing ET-1-cells. The intensity of ET-1-expression is correlating with VEGF, which is the most important angiogenetic factor in tumors.

Chondrosarcomas are expressing ET-1, ETR-A and ETR-B. ET-1 seems to play a role in the angiogenesis of chondrosarcoma. Increased expression of ET-1 is accompanied with a high probability of metastatic dissemination. Endothelin receptor antagonists, which are used for example in prostate and breast cancer, can represent a potential therapy for chondrosarcoma [1]. Experiments on animals and clinical studies are required.