Potential for Using EGFR Expression in Rhabdomyosarcoma, Osteosarcoma and Ewing’s Sarcoma: Clinicopathological and Prognostic Significance

Abstract

Sarcomas are a heterogeneous group of malignant tumors that arise from mesenchymal cells and can arise anywhere in the body, whether it is soft tissue or bone. Epidermal growth factor receptor (EGFR) expression in pediatric sarcomas is explored in the current study. A key feature of EGFRs is their general involvement in signal transduction and oncogenesis, making them one of the most studied receptor protein-tyrosine kinase families. The study included 104 archived formalin-fixed paraffin-embedded blocks assessed using immunohistochemical stains for EGFR expression in rhabdomyosarcoma, osteosarcoma, and Ewing's sarcoma. EGFR gene copy number was analyzed by dual silver in situ hybridization (DISH). EGFR was positively expressed in 56.7% of pediatric sarcoma. Immunostaining for EGFR was significantly associated with deep large tumors, stage, and histologic grade. Significantly, lower chances of overall survival were observed with elevated levels of EGFR five years post-diagnosis. EGFR staining identified independent risk factors for poor patient outcomes. The results of in situ hybridization did not indicate EGFR gene amplification in any of the cases assessed. EGFR overexpression was an independent predictor of pediatric sarcoma outcome, which is highly associated with histologic grade and stage. Results indicate EGFR inhibitors should be potentiated and directed against pediatric sarcoma. KEYWORDS EGFR, Ewing’s sarcoma, osteosarcoma, rhabdomyosarcoma