ABSTRACT
OBJECTIVE: Small cell carcinoma has the worst prognosis of all laryngeal neoplasms. In order to further characterise this tumour, with a view to development of new therapeutic approaches, we report the results of KIT gene and platelet-derived growth factor receptor α gene expression analysis, for two extremely rare cases of primary small cell carcinoma of the larynx. METHOD: Case reports, including immunohistochemical study, and review of the literature. RESULTS: We present two patients with laryngeal small cell carcinoma, who died from tumour metastasis to the lungs and brain despite aggressive treatment. Immunohistochemical studies revealed positive reactions for KIT gene expression and platelet-derived growth factor α gene expression in patient one, and for KIT gene expression in patient two. Molecular genetic analysis, using polymerase chain reaction direct sequencing, identified no mutations of the KIT or platelet-derived growth factor receptor α genes. CONCLUSION: Although further investigation is necessary regarding KIT gene expression and platelet-derived growth factor receptor α gene expression in laryngeal small cell carcinoma, the reported results suggest that these genes may be significant in the development of molecular targeted therapy.