High mast cell density indicates a longer overall survival in oral squamous cell carcinoma

This study evaluates the effects of tumour-associated mast cells on the prognosis of patients suffering from oral squamous cell carcinoma (OSCC). Tryptase-positive (MCT + ) and CD117-positive (CD117 + ) mast cells were immunohistochemically evaluated in tissue samples of 118 OSCC patients. Besides, various clinicopathological parameters, the influence of the MCT + and CD117 + mast cell density on overall survival and the incidence of first local recurrence was analysed by Cox regression and competing risk regression. Among all investigated parameters, multiple Cox regression revealed a significant influence of the MCT + (cut-off at 14.87 mast cells/mm 2 stroma; p = 0.0027) and CD117 + mast cell density (cut-off at 33.19 mast cells/mm 2 stroma; p = 0.004), the age at primary diagnosis, and the T and N stage (all p-values