Solitary Fibrous Tumor of Retromolar Pad; a Rare Challenging Case.

Solitary fibrous tumor has a wide spectrum of histopathologic features and many tumors show similar microscopic features. This similarity poses diagnostic challenges to the pathologists and immunohistochemical analysis is required in many cases. Moreover, it is a rare entity in orofacial region which consequently would make its diagnosis more challenging in oral cavity. The knowledge of various microscopic patterns of this tumor contributes to a proper diagnosis and prevents unnecessary treatment. This study reports a case of solitary fibrous tumor in the retromolar pad area and discusses its various histological features and differential diagnoses.

Combined Analysis of Vascular Endothelial Growth Factor Expression with Cyclooxygenase-2 and Mast Cell Density in Oral Squamous Cell Carcinoma.

BACKGROUND: Overexpression of vascular endothelial growth factor (VEGF) and cyclooxygenase-2 (COX-2) and increasing mast cell density (MCD) in premalignant and malignant oral lesions have been documented. However, their correlation with clinicopathologic parameters and survival rate in oral squamous cell carcinoma (OSCC) is not completely clear. This study aimed to assess these subjects. METHODS: VEGF, COX-2, and mast cell tryptase expression were examined immunohistochemically in 57 cases of OSCC. The relationships between the markers' expression and clinicopathologic data were assessed using bivariate and multivariate analysis. RESULTS: Spearman's rank correlation coefficient showed a significant correlation between VEGF and COX-2 expression (r = 0.462, p < 0.001), as well as between VEGF expression and MCD (r = 0.306, p < 0.001). Multivariate analysis showed no significant correlation between the markers' immunoexpression and overall survival (OS), but a significant correlation between mode of invasion and OS [hazard ratio 0.362 (95% CI: 0.138- 0.974); p = 0.038] was observed. An association between MCD and gender (p = 0.042) was also found, as MCD was higher in males. CONCLUSION: The significant correlation of VEGF expression with COX-2 expression and MCD may represent the roles of COX-2 and MCD in tumor angiogenesis by modulating VEGF production. However, VEGF, COX-2, and MCD are not useful indicators to predict prognosis in OSCC. Nevertheless, the mode of invasion can be considered as an independent prognostic factor in OSCC patients.