Immunohistochemical characterization of feline oral squamous cell carcinoma

Objective-To evaluate the expression of Ki67 and epidermal growth factor receptor (EGFR), mitotic index (MI), and microvascular density (MVD) in feline oral squamous cell carcinoma (SCC) via immunohistochemical staining on archival tumor tissues and to seek a correlation between these markers and clinical variables. Sample-22 archived tumor samples of feline oral SCC. Procedures-Immunohistochemical staining for Ki67, MVD, and EGFR was performed and scored. Patient survival information was obtained from the medical records. These molecular markers as well as MI were correlated with tumor locations and patient survival time. Results The 22 tumors had wide variation in Ki67 expression, MI, MVD, and EGFR expression. Tongue SCC had higher MVD than did mandibular and maxillary SCC. Tumor expression of EGFR was inversely proportional to survival time. Conclusions and Clinical Relevance-Results suggested that EGFR expression might be a valuable prognostic factor for treatment outcome in feline oral SCC. It also identified higher angiogenesis in tongue SCC, compared with mandibular and maxillary SCC, which may account for a different clinical outcome. Further prospective characterization of feline oral SCC may provide a better understanding of the underlying molecular factors that drive its behavior and offer the possibility for future patient-specific treatment plans. (Am J Vet Res 2012;73:1801-1806)