Sections reveal an infiltrating moderately differentiated (Grade 2) squamous cell carcinoma characterized by irregular nests of malignant squamous cells showing focal keratinization, and moderate nuclear pleomorphism with active mitosis. Separating stroma shows dense lymphoplasmacytic infiltrate. The adjacent surface mucosa exhibits full-thickness architectural loss and cytological atypia consistent with squamous cell carcinoma in situ. Tumor infiltrates skeletal muscle bundles of the tongue. Lymphovascular invasion and perineural permeation by are present.
Tongue lesion.
One soft tissue fragment measured 1.7x1.5x1.2 cm, totally embedded.
Tongue, incisional biopsy: