Partialy ulcerated mucosal fragments by infiltrating nests and solid sheets of malignant squamous epithelial cells. Tumor cells exhibit marked nuclear pleomorphism, hyperchromasia, and prominent nucleoli with a abundant eosinophilic cytoplasm. Frequent mitotic figures and focal necrosis are present. Surrounding stroma shows dense desmoplastic reaction with a mixed inflammatory infiltrate.
Floor of mouth biopsy.
Soft tissue fragments collectively measured 0.8x0.5 cm, totally embedded.
Floor of mouth, biopsy: