1. Oral squamous cell carcinoma

2. A malignancy of epithelial cells Oral and oropharyngeal SCC represent about 3% of cancers in men and 2% of cancers in women. Approximately 94% of all oral malignancies the risk of intraoral cancer increases with increasing age, especially for males. male-to-female ……..3: 1

3. an accumulation of several of various genetic aberrations is necessary before the affected cell expresses a malignant phenotype

4. Loss of cell cycle control increased proliferation reduced apoptosis

5. Histopathologic Features

6. SCC arises from dysplastic surface epithelium Epithelial dyplasia abnormal changes in the size, shape, and organization of mature cells

8. invasive Individual squamous cells, islands and cords of malignant squamous epithelial cells within the connective tissues.

9. 1. Enlarged nuclei and cells 2. Large and prominent nucleoli 3. Increased nuclear-to-cytoplasmic ratio Hyperchromatic (excessively dark-staining) nuclei 4.Pleomorphic nuclei and cells 5. Dyskeratosis (premature keratinization of individual cells ) 6.Increased mitotic activity ( excessive numbers ofmitose S ) 7. Abnormal mitotic figures (tripolar orstar mitoses, or mitotic figures above the basal layer CYTOLOGIC CHANGES

11. STRUCTURAL CHANGES 1. Bulbous or teardrop-shaped rete ridges 2. Loss of polarity (lack of progressive maturation toward the surface) 3. Keratin or epithelial pearls (focal, round c ollections of concentrically layered keratinized cells) 4.Loss of typical epithelial cell cohesiveness

12. grading the degree to which these tumors resemble their parent tissue and produce their normal product (keratin)

13. well-differentiated SCC mature enough………. closely resemble its tissue of origin Keratin production

15. Poorly differentiated SCC

16. moderately differentiated carcinoma mitoses malignant cells are still easily recognizable as being of squamous epithelial origin no keratinization

17. Metastasis spread of oral squamous cell carcinoma is largely through the lymphatics to the ipsilateral cervical lymph nodes

18. Lymph Node Metastasis This is a cervical lymph node showing focal areas of metastatic squamous carcinoma.