Abstract: Objective To investigate the relationship between the morphology and content of collagen fibers and the development of tumor in human oral squamous carcinoma. Methods Paraffin sections from the 80 clinical specimens of oral squamous cell carcinoma that were stained with HE and Masson’s trichrome stain were observed for collagen fibers under the microscope. Statistical analysis was used to analyze the expression of collagen fiber and its correlation with tumor differentiation. Results Oral submucous fiber deposition was observed in severe atypical hyperplasia. The morphology and distribution of collagen fibers obviously decreased in infiltrating carcinoma with different invasiveness as well as in highly, moderately and lowly differentiated carcinomas. The difference in collagen per area among groups was statistically significant (P<0.05), and the tumor differentiation degree was negatively related to the tumor progression(r=-0.800, P<0.05). Conclusion The distribution and morphology of collagen fibers are closely related to the development of human oral mucous carcinoma and the differentiation degree of carcinomas. 

Key words: collagen fiber, carcinoma of oral mucous, Masson’s trichrome stain