Expression of type III collagen correlates with poor prognosis in oral squamous cell carcinoma.

AIM: The aim of the present study was to evaluate, compare, and correlate the types of collagen fibers seen in different grades of oral cancer. METHODS: Thirty cases of histologically-diagnosed, well-, moderately-, and poorly-differentiated oral squamous cell carcinoma (OSCC) were retrieved from the archives of the Institute. Collagen was evaluated using picrosirius red stain and immunohistochemical analysis of the antibody to type III collagen. A correlation between these findings and the grade of OSCC was evaluated. RESULTS: Collagen fibers showed a change in birefringence ranging from reddish-orange to greenish-yellow in well- to poorly-differentiated oral squamous cell carcinoma. The findings were statistically significant for polarizing colors observed in grades of OSCC (P<.001). Immunohistochemical staining intensity of type III collagen changed from weak to strong as grade increased for OSCC, and was also statistically significant (P<.001). CONCLUSION: In the present study, tumor progression reflected a change in collagen present, from type I to type III. Determination of the type of collagen in different grades of OSCC can facilitate therapeutic targeting of molecules responsible for invasion and progression of oral cancer.