Oral submucous fibrosis as a precancerous condition.

An evaluation of the malignant potential of submucous fibrosis, based on observations of 89 patients with the disease in Ernakulam District, Kerala, India was done. Out of the 89 patients, 12 were referred patients and 77 were diagnosed in population based studies. At the time of first examination oral cancer was found to be coexistent in nine (10%) cases. For 66 patients follow-up observations ranging from 4 to 15 yr (median 8 yr) were available. During this period malignant transformation was observed in three patients (4.5%). Considering malignant transformation and coexistence together, oral cancer was observed in 13% of the present material. Leukoplakia was found in 26% of the patients with submucous fibrosis. Out of 42 submucous fibrosis patients biopsied, 12% showed squamous cell carcinoma, 26% epithelial dysplasia, and 76% atrophic epithelium. These findings reinforced the hypothesis that submucous fibrosis is a precancerous condition.