An analysis of rate and factors affecting malignant transformation of oral submucous fibrosis in patients attending the Oral Medicine Clinic, Dental Hospital Peradeniya, Sri Lanka - A retrospective study

Background: Oral submucous fibrosis (OSF) is a chronic, progressive, scarring and potentially malignant disease of the oral mucosa seen primarily in the Indian subcontinent and in South East Asia. OSF is a premalignant condition with a malignant transformation rate varying from 7-12%. Even though OSF and oral cancer are common in Sri Lanka, malignant transformation potential and rate have not been studied in our population.

Objectives: To identify the relationship of malignant transformation with age, gender, habits, amount of mouth opening, duration of follow up, presence of other oral potentially malignant disorders and dysplasia in a group of patients with OSF attending the Oral Medicine clinic, University Dental Hospital Peradeniya.

Methods: All the clinical files of patients with OSF attending the Oral Medicine clinic, University Dental Hospital Peradeniya were selected. Cases with OSF where histopathological diagnosis was not available, patients who had developed oral cancer before the diagnosis of OSF and patients who were diagnosed with OSF and received prior surgical therapy were excluded. Data were analysed to identify any relationship of malignant transformation with other variables.

Results: There were 135 patients with a follow up period ranging from 6 months to 23 years and average follow up period was 5.26 years. 75.6% of them were males. 42.2% of them presented with burning sensation as the main complaint. 96.3% of them chewed betel with all ingredients whereas the rest chewed only arecanut. Eight patients developed malignancy during the follow up period giving a malignant transformation rate of 5.9% after a mean follow up period of 6.5 years.

Conclusions: Malignant transformation in patients with OSF is significantly associated with presence of dysplasia on the initial biopsy, presence of any other potentially malignant disorder and the duration of betel chewing.