title: Oral squamous cell carcinoma arising in background of oral submucous fibrosis: a clinicopathologically distinct disease.
abstract: BACKGROUND
  Oral cancer is the most common cancer in Indian males and is the third most common cancer in Indian females. Tobacco, alcohol, areca nut, and human papillomavirus (HPV) are the common etiologic factors. Each of these agents follows a unique model of carcinogenesis that leads to a certain distinct presentation and behavior. For example, HPV is strongly associated with oropharyngeal cancers in younger age and is known to have a better outcome and specific histopathologic characteristics. A high incidence of oral submucous fibrosis (OSMF) is linked to areca nut (group 1 human carcinogen) chewing in the Indian subcontinent.
  
  
  METHODS
  We prospectively studied 371 consecutive patients with proven squamous cell carcinoma of the oral cavity. Of these, 112 patients had oral cancer with OSMF and 259 had oral cancer without OSMF. All patients underwent standard management and their clinicopathologic findings were recorded.
  
  
  RESULTS
  We found that patients of oral cancer with OSMF are younger males with better prognostic factors such as better grade of tumor differentiation, lesser incidence of nodal metastases, and extracapsular spread. This difference was maintained even after matching for stage. We also report that presence of OSMF is an independent factor influencing nodal metastases.
  
  
  CONCLUSIONS
  Based on these findings we propose that oral cancers with OSMF constitute a clinicopathologically distinct disease. Since all patients with OSMF had chewed areca nut with or without smokeless tobacco, we believe that the differences in the 2 groups emanate from differential mechanisms of areca nut carcinogenesis.
authors.affiliation: Department of Head and Neck Oncosurgery, Tata Memorial Hospital, Parel, Mumbai, Maharashtra, India.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Chaturvedi
authors.forename: Sagar S
authors.initials: SS
authors.lastname: Vaishampayan
authors.forename: Sudhir
authors.initials: S
authors.lastname: Nair
authors.forename: Deepa
authors.initials: D
authors.lastname: Nair
authors.forename: J P
authors.initials: JP
authors.lastname: Agarwal
authors.forename: S V
authors.initials: SV
authors.lastname: Kane
authors.forename: Prashant
authors.initials: P
authors.lastname: Pawar
authors.forename: Sourav
authors.initials: S
authors.lastname: Datta
mesh_terms: D000328:Adult; D017677:Age Distribution; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology*; D015984:Causality; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000473:pathology*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D009914:Oral Submucous Fibrosis / Q000453:epidemiology* / Q000209:etiology / Q000473:pathology*; D011230:Precancerous Conditions / Q000453:epidemiology / Q000473:pathology*; D011379:Prognosis; D018570:Risk Assessment; D017678:Sex Distribution; D012907:Smoking / Q000009:adverse effects; D016019:Survival Analysis; D014030:Tobacco, Smokeless / Q000009:adverse effects / Q000706:statistics & numerical data