Dr. Rupak Sethuraman

SPECIFIC LEARNING OBJECTIVES To learn the common white lesions of the oral mucosa. To learn the etiopathogenesis, clinical features, investigations and treatment for oral leukoplakia.

FORMAT Some common white lesions of the oral cavity Etiopathogenesis of oral leukoplakia Investigations and treatment for leukoplakia

COMMON WHITE LESIONS Leukoedema Linea Alba Buccalis Chemical injuries of the oral mucosa Candidiasis Oral Leukoplakia Oral Submucous fibrosis Oral Lichen Planus

Leukoplakia (leuko-white; plakia-patch) Oral leukoplakia is defined by the WHO as “a white patch or plaque that cannot be characterized clinically or pathologically as any other disease”. Thus a diagnosis by exclusion. The term is strictly a CLINICAL one and does not imply a specific histopathologic tissue alteration. Leukoplakia is the most common oral precancer.

Leukoplakia: Why is it White? The clinical color (white) results from a thickened surface keratin layer (which appears white when wet) and/or a thickened spinous layer, which masks the normal vascularity (redness) of the underlying connective tissue.

Leukoplakia: A Premalignant or Precancerous Lesion Although leukoplakia is not associated with a specific histopathologic diagnosis, it is considered to be a premalignant lesion for the risk of malignant transformation is greater in a leukoplakic lesion than that associated with normal or unaltered mucosa.

Despite the fact that leukoplakia is a premalignant lesion it should be noted that not every lesion shows histopathologic evidence of epithelial dysplasia or frank malignancy (squamous cell carcinoma). In fact, dysplastic epithelium or invasive carcinoma is found in only 5 to 25 % of the biopsy samples of leukoplakia.

Leukoplakia: Malignant Transformation Potential Overall, the malignant transformation potential of leukoplakia is 4 % (estimated lifetime risk). However, specific clinical subtypes are associated with much higher potential malignant transformation rates (as high as 47 %).

Etiology of Leukoplakia: The Role of Tobacco The habit of tobacco smoking appears most closely associated with leukoplakia development. 80 % of patients with leukoplakia are smokers. Smokers are much more likely to have leukoplakia than non-smokers.

Heavier smokers have greater numbers of and larger lesions than light smokers. A large proportion of leukoplakias in persons who stop smoking either disappear or become smaller soon after discontinuing the habit.

Candida albicans has been demonstrated histologically in the hyperplastic/dysplastic epithelium of lesions termed candidal leukoplakia and candidal hyperplasia. Human papillomavirus (HPV), particularly subtypes 16 and 18, have been identified in some oral leukoplakias.

Leukoplakia: Clinical Features Leukoplakia usually affects people over the age of 40 years (average age is 60 years). Prevalence increases rapidly with age particularly in males. Approximately 8 % of the males over the age of 70 years are reportedly affected. Approximately 70 % of the oral leukoplakias are found on the lip vermilion, buccal mucosa and gingiva.

Leukoplakia: Clinical Features Continued Early/mild thin leukoplakia, which seldom shows dysplasia on biopsy, may disappear or continue unchanged. If the cause (s) of the lesion are not removed, many lesions will gradually become thicker and larger.

INVESTIGATIONS Toluidine blue staining followed by biopsy to look for dysplastic features.

Leukoplakia: Treatment and Prognosis Treatment depends upon the diagnosis and any leukoplakia exhibiting moderate epithelial dysplasia or worse warrants complete removal if possible. Treatment of lesions exhibiting less severe changes is guided by the size of the lesion and its response to more conservative measures such as eliminating tobacco use.

VARIOUS TREATMENT MODALITIES 1. Carotenoids- Antioxidant action Beta Carotene 20-90mg/day for 3-12 months Lycopene 4-8 mg/day for 3 months 2. Vitamins Vitamin A, E and C 3. Topical Bleomycin 0.5% per day for days or 1% per day for 14 days 4. Photodynamic Therapy

Leukoplakia: Treatment and Prognosis Continued Leukoplakia not exhibiting dysplasia often is not excised but clinical evaluation every 6 months is recommended. Additional biopsies are recommended if smoking continues or if clinical changes increase in severity.

Thank you Any questions???