Which of the following produces pre-malignant lesions -: (A) Psoriasis, (B) Erythema multiforme, (C) Lichen planus, (D) All of the above
Answer is C. Ans is 'c' i.e. Lichen planus "Oral LP, particularly the erosive (ulcerative variant) is prone to develop SCC, the frequency being 0.8%. Long standing disease and concurrent use of tobacco are the risk factors for malignant transformation. Tongue is the most common site for malignancy, followed by buccal mucosa." - IADVL text book of dermatology 3rd/e p. 1074