Discoid lupus erythematosus with squamous cell carcinoma: a case report and review of the literature in Indian patients.

We report a case of a patient with localized discoid lupus erythematosus (DLE) who was found to have high-grade squamous dysplasia (carcinoma in situ) over the upper lip. This report also consists of a brief review of 16 other cases of DLE with squamous cell carcinoma (SCC) we came across while going through the literature in an Indian scenario.Incidence of SCC over DLE in the Indian population is found to be 0.98% to 3.4% with a male-to-female ratio of 1.6:1. The latent period between onset of DLE and development of SCC was 9.59 ± 5.6 years.There was history of chronic sun exposure in 81.8% of patients, which indicates a possible role of prolonged ultraviolet light exposure in malignant transformation. The lips were the most commonly affected area (28.57%), with the upper lip being more commonly involved than the lower lip. We also observed that the latent period (5 ± 2.7 years) in lip tumours was shorter than that in other sites (11.22 ± 6.78 years), indicating a more rapid transformation in lips (p value = 0.038). Well differentiated was the most common (46.2%) type of SCC noted. Lymph node involvement was found in three of 17 cases (25%) and one case (8.3%) had recurrence of lesions after excision.We conclude that in India though SCC is rare per se, its occurrence in the context of DLE is not uncommon and is aggressive in nature.