Oral desmoplastic melanoma mimicking inflammatory hyperplasia.

INTRODUCTION: Desmoplastic melanoma (DM) arising in the oral cavity is a rare neoplasm that may be confused with a variety of non-melanocytic benign or malignant lesions. OBJECTIVES: To present a case of DM in the oral mucosa mimicking fibrous inflammatory hyperplasia, discusses the difficulties involved in the diagnosis and offers a literature review on the clinicopathologic and immunohistochemincal aspects of this neoplasm. CASE REPORT: A 62-year-old white male, smoker, was referred with a chief complaint of pain and swelling in the palate. The oral examination revealed multiple brown-to-black patches and a non-pigmented sessile nodule located on the mucosa of the hard palate. The clinical diagnosis of the pigmented lesions was either oral melanosis or melanoma. The nodular lesion was clinically diagnosed as fibrous inflammatory hyperplasia. Incisional biopsy was performed on the pigmented lesion and the microscopic sections revealed a melanotic macule. The nodular lesions histologically revealed an amelanotic desmoplastic melanoma. CONCLUSIONS: Reactive lesions close to a pigmented area should be investigated with great care.

Evaluation of cell proliferation rate in non-dysplastic leukoplakias

Objective: Analyze whether the most frequent cases of non-dysplastic leukoplakias, hyperkeratosis (H), acanthosis(A), and hyperkeratosis with acanthosis (HA) have similar cell proliferation rates and to compare them withepithelial dysplastic (ED) leukoplakias and normal oral epithelium (NOE).Study design: The sample comprised10 cases of normal oral epithelium, 10 cases of hyperkeratosis, 10 cases of acanthosis, 10 cases of hyperkeratosiswith acanthosis and 10 cases of epithelial dysplasia. The mean number of AgNORs per nucleus (mAgNOR) andthe mean percentage of cells with 1, 2, 3 and 4 or more AgNORs per nucleus (pAgNOR) were recorded. Results:The results of mAgNOR showed differences between disorders in the evaluation of the basal layer, of the parabasallayer, and in the overall evaluation. mAgNOR and pAgNOR=2 increased progressively from normal oralepithelium to hyperkeratosis with acanthosis, hyperkeratosis, acanthosis and epithelial dysplasia (p<0.05). Cellproliferation rate was different between different subtypes of non-dysplastic leukoplakias and this group presenteda higher proliferative behavior when compared to normal oral epithelium. Conclusion: It may be suggested thatnon-dysplastic leukoplakias had different characteristics regarding cell proliferation rates and sometimes showeda proliferative behavior similar to that found in epithelial dysplasia. More studies should be conduced to increaseknowledge about the biological profile of non-dysplastic leukoplakias, especially as it pertains to acanthosis (AU)