PIGMENTED SQUAMOUS CELL CARCINOMA IN THE ORAL CAVITY: A CASE REPORT AND HISTOCHEMICAL ANALYSIS

• Published in: Oral surgery, oral medicine, oral pathology and oral radiology Vol. 130; no. 3; p. e152
• Main Authors: COLTURATO, CARLA BENTO NELEM, DOMINGUETE, MATHEUS HENRIQUE LOPES, DOMINGUETE, KAMILA PRADO PEREIRA GRACIANO, SILVEIRA, HEITOR ALBERGONI DA, ALMEIDA, LUCIANA YAMAMOTO, RIBEIRO-SILVA, ALFREDO, LEÓN, JORGE ESQUICHE
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01-09-2020
• ISSN: 2212-4403; 2212-4411
• DOI: 10.1016/j.oooo.2020.04.202

Squamous cell carcinoma (SCC) is the most frequent malignant neoplasm of the oral cavity. SCC presents several histologic variants, such as clear cell, signet-ring, basaloid, desmoplastic, verrucous, cuniculatum, lymphoepithelial, and pigmented. This latter is a rare variant of oral SCC. We present a case of pigmented oral SCC, emphasizing its differential diagnosis. A 60-year-old male patient was referred presenting with a nodular lesion, reddish coloration, 3 cm in diameter, asymptomatic, and arising from the lateral border of the tongue. Microscopically, typical SCC was revealed, and in addition to the tumor cells, dendritic cells with dark intrinsic pigments were found surrounding the tumor cells. The pigments were negative for Ziehl-Neelsen and periodic-acid Schiff stains, and positive for Fontana-Masson stain. To date, only 16 cases of pigmented oral SCC have been reported, with variable clinical presentation despite detection of melanin in these tumors.