20 March 2019

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A large neoformation in the right emipalate

Co-authors: A. Khalil, L. Moneghini, A. Pispero

Giovanni Lodi

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A 37-year-old male patient arrived at our observation at the Service of Pathology and Oral Surgery of the Operative Unit of Odontostomatology II of ASST Santi Paolo e Carlo, complaining of the presence of an asymptomatic mass at the level of the emipalate of right (fig. 1). The patient, smoker and occasional drinker, reported only medical allergic rhinitis (hay fever) and denied taking medication on a regular basis. The patient reported that the lesion had formed slowly, over a period of about 10 years, without this being accompanied by any symptoms. The outcome of the tests he carried with him (OPT and CT cone beam) did not show any bone resorption in the area affected by the lesion. At the intraoral objective examination there was a firm mass of increased consistency, which involved the entire molar area of ​​the right maxilla, covered by a normal oral mucosa with darker areas. The dental elements were all vital. The lesion did not appear to be on palpation and showed no particular signs of inflammation or infection. 
Based on the clinical features, the lesion was placed in differential diagnosis with the pleomorphic adenoma, mucoerpidermoid carcinoma, squamous cell carcinoma, reactive fibrosis, non-Hodgkin's lymphoma and giant cell granuloma. It was therefore considered necessary to obtain a histological diagnosis capable of establishing the exact nature of the new formation. According to the patient and after perilesional local anesthesia, an incisional biopsy was performed using a 6 mm punch scalpel. The material taken was oriented on paper, immersed in a fixative liquid and sent to the pathological anatomy laboratory. The histopathological examination of the neoformation allowed the diagnosis of intramucosal nevus (fig. 2). 
Intramucosal nevus is a benign proliferation of melanocytes associated with an increase in melanin content. Most oral snows appear around the age of 30-40 with a preference for the female sex and for the mucous membrane of the palate and gum. The appearance is that of a localized hyperpigmentation, whose color can vary from dark brown to black or dark blue. Snows, compared to melanitic macules, have the characteristic of being slightly raised. In the case of mucous nevus, the snow cells are formed in the context of the lamina propria without connection with the basal cell layer (fig. 3). They present a round and light-colored cytoplasm; contain more or less dense granules of melanin. Intramucosal nevus is the most frequent form of nevus of the oral mucosa.