Tumeur cutanée à cellules granuleuses

La tumeur à cellules granuleuses ou tumeur d’Abrikossoff est une tumeur bénigne rare qui siège principalement au niveau de la tête et du cou avec atteinte préférentielle de la muqueuse buccale. Deux fillettes âgées de 8 et 12 ans, sans antécédent, présentaient des lésions nodulaires pigmentées siégeant respectivement au niveau de la région scapulaire gauche et en regard de la crête iliaque gauche. L’examen histologique et l’étude immuno-histochimique de la biopsie cutanée confirmaient le diagnostic de tumeur à cellules granuleuses. Dans les 2 cas, une exérèse chirurgicale avec des marges de 2 cm était réalisée. Aucune récidive n’était notée après un recul de 6 et 2 mois. La tumeur d’Abrikossoff est une tumeur d’origine schwannienne prédominant normalement chez les femmes de race noire, âgées de 20 à 60 ans et siégeant principalement au niveau de la muqueuse buccale. L’atteinte de l’enfant est plus rare et exceptionnelle dans sa forme cutanée pure. L’histologie montre une prolifération de cellules de grande taille à cytoplasme abondant granulaire et à noyaux de petite taille, hyperchromatiques et réguliers. En immuno-histochimie, les cellules tumorales expriment la protéine S100, la neuron specific enolase (NSE) et la vimentine. Le traitement consiste en une exérèse complète afin d’éviter la récidive.Granular cell tumor (GCT), also known as Abrikossoff tumor, is a rare and benign neoplasm that more commonly affects the oral cavity in adults. We report here 2 childhood cases of a cutaneous granular cell tumor.An 8- and a 12-year-old girl, with no past medical history, presented with pigmented nodular lesions located, respectively, in the left scapular region and the left iliac crest. Histological examination showed sheets and clusters of infiltrating tumor cells with morphologic and immunohistochemical features consistent with granular cell tumor. In both cases, the lesions were excised with 2-cm margins. The patients are presently being reviewed at 6-month and 2-month intervals to evaluate for recurrence and any malignant transformation. They were in good health with no signs of further tumor development.GCT is a relatively uncommon benign neoplasm probably of neural origin derived from Schwann cells. The tongue and buccal mucosa are commonly affected. It develops between the second and sixth decades of life, more frequently among women and blacks. It can also occur in childhood, but this is rare. The cutaneous forms, as in the present observations, are exceptional. Benign granular cell tumours are generally seen as a solitary asymptomatic nodule less than 3 cm in size involving the subcutaneous or submucosal tissues. Histologically, the tumor is not encapsulated but is well circumscribed. The tumor cells may show a degree of infiltration of the surrounding connective tissue. The cells are polygonal, have abundant cytoplasm, are granular and weakly eosinophilic. The nuclei are small, vesicular, and highly chromatic. Mitotic figures are rare. A key element for the histological diagnosis is the expression of S100 protein, neuron specific enolase (NSE), and vimentin on immunohistochemistry. The treatment of choice is a conservative surgical excision of the lesion. However, as the GCT has a poorly defined margin, it is suggested that the tumor should be excised along with portions of adjacent tissue. A low rate of recurrence of the lesion has been reported.The specific value of these rare cases is the occurrence in 2 children and the cutaneous location.