Isolated intra-oral granular cell tumor: report of two cases and review of the literature

ABSTRACT

Granular cell tumor (GCT) is a relatively uncommon lesion occurring in almost any part of the body, including the orofacial region. The tongue and the buccal mucosa are common intra oral sites. Although aggressive and malignant variants of this neoplasm have been described, most GCTs are benign. The histogenesis of the lesion still remains unknown. However, histochemical and ultra-structural studies propose the origin of the lesion from Schwann cells, striated muscle, mesenchymal cells, histiocytes and epithelial cells. The tumor generally occurs in middle-aged or older adults. The lesion is typically seen as an uninflamed asymptomatic mass measuring about two cm in diameter with reddish surface coloring. As most granular cell tumors are benign, surgical excision of the lesion is the treatment of choice. In this study, 2 oral GCT cases are presented, corresponding to 2 male patients, with a mean age of 27 years and a mean time of evolution of the lesions of 8 months. Both lesions were located on the tongue. Differential diagnoses include fibrous hyperplasia, minor salivary gland tumor, condyloma acuminatum and neurilemmoma. In all the cases a resection with safety margins of the lesions was carried out under local anesthesia. The samples were fixed and processed for histopathological study. The main clinical pathology and diagnostic features of this neoplasm are reviewed and discussed.

RESUMO

O tumor de celulas granulares (TCG) e uma lesao relativamente incomum que pode acometer qualquer parte do corpo, incluindo a regiao buco-maxilo-facial. A lingua e a mucosa bucal sao localizacoes intraorais comuns. Embora casos de transformacoes malignas e agressividade terem sido descritos, a maioria dos TCG sao benignos. A histogenese desta lesao continua desconhecida. No entanto estudos de imunohistoquimica e ultraestruturais sugerem que a lesao se origina das celulas de schwann, musculatura estriada, celulas mesenquimais, histiocitos e celulas epiteliais. O tumor geralmente ocorre na meia idade ou em pacientes idosos. A lesao e tipicamente vista como uma massa assintomatica nao inflamatoria que mede cerca de dois centimetros de diametro com uma superficie de coloracao avermelhada. A maioria dos tumores de celulas granulares sao benignos cuja excisao cirurgica e o tratamento de escolha. Neste estudo, 2 casos orais de TCG sao apresentados sendo ambos em pacientes do sexo masculino, com media de idade de 27 anos e tempo medio de evolucao da lesao de 8 meses. A localizacao de ambas as lesoes foi o dorso da lingual. O dignostico diferencial incluiu a hiperplasia fibrosa, tumor de glandulas salivares menores, condiloma aculminado e neiurilenoma. Em todos os casos a resseccao com margens de seguranca foi realizado sob anesthesia local. As amostras foram fixadas e processadas para o estudo histopatologicos. As principais caracteristicas clinicopatologicas e de disgnostico foram revisadas e discutidas.