RESUMO O xantogranuloma juvenil é uma patologia histiocítica benigna rara. A manifestação clínica ocorre geralmente até os 2 anos de idade com pápulas amareladas e evolução clínica variável. Cerca de 0,75% dos pacientes apresentaram comprometimento sistêmico e 0,25%, comprometimento ocular. O objetivo deste relato é descrever o caso de uma pré-escolar de 2 anos do sexo feminino, com nodulação em pálpebra superior direita, 0,5cm de base e bordos bem definidos, data de início não estimada, mas crescimento estável há 6 meses, sem sinais flogísticos, prurido, dor, sangramentos ou outras lesões similares no corpo. Sem mais alterações ao exame físico. A análise histopatológica da peça evidenciou lesão cutânea com células histiocitoides, fusiformes e outras xantomizadas; infiltrado inflamatório de permeio e numerosas células gigantes do tipo Touton, resultado compatível com o diagnóstico de xantogranuloma juvenil. Assim, ressalta-se a importância da inclusão do xantogranuloma juvenil no diagnóstico diferencial de lesões palpebrais, especialmente em crianças.

ABSTRACT Juvenile xanthogranuloma is a rare benign non-Langerhans cell histiocytosis. Clinical manifestation usually occurs up to the age of 2 years, with yellowish papules and variable clinical progression. Approximately 0.75% of patients had systemic involvement and 0.25%, ocular alterations. The purpose of this report is to describe a case of a preschool 2-year-old female patient, with nodules in the upper right eyelid, 0.5-cm wide, with well-defined edges, an uncertain date of onset, a stable growth for 6 months, with no inflammatory signs, pruritus, pain, bleeding, or other similar lesions in the body. No further changes were observed in the physical examination. Histopathological examination of the specimen showed a skin lesion with histiocytoid, spindle-shaped cells and xanthomized cells, inflammatory infiltrate and numerous Touton giant cells. The result was compatible with diagnosis of juvenile xanthogranuloma. Therefore, the importance of including juvenile xanthogranuloma in the differential diagnosis of eyelid lesions is emphasized, especially in children.

Pleomorphic adenoma (PA), the most common salivary gland tumor, accounts for 54 to 65% of all salivary gland neoplasias and 80% of the benign salivary gland tumors. It most frequently affects the parotid gland, followed by the submandibular and the minor salivary glands. Microscopically, mucous, sebaceous, oncocytic and squamous metaplasia, sometimes with the formation of keratin pearls, may be present, but the latter rarely results in the formation of extensive keratin-flled cysts lined by squamous epithelium. Extensive squamous metaplasia can be mistaken for malignancy, including mucoepidermoid carcinoma and squamous cell carcinoma. Here, we present an unusual case of PA with extensive squamous metaplasia and keratin cyst formations in a minor salivary gland, and discuss its microscopic features, including the immunohistochemical characteristics, and differential diagnosis of this uncommon presentation.

Esclerose tuberosa é uma condição rara e autossômica dominante. Miofibroblastos são células que exibem fenótipo híbrido entre fibroblastos e células musculares lisas. O objetivo deste caso clínico é mostrar as características clínicas e histopatológicas da esclerose tuberosa e avaliar miofibroblastos nos angiofibromas cutâneos dessa condição. Lesões removidas foram coradas em HE e tricrômico de Masson. Para determinar a presença de miofibroblastos foi usada imunoistoquímica para α-SMA. Essa reação mostrou-se negativa para miofibroblastos. Como α-SMA é um marcador específico para essas células, esse resultado sugere que miofibroblastos não estejam envolvidos com os angiofibromas da esclerose tuberosa descrita.

Tuberous sclerosis is a rare autosomal dominant disorder. Myofibroblasts are cells with a hybrid phenotype between fibroblasts and smooth muscle cells. The objective of this study is to describe clinical and histopathological characteristics of tuberous sclerosis and to conduct an immunohistochemical evaluation of myofibroblasts in cutaneous angiofibromas present in this condition. Lesion sections removed were stained with hematoxylin-eosin and Masson's trichrome. Immunohistochemistry against α-SMA was done to determine the presence of myofibroblasts, and the reaction was negative. Since α-SMA is a specific marker for myofibroblasts, this result suggests that myofibroblasts are not involved in cutaneous angiofibromas present in the tuberous sclerosis case reported.