RESUMO
Myopericytoma is a rare mesenchymal tumor characterized by a hemangiopericytoma-like vascular pattern with perivascular myoid differentiation. To date, only 11 cases of oral myopericytoma have been reported. To the best of our knowledge, myopericytoma with gingival involvement and associated with calcifications has not been reported, expanding their clinicopathological spectrum. Herein, we report a 12-year-old girl female patient who presented a gingival nodule diagnosed as ossifying myopericytoma, which should be considered in the differential diagnosis when assessing oral soft tissue lesions, especially in pediatric patients.
Assuntos
Imuno-Histoquímica/métodos , Miopericitoma/terapia , Criança , Feminino , Humanos , Miopericitoma/imunologiaRESUMO
The entity "pericytoma with t(7;12)" was described as a rare, distinct perivascular myoid neoplasm provisionally classified within the family of myopericytic tumors that demonstrates t(7;12)(p22;q13) translocation with resultant ACTB-GLI1 fusion and biologically was felt to behave in an indolent fashion. However, a recent study showed that tumors with this and similar translocations may have variable morphology and immunohistochemical phenotype with inconsistent myopericytic characteristics and a propensity for metastasis, raising questions regarding the most appropriate classification of these neoplasms. Herein, we report 3 additional patients with tumors harboring t(7;12) and ACTB-GLI1 fusion. The tumors arose in adults and involved the proximal tibia and adjacent soft tissues, scapula and adjacent soft tissues, and ovary. All tumors were composed of round-to-ovoid cells with a richly vascularized stroma with many small, delicate, branching blood vessels, where the neoplastic cells were frequently arranged in a perivascular distribution. Both tumors involving bone showed histologic features of malignancy. By immunohistochemistry, all tested tumors were at least focally positive for smooth muscle actin (3/3) and CD99 (patchy) (2/2), with variable staining for muscle-specific actin (2/3), S100 protein (1/3), epithelial membrane antigen (2/3), and pan-keratin (1/3); all were negative for desmin and WT1 (0/3). The 2 patients with bone tumors developed metastases (27 and 84 mo after diagnosis). Whether these tumors are best classified as malignant myopericytoma variants or an emerging translocation-associated sarcoma of uncertain differentiation remains to be fully clarified; however, our study further documents the potential for these tumors to behave in an aggressive fashion, sometimes over a prolonged clinical course.
Assuntos
Actinas/genética , Biomarcadores Tumorais/genética , Neoplasias Ósseas/genética , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 7 , Fusão Gênica , Miopericitoma/genética , Neoplasias Ovarianas/genética , Sarcoma/genética , Translocação Genética , Proteína GLI1 em Dedos de Zinco/genética , Adulto , Neoplasias Ósseas/classificação , Neoplasias Ósseas/patologia , Neoplasias Ósseas/terapia , Diferenciação Celular , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Miopericitoma/classificação , Miopericitoma/secundário , Miopericitoma/terapia , Neoplasias Ovarianas/classificação , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Fenótipo , Sarcoma/classificação , Sarcoma/secundário , Sarcoma/terapia , Resultado do TratamentoRESUMO
OBJECTIVE: The aim of this study was to analyze myopericytoma in the oral and maxillofacial region in terms of clinical appearance, diagnosis, treatment, and outcomes. STUDY DESIGN: Data on 5 new patients with myopericytoma in the oral and maxillofacial region treated at our department were collected and analyzed. RESULTS: There were 2 males and 3 females (age range 10-62 years; mean age 43.8 years). All of the 5 patients presented with masses showing benign biologic behavior. Imaging examinations with use of computed tomography or magnetic resonance imaging showed heterogeneous regions with internal contrast-enhancement or cystic change in 3 cases. All of the patients underwent surgery. Histologic examination showed a broad morphologic spectrum characterized by concentric and perivascular growth of ovoid, plump spindled, and/or round myoid tumor cells. Immunohistochemical examination showed positive staining for vimentin and smooth muscle actin, and negative for CD34 and desmin. During the follow-up period (8-56 months), there was no tumor recurrence. CONCLUSIONS: Myopericytoma in the oral and maxillofacial region always exhibits benign biologic behavior and a heterogeneous region with internal contrast-enhancement or cystic change on imaging examinations. Surgery is the first choice of treatment and results in good clinical outcomes.
