RESUMO
An adult male Australian parakeet (Melopsittacus undulatus) presented a firm nodular lesion in the lateral metacarpal region of the right wing. Microscopically, there were neoplastic cells, round and polyhedral in shape, with abundant, slightly eosinophilic granular cytoplasm; they were strongly periodic-acid Schiff-positive and resistant to diastase digestion. Some groups of neoplastic cells were immunopositive for smooth muscle actin and desmin. There was no immunopositivity for S-100 protein, CD68 and cytokeratin. Ultrastructurally, the neoplastic cells were round and polygonal in shape, and they were characterized by abundant cytoplasm with numerous homogeneous osmophilic bodies covered by an electron-dense membrane (lysosomes). The histopathologic, immunohistochemical and ultrastructural features of the neoplastic tissue are consistent with a granular cell tumour, which has been described in different animal species and anatomic locations; however, this seems to be an infrequent neoplasm in Australian parakeets. The immunopositivity of the neoplastic cells for smooth muscle actin and desmin, as well as slight positivity for muscle with Masson's trichrome, suggest that this is a tumour of myogenic origin.
Assuntos
Doenças das Aves/patologia , Tumor de Células Granulares/veterinária , Melopsittacus , Neoplasias Cutâneas/veterinária , Animais , Austrália , Doenças das Aves/metabolismo , Desmina/metabolismo , Diagnóstico Diferencial , Tumor de Células Granulares/metabolismo , Tumor de Células Granulares/patologia , Tumor de Células Granulares/ultraestrutura , Imuno-Histoquímica/veterinária , Lisossomos/patologia , Lisossomos/ultraestrutura , Masculino , Microscopia Eletrônica/veterinária , Pele/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/ultraestruturaRESUMO
The central granular cell odontogenic tumor (CGCOT) is a rare lesion that usually affects the posterior region of the mandible of young adults. We present a case of CGCOT involving the mandible of a 20-year-old white woman, emphasizing the immunohistochemical characteristics using a large panel of antibodies. The lesion was removed surgically, and after 4 years of follow-up, there are no evidences of recurrences. The odontogenic epithelium (OE) showed positivity for cytokeratins (CKs) AE1/AE3, 34betaE12, CK5, CK7, CK8, CK14, CK19, E-cadherin, beta-catenin, CD138, and p63. The granular cells were positive for vimentin, CD68, lysozyme, muscle-specific actin, alpha-smooth muscle actin, calponin, neuron-specific enolase (NSE), CD138, and bcl-2. Dendritic-like cells surrounding the OE displayed positivity for vimentin, CD1a, S100, CD68, and bcl-2, but it was negative for factor XIIIa, supporting a Langerhans cell phenotype. Ki-67 labeling index was 1.8%, whereas p53 was negative. These data confirm the benign nature of CGCOT, the association of OE with Langerhans cells, and a variable phenotype of the granular cells.
Assuntos
Biomarcadores Tumorais/metabolismo , Tumor de Células Granulares/metabolismo , Neoplasias Mandibulares/metabolismo , Tumores Odontogênicos/metabolismo , Intervalo Livre de Doença , Feminino , Tumor de Células Granulares/patologia , Tumor de Células Granulares/cirurgia , Humanos , Imuno-Histoquímica , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/cirurgia , Tumores Odontogênicos/patologia , Tumores Odontogênicos/cirurgia , Adulto JovemRESUMO
Only 4 cases of granular cell tumor of the thyroid have been previously reported in the English literature. We report herein the fifth case of this uncommon neoplasm and the first one affecting a male patient. The tumor was well circumscribed and located to the left thyroid lobe, near the isthmus. Histologically, the tumor was composed of large, rounded, granular eosinophilic cells that were immunohistochemically positive for S-100, calretinin, and PGP9.5 and negative for cytokeratin AE1-3, TTF-1, and thyroglobulin.
Assuntos
Tumor de Células Granulares/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Calbindina 2 , Tumor de Células Granulares/metabolismo , Tumor de Células Granulares/patologia , Humanos , Masculino , Proteína G de Ligação ao Cálcio S100/metabolismo , Proteínas S100/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Ubiquitina Tiolesterase/metabolismo , Adulto JovemRESUMO
We describe 2 cases of malignant granular cell tumor. A marked discrepancy exists concerning the criteria of malignancy of this rare entity, which was diagnosed in male patients aged 41 and 52 years, respectively. They presented with tumors measuring more then 3.5 cm; one arose in the dermis and subcutaneous tissue in the region of the scapula, whereas the other was situated in deeper soft tissue in the pelvis. One case, with previous diagnosis of benign granular cell tumor, presented local recurrence 2 years after the initial diagnosis. The other case presented a fascicular pattern of growth invading adjacent muscular tissue. Both neoplasms were composed of polygonal and spindle cells, showing abundant cytoplasm, vesicular nuclei with large nucleoli, high nuclear-to-cytoplasmic ratio, and pleomorphism. Immunohistochemically, the neoplastic cells of both cases were positive for vimentin, S100 protein, neuron-specific enolase (NSE), and CD68. In addition, high expression of p53 and MiB1 (Ki67) was detected. Herein, we discuss the morphologic and immunohistochemical criteria of malignancy of granular cell tumors. Int J Surg Pathol 9(3):255-259, 2001