Metals and nanocrystalline alloy powders can be produced by high-energy milling and be consolidated by sintering techniques; the use of relatively low sintering temperatures maintains nanometric grains by avoiding grain growth. In the present study, 2024 aluminum alloy powders were produced by milling at cryogenic temperatures (cryomilling) and consolidation using spark plasma sintering (SPS). The thermal stability and microstructure of the nanometric 2024 Al alloy powder produced by cryomilling were analyzed. The milled powder was degassed to improve its sintering behavior and avoid the presence of pores in the final sintered piece. When the material was consolidated by SPS at a temperature of 525 ºC and under a pressure of 60 MPa, the resulting alloy density was 98% and an ultra-fine grained (100-300 nm)/micrometric microstructure. The hardness and microhardness of the milled degassed sintered samples showed values superior to atomized samples. The material also presented nanopores in the grain boundaries, very fine precipitates of AIN, rounded θ phases (Al2Cu), and elongated S phases (Al2CuMg).

Objective This study aimed to evaluate the results of thyroid surgeries with hospitalization periods shorter than 18 hours performed in a surgical endocrinology service, correlating these results with type of procedure, the definitive diagnosis and complications associated with the procedure.Subjects and methods The procedures performed, complications associated, hospitalization period, and relationships among these variables were assessed in consecutive patients subjected to different types of thyroid surgeries from January 1997 to March 2014 by the same group of surgeons. Data were analyzed by frequency, and the associations between the hospitalization period and other variables were analyzed using the Pearson chi-square test and Fisher’s exact test, using a multiple comparisons test with Bonferroni correction.Results Among the 3,411 surgeries performed, 799 of them were malignant neoplasia, 2,505 were benign tumors and 107 were Graves’ disease. The following procedures were performed: total thyroidectomy (1597 patients); total thyroidectomy with neck exploration (369 patients); lobectomy plus isthmectomy (1084 patients); total thyroidectomy complementation (145 patients); total thyroidectomy with neck dissection (84 patients); modified radical total thyroidectomy (13 patients); nodulectomy (11 patients); unresectable (9 patients); central neck dissection (48 patients); lateral neck dissection (38 patients); and others (13 patients). The following surgical complications, characteristic of the procedure: hemorrhage in 41 (1.2%) patients, hypoparathyroidism in 10 (0.3%) patients and recurrent laryngeal nerve (RLN) injury in 23 (0.7%) patients. Hospitalization shorter than 18 hours was observed in 97% of patients.Conclusion Thyroid surgery can be safely performed in virtually all patients on an overnight basis in specialized services.

Tumores mesenquimais da glândula tireoide são extremamente raros. Os autores relatam um caso de osteossarcoma primário de tireoide em um paciente masculino que apresentou massa tumoral na região cervical. A tomografia computadorizada demonstrou um grande tumor no lobo tireoideano direito, com zonas de calcificação. A peça cirúrgica consistia de um tumor marrom-acinzentado e firme, medindo 13 × 11 × 7,5 cm. À microscopia, foi encontrada neoplasia maligna de alto grau composta por células poligonais de tamanho intermédio, com um padrão condroide em algumas áreas e formação de osteoide. O processo revelou imunoexpressão negativa para AE1/AE3, proteína glial fibrilar ácida (GFAP), antígeno da membrana epitelial (EMA), p53 e fator de transcrição da tireoide (TTF-1) e imunopositividade para CD99 e S100. O diagnóstico de osteossarcoma primário da glândula tireoide foi, então, estabelecido.

Primary mesenchymal tumors of the thyroid gland are extremely rare. The authors report a case of primary thyroid osteosarcoma in a male patient presenting a tumoral mass in the neck. CT scan demonstrated a large tumor in the right thyroid lobe with areas of calcification. The surgical specimen consisted of a hard brown-gray tumor, measuring 13 × 11 × 7.5 cm. Microscopy revealed a high-grade malignant neoplasm composed of polygonal cells of intermediate size, chondroid pattern in some areas and osteoid formation. The process was immunonegative for AE1/AE3, glial fibrillary acidic protein (GFAP), epithelial membrane antigen (EMA), p53 and thyroid transcription factor-1 (TTF-1), and immunopositive for CD99 and S100. Thus the diagnosis of primary osteosarcoma of the thyroid gland was established.

O plasmocitoma extramedular constitui 3%-5% de todas as neoplasias de plasmócitos e aproximadamente 80% dos casos ocorrem no trato respiratório superior. Plasmocitomas primários da tireoide (TPP) são tumores raros. Os autores relatam um caso de TPP em um paciente masculino referindo dispneia e disfagia. O exame físico e a tomografia computadorizada revelaram tumor sólido comprometendo a glândula tireoide, medindo 12 cm na maior dimensão, o qual foi submetido à biópsia cirúrgica. À microscopia, foi identificada neoplasia maligna hipercelular constituída por células redondas/plasmocitoides dispostas em ninhos sólidos, as quais exibiam imunoexpressão positiva para CD138, antígeno da membrana epitelial (AME), cadeias leves kappa e oncogene mieloma múltiplo 1 (MUM1). O diagnóstico de TPP foi, então, estabelecido.

Extramedullary plasmacytoma comprises 3%-5% of all plasma cell neoplasms, and approximately 80% of the cases occur in the upper respiratory tract. Primary thyroid plasmacytomas (PTP) are rare tumors. The authors report a case of PTP in a male patient with dyspnea and dysphagia. Physical examination and computerized tomography (CT) scan revealed a solid tumor affecting the thyroid gland, measuring 12 cm in its greatest dimension. Surgical biopsy was performed. Microscopy revealed a hypercellular malignant neoplasm composed of round plasmacytoid cells arranged in solid nests, which showed a positive immunoexpression for CD138, epithelial membrane antigen (AME), kappa light chains and multiple myeloma oncogene 1 (MUM1). The diagnosis of PTP was accordingly established.