We present the case of rare mediastinum epithelioid hemangioendothelioma with peculiar histological features such as prominent spindling of neoplastic cells and abundant metaplastic bone formation in aggregate with aggressive clinical behavior that exhibited a profound metastatic poteintial. Objective: Thymic carcinomas comprise rare malignant epithelial neoplasms, which exhibit a disproportionately large variety of growth patterns. We present three cases of primary thymic carcinomas, including two squamous cell carcinomas and one papillary adenocarcinoma. Method: All three patients were males, aged 51, 61 and 77 years, and presented with mediastinal masses measuring 17 cm, 6.5 cm, 3.7 cm in maximal diameter respectively. Results: Microscopically the first two tumors were poorly differentiated squamous cell carcinomas, immunohistochemically positive for CD5 and CD117, whereas the third tumor was a papillary adenocarcinoma, positive for CD5 and negative for CD117 and TTF-1. Immunohistochemical features of the tumors were supportive of thymic derivation. Conclusion: Primary thymic carcinomas are rare malignant tumors with clear-cut atypia, largely lack of organotypic features and a very diverse differentiation. Squamous cell carcinoma is the most frequent subtype. They are often a diagnosis of exclusion, since metastases to thymus and anterior mediastinum, mainly from the lung, are far more common. Immunoreactivity to CD5, CD70 and CD117 may support the thymic origin of neoplastic squamous cells. Treatment options include surgical excision, radiation and/ or chemotherapy depending on tumor stage and patient's condition. The prognosis is generally poor with squamous cell carcinomas having a slightly more favorable outcome. Wednesday, 12 September 2012, 09.30 -10.30 Objective: Surgical blood loss can lead to ineffective tissue perfusion of vital organs. Physiologic solution chosen for blood volume replacement may be determinant for preserving renal integrity. Our aim is to study kidney histopathological changes in a hemorrhagic model, followed by intravascular volume replacement with Ringer's lactate or Hydroxyethylstarch (HES) 130/0.4 solutions. Method: Thirty one pigs under general anaesthesia with propofol and remifentanil underwent haemorrhage at a volume of 30 ml kg-1, over 20 min. After a waiting period of 20 min, intravascular volume was replaced using HES 130/ 0.4 (G1) and Ringer's lactate (G2). One hour after, pigs were euthanized with IV potassium chloride and sixty two renal samples were taken for histopathological examination, using PAS staining. Renal damage was assessed for glomerular, tubulointerstitial and vascular lesions. Results: Mean arterial pressure reached 40 mmHg after bleeding, and recovered for values above 60 mmHg in both groups after volume replacement. Histopathological lesions observed in G2 were more frequent than those in G1. Conclusion: HES 130/0.4 may reduce the incidence of histopathological lesions secondary to renal hypoperfusion after severe bleeding when compared with Ringer Lactate.