Stanford type A aortic dissection in a hypertensive patient with atherosclerosis of aorta and aortitis.

Dissection of aorta is a serious condition; the main factors are hypertension and diseases of the connective tissue or of collagen. Aortitis syndrome in combination with hypertension and atherosclerosis in association with ascending aortic dissection is rarely seen. We present the case of a 53-year-old hypertensive patient whose ascending aortic dissection was associated with pericardial effusion without rupture of the aorta and with pleural effusion. Several unusual aspects of transesophageal echocardiography are described. The intraoperative biopsy revealed inflammatory aortitis with mural hematoma, without giant cells. The literature concerning aortic dissection and aortitis is reviewed.

Thymus and thymoma: what's new?

The thymus is the prototype of lymphoid and epithelial organ that consists of lymphoid and epithelial cells. In spite of remarkable progresses made in the field of the immunohistochemical characterisation of the thymus parenchyma, the diagnosis of thymoma largely depends on the interpretation of conventional morphologic aspects. Histogenesis of this organ is a multi-step process, and many stages reproduce lesions and changes found in the adult thymus. The normal structure and its variants are extremely helpful to differentiate normal from pathologic aspects. Particular aspects of the thymus structures were shown in myasthenia gravis, despite the behaviour of thymoma in these patients is not clearly understood. Authors performed a detailed description of the conventional pathology of the thymoma, based on the new classifications, recently adopted. The immunohistochemical profile could be helpful in the diagnosis of many cases, and also seems to be useful in prediction of invasion that is the most important criterion in prognosis.

Overexpression of cytokeratin 34beta E12 in thymoma: could it be a poor prognosis factor?

We included in our study nine normal human thymuses and sixteen thymomas (1 type A, 2 type AB, 3 type B1, 3 type B2, 5 type B3 and 2 type C). The 25 patients were between 7 days and 75 years old, and were submitted to open surgery for correction of congenital heart defects or for mediastinal tumor mass. Biopsies were formalin fixed for 24 hours and then embedded in paraffin using routine procedure. Five micrometers step sections were mounted on silanized slides. Slides from each case were stained with haematoxylin and eosin method for morphological diagnosis. Additional sections were immunostained using monoclonal antibodies against high molecular weight cytokeratin clone 34beta E12. We found a very strong positive reaction for this type of cytokeratin in thymomas type B2, B3 and inconstant in type C comparative with normal thymus. Also, the number and distribution of positive epithelial cells in normal thymus versus thymomas were different. We found positive cells into capsular vessels of thymomas. This could be an invasion marker for apparent encapsulated thymomas. Strong positive reaction in almost all epithelial cells of thymomas types mentioned above was correlated in part with invasion. We concluded that expression of 34beta E12 cytokeratin is a useful marker for thymomas with high grade of malignacy, correlated with vascular and capsular invasion.