Clinical, morphological and immunohistochemical characterization of a recurrent B1 type thymoma

Type B1 thymoma is widely accepted as a tumor with a non-aggressive behavior even in advanced stage. Most of these tumors are classified as Masaoka stage I or II. They rarely relapse or metastasize and the surgical treatment is considered curative. We have investigated a case of thymoma type B1, which relapsed 13 months after the primary tumor was excised. The patient was diagnosed with a local tumor recurrence after investigations due to the worsening of clinical symptoms of myasthenia gravis (MG). The therapy management of such cases is debatable and protocols not yet approved. For this reason, we have analyzed different clinical, morphological and immunohistochemical characteristics that may be considered as prognostic factors for a more aggressive behavior of such tumors. We have identified some morphologic characteristics rarely seen in this type of thymoma but none considered of prognostic value. In addition, we investigated some possible immunohistochemical markers that are generally associated with a more aggressive clinical outcome in different malignant tumors and thymic epithelial tumors. Among these markers, only p53 was positive and may be useful to predict a more aggressive evolution. In summary, probably the more appropriate approach of the patient is the clinical follow-up together with treatment of the clinical symptoms of myasthenia gravis.

Analysis of the immunohistochemical expression of mammaglobin A in primary breast carcinoma and lymph node metastasis

Mammaglobin A is a specific marker of the normal and neoplastic mammary tissue that usually is detected by RT-PCR. Few data are available about the immunohistochemical expression of this marker in mammary carcinoma and about the significance of the positive reaction. Our purpose was to investigate the sensitivity of the mammaglobin expression in breast cancer and to determine its correlations with conventional prognostic parameters. There were investigated 47 patients with breast carcinoma, and slides from paraffin blocks were stained with an antibody against mammaglobin. The immunohistochemical reaction was scored based on the percentage of positive tumor cells in both primary tumors and lymph node metastasis. Positive reaction for mammaglobin was found in the normal mammary tissue adjacent to the tumor in all cases, in 78.72% primary breast carcinoma, and in 58.06% of cases with lymph node metastases. A significant correlation was found between the mammaglobin expression in the primary tumor, grade, and lymph node status, but not with the age of the patient, pathologic subtype of carcinoma and stage of the tumor. The ductal in situ carcinoma associated to the invasive tumor did not influence significantly the prognostic value of mammaglobin expression. Out results suggest that mammaglobin is a sensitive marker of breast carcinoma, it defines a subgroup of patients with better prognosis and is a useful method to detect breast cancer metastases.

From conventional pathologic diagnosis to the molecular classification of breast carcinoma: are we ready for the change?

Breast cancer is the most frequent malignant tumor in women and the diagnosis, prognosis and therapeutic strategy are based on the pathologic report. In last years, it was shown that conventional pathologic diagnosis brings few data about prognosis and tells nothing about the response of the tumor to specific therapy. In an effort to improve the molecular characterization of breast cancer, gene profile analysis was performed in a large number of cases. Based on this analysis, there were characterized five molecularly different subclasses: basal-like, luminal type A and B, HER-2, and unclassified. It was shown that prognosis and response to adjuvant therapy is significantly different in these five subtypes. Immunohistochemistry was demonstrated to be a good and acceptable surrogate of the gene analysis. A panel of antibody that includes estrogen receptors (ER), progesterone receptors (PR), Her2 protein, cytokeratin 5 (CK5), epidermal growth factor receptor (EGFR), p53 mutation, and Bcl-2 expression, can discriminate between these five molecular subclasses. In the present review there are presented the main characteristics of the molecular subclasses, the relationships with the conventional pathologic classification, critical problems of the molecular classification and their impact on prognosis and therapy.

E-cadherin expression in invasive breast cancer

There were investigated 22 cases with invasive breast carcinoma from the archive material, and the immunohistochemical expression of E-cadherin was correlated with clinical stage, pathological type, grade of the tumor, and lymph nodes status. The expression of E-cadherin was assessed by the pattern of the final product of reaction and number of positive cells. The reaction was appreciated as normal if over 70% of tumor cells showed membrane of membrane and cytoplasmic pattern, and aberrant, if less than 70% of tumor cells were positive. There were found 45.5% cases with normal expression and 54.5% with aberrant expression. Strong positive reaction was found mainly in tumor cells invading the adipose tissue, but the reaction was weak or negative in tumor cells within the vessels. Both normal and aberrant expression of E-cadherin correlates with grade and with clinical stage. In our study was found that the increase of the tumor grade is associated with decrease in the expression of E-cadherin. Tumors over 2 cm in their larger diameter showed a decreased expression of E-cadherin. Seventeen from 22 cases with lymph node metastasis had positive reaction in the primary, but there were not found significant differences between the normal and aberrant expression.

Neural granular cell tumor. A case report

It is presented the case of an old female with a solitary tumor at the level of the thorax. The specimen was processed using the routine histological technique and slides were stained with conventional morphologic, histochemical and immunohistochemical methods. On Hematoxylin-Eosin stained slides were noticed large cells with acidophilic cytoplasm, with granular pattern. S100 protein was intensely expressed in all tumor cells and neuron specific enolase was moderate positive. CD68 positive reaction was considered the expression of lysosomes accumulation in the cytoplasm of tumor cells. Histological and immunohistochemical findings are consistent with the diagnosis of neural granular cell tumor.

Vascular endothelial growth factor A (VEGF A) as individual prognostic factor in invasive breast carcinoma

VEGF is a potent mitogen for endothelial cells and also acts in an autocrine and paracrine manner for development of tumor cells in breast cancer. Correlations between VEGF and some clinicopathologic findings were largely studied but results were controversial. Our purpose was to find if VEGF could be used as individual prognostic factor in invasive breast carcinoma. We included in our study 35 cases of invasive breast carcinoma, which were immunostained for VEGF using monoclonal antibodies anti-VEGF clone VG1. The assessment of VEGF expression used a scoring system, which included an intensity parameter correlated with percent of positive tumor cells. We found positive correlation between ductal invasive carcinoma type of breast cancer and VEGF expression. In addition, presence of inflammation associated with breast malignancies had a significant correlation with VEGF positive staining. Because of these correlations found in our study, we concluded that VEGF could not be used as individual prognostic factor in invasive breast carcinoma.

Relevance of the immunohistochemical expression of cytokeratin 8/18 for the diagnosis and classification of breast cancer

PURPOSE

The aim of our study was to characterize and describe the different immunohistochemical expression patterns of cytokeratin 8/18 (CK8/18) in breast tumors and to make a correlation between histopathology, immunohistochemistry for CK8/18 and its possible diagnostic value of this pair of keratins for molecular classification of breast cancers.

MATERIAL AND METHODS

Forty cases of breast tumors immunostained with monoclonal antibodies against CK8/18 using a polymer based detection system and diaminobenzidine as chromogen were microscopically evaluated in normal and tumor breast tissue concerning the intensity, distribution and density of positive cells. Association with histopathology and nuclear grade were also studied.

RESULTS

Three different models of positive reaction were found: (1) normal cytoplasmic with intense and diffuse pattern, (2) aberrant membrane pattern and (3) aberrant cytoplasmic granular pattern associated with membranous positive reaction. Normal expression of CK8/18 was found in 23 cases of breast cancer, aberrant membranous in nine cases and aberrant with granular pattern in four cases. Further studies will be needed to elucidate these differences and possible correlation with other molecular markers.

CD105/smooth muscle actin double immunostaining discriminate between immature and mature tumor blood vessels

The aim of the study was to demonstrate the value of the double immunostaining for endothelial and perivascular cell to discriminate mature from immature tumor-associated blood vessels in mammary carcinoma. We used the specific endothelial marker CD105 to highlight the activated endothelial cells and antibodies against smooth muscle cell actin (SMA) for perivascular cells, applying Envision Doublestain system (HRP/DAB-APAAP/Fast Red). We found an inverse correlation between the immunoexpression of CD105 and SMA in normal vessels and a strong positive signal for CD105 in the intratumor single endothelial cells and immature vessels. Only few blood vessels were positive for both CD105 and SMA within the tumor area. The signal for the endothelial marker was weak and inconstant, and significantly diminished when the SMA immunoexpression was increased for the same vessel. The differentiation between vessels with and without perivascular cells coverage using double immunostaining for CD105/SMA may be an important step in the selection of the mammary tumors, which could have a high grade of responsiveness to antiangiogenic therapy with monoclonal antibodies against CD105 antigen.

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.

Immunohistochemical localization of prostate-specific antigen in benign and malignant breast conditions

We studied 24 selected breast tumors and 3 lymph nodes metastasis from patients with breast carcinoma. The biopsies were formalin-fixed, paraffin-embedded and sections were stained with haematoxylin-eosin. Additional sections from each case were immunostained for prostate specific antigen (PSA), using the EnVision technique. PSA was detected in 7% of normal breast tissues, in 54.5% of benign tumors and 46.5% of malignant tumors. The lesions with apocrine metaplasia were intense and constantly positive, the cystic dilated ducts and the areas with mastopathy were negative. Intense staining for PSA has been found in well-differentiated tumors, while the undifferentiated tumors were usually PSA-negative. The PSA-positivity in 2 of the 3 lymph nodes metastasis indicates that PSA immunoreactivity alone is not an individual prognostic indicator, but it correlates with the hormonal status of the female body. We discuss the results in terms of clinical implications of PSA immunoreactivity detection in mammary gland and other extra-prostatic sources.

Endothelial cells from hematopoietic stem cells are functionally different from those of human umbilical vein

Hematopoietic stem cells have a remarkable plastic capacity, which allows them to differentiate into various cells, such as immune cells, nervous cells, muscle cells, bone and cartilaginous cells. The aim of this study was to show the capacity of stem cells to differentiate into endothelial cells, in culture, after addition of endothelial cells growth supplement (ECGS). We also compared the behavior of these cells with that of endothelial cells obtained from human umbilical vein (HUVEC). CD34+ cells obtained by immunomagnetic separation from human umbilical cord and placental blood were used. After 12-15 days of culture in a medium containing ECGS, the cells showed morphological changes characteristic to endothelial cells and immunocytochemical analysis revealed the presence of CD31 surface antigen and von Willebrand factor. The flow-cytometric analysis of endothelial cells adhesion molecules (ECAM) showed that endothelial cells derived from CD34+ cells expressed CD54/ICAM-1 9.65+/-0.2% and CD106/VCAM 7.73+/-0.3%, values similar to those expressed by HUVECs. After TNF incubation, ECAM expression increased only in HUVECs. These data demonstrate that a fraction of circulating CD34+ cells may develop some endothelial cell characteristics when cultured with ECGS, but they are functionally different from HUVECs.

Factors associated with atrial fibrillation in patients with mitral stenosis: a cardiac catheterization study

Atrial fibrillation (AF) is frequently found in association with rheumatic mitral valve disease. To study the interrelation of factors contributing to the risk of AF in patients with mitral stenosis, we examined a cardiac catheterization database of a series of 314 patients. Patients with AF were older, 53.4 +/- 6.1 years versus 51.7 +/- 7.2 years (p = 0.03), and had a lower cardiac index, 2.3 +/- 0.6 L/min/m2 versus 2.6 +/- 0.7 L/min/m2 (p = 0.0002), than patients in sinus rhythm at catheterization. The mitral valve area was significantly smaller in patients with AF than in patients in sinus rhythm, 1.2 +/- 0.5 cm2 versus 1.6 +/- 0.7 cm2 (odds ratio 1.40/0.25 cm2 decrease; p = 0.0001) as was mitral valve index. The pressure-AF association with the highest statistical significance was seen with mean right atrial pressure, 10.6 +/- 4.9 mm Hg versus 7.6 +/- 3.8 mm Hg (odds ratio 2.24; p < 0.0001). Other variables with significant positive associations by univariate analysis were pulmonary artery wedge pressure, pulmonary artery mean pressure, and pulmonary resistance. When stepwise logistic multiple regression analysis was performed, the results indicated that both severity of mitral stenosis and increased right atrial pressure were independently associated with AF in this population with mitral stenosis. After adjustment was performed for these variables, age was not independently associated with AF.