The interior structure of breast microcalcifications assessed with micro computed tomography.

BACKGROUND: Morphology microcalcification descriptors help stratify the risk of breast malignancy. Micro CT is feasible for visualization of the fine-structure of tissues and may be suitible for high resolution microcalcification analysis. PURPOSE: To analyze the interior structure of microcalcifications using a micro CT imaging system. MATERIAL AND METHODS: Core needle breast biopsy specimens from 16 women with clustered microcalcifications were examined with micro CT. The samples measured between 0.8 to 1.2 mm in diameter. Micro CT scans with an isotropic voxel size of 8.4 µm were obtained to generate two- and three-dimensional images of the microcalcifications. The number of microcalcifications were counted on the magnified specimen radiogram and on micro CT. Attenuation values of microcalcifications were measured by drawing a region of interest (ROI) in the center of the microcalcifications. Two blinded observers assessed the morphology and the interior structure of microcalcifications. RESULTS: Five patients had benign and 11 patients had malignant breast lesions. On micro CT, microcalcifications of benign tissue showed a coarse lamellar or trabecular interior structure, whereas microcalcifications of breast cancer tissue showed a more uniform granular interior structure. There was no correlation between attenuation values of benign compared with malignant microcalcifications. CONCLUSION: On micro CT, an interior structure of microcalcifications is detectable. Benign and malignant microcalcifications display different patterns of interior structure.

Fine structure of breast tissue on micro computed tomography a feasibility study.

RATIONALE AND OBJECTIVES: To evaluate the feasibility of micro computed tomography (CT) to assess the fine structure of breast tissue. METHODS AND MATERIALS: Breast core needle biopsy specimens (0.8 to 1.2 mm diameter) from fifteen women with clustered microcalcifications were examined using micro CT with isotropic voxels of 8.4 µm. Reconstructed two- and three-dimensional images were compared with the corresponding histological slices. Gray-scale measurements were performed in adipose tissue, fibroglandular tissue, fibrous tissue, microcalcifications, and tumor. The Tukey-Kramer method was applied to test the statistically significant differences between gray-scale attenuation values of breast tissue components. RESULTS: Soft-tissue architecture appearance at micro CT closely approximated that obtained by light microscopy at low power field. The Tukey-Kramer method revealed statistically significant differences for attenuation values for all combinations of breast tissue components with the exception of fibroglandular tissue versus fibrous tissue. CONCLUSIONS: Micro CT is feasible for the differentiation of breast tissue components from core needle specimens.

Where does the antigen of cutaneous sarcoidosis come from?

BACKGROUND: The antigen pathway of cutaneous sarcoidosis remains obscure. We have investigated topographic involvement of inflammatory cells and lymphatic vessels. METHODS: Eleven cutaneous biopsies from eight patients were studied, along with controls from other granulomatous disorders and various skin lesions. Markers for lymphocytes, dendritic cells (DCs), and lymphatic vessel endothelial cells were detected using immunohistochemistry. RESULTS: S100(+) and CD1a(+) immature DCs (Langerhans cells) occurred more frequently within the epidermis, whereas S100(+), fascin(+), or CD83(+) maturing DCs occurred more frequently beneath the epithelium in cutaneous sarcoidosis cases than in controls (e.g. CD83, cutaneous sarcoidosis vs. other granulomatous disorders: r = 0.557, p = 0.011). Fascin(+) and CD83(+) mature DCs were often closely attached to CD3(+) T-lymphocytes around dermal granulomas. D2-40(+) lymphatic vessels were often found surrounding dermal granulomas, especially those located in the deeper dermis, in contrast to fascin(+) blood vessels. CONCLUSIONS: Antigen-capturing by immature DCs seems to take place initially in the epidermis, followed by maturation of DCs. These mature DCs may present the processed antigen to T-lymphocytes that cause dermal granulomas either in the interstitium of the upper dermis, or in or around lymphatic vessels of the lower dermis. Environmental antigen could be verified by skin test.

Genome-wide expression profiling reveals new insights into pathogenesis and progression of testicular germ cell tumors.

Testicular germ cell tumors (GCT) are the most frequent malignancy in young adults and arise from intratubular germ cell neoplasia undetermined (IGCNU, also referred to as carcinoma in situ, CIS). To determine the transcriptional programs involved in the transition from normal germ cells to GCT, and to further elucidate genetic differences between seminomas and non-seminomatous GCT the global expression profile of 12 neoplastic and 3 normal testicular tissues were investigated by whole genome cDNA microarrays. Transcriptional differences between seminomas and embryonal carcinomas were determined and gene signatures characterizing histological subtypes of GCT were identified. The most significant difference between seminomas and embryonal carcinomas was the expression of spermatogenesis-associated genes (PRAME, MAGEA4, SPAG1, HPX) in seminomas and regulatory genes DNMT3B and SOX2 as well as small molecular weight keratins KRT8, KRT18 in embryonal carcinomas. The expression of several selected genes (CK18, MAGE-A4, SOX2, DNMT3B, CD30, KIT) was studied by immunohistochemistry or reverse transcriptase-polymerase chain reaction (RT-PCR) in a large collective of GCT. In summary, our data identified tumor type-specific gene signatures of GCT and provided new insights into genetic pathways driving the transition to seminomas and embryonal carcinomas from their respective precursor lesions.

Gene expression profiling identifies new biological markers of neoplastic germ cells.

BACKGROUND: There is only limited knowledge about gene expression in human testicular germ cell tumors of adolescents and adults (TGCTs), and, in particular in its preinvasive stage intratubular germ cell neoplasia unclassified (IGCNU). MATERIALS AND METHODS: Global gene expression was studied in 10 invasive human testicular germ cell tumors (TGCTs), 7 intratubular germ cell neoplasia unclassified (IGCNU) and 3 normal testes. The pattern of expression of several genes was studied by immunohistochemistry on tissue microarrays containing 126 TGCTs, IGCNU, normal testes and in 5 fetal testes. RESULTS: RAS-related genes (KRAS2, RALA, RAB39B) and various core markers of embryonic stem cells were overexpressed in IGCNU compared to normal testes. CD9, PODXL and centromere-specific histone-H3-like protein CENPA were specifically identified in IGCNU, seminomas, embryonal carcinomas and in fetal gonocytes. Embryonic stem cell regulator SOX2 and downstream targets of the Nodal pathway were up-regulated in embryonal carcinoma only but not in IGCNU/seminoma. Preliminary data revealed that the expression profile of IGCNU is dependent on the histology of the adjacent invasive tumor. CONCLUSION: Our study determined the genes involved in early pathogenetic events of neoplastic germ cell formation, provided new insights into genetic pathways driving the transition of embryonal carcinoma and seminoma from IGCNU and identified new biomarkers of neoplastic germ cells such as CD9, CENPA and PODXL.

The expression of the carboxyl ester lipase gene in pancreas and pancreatic adenocarcinomas.

Since pancreatic cancer is an aggressive and often incurable malignancy, we investigated if the carboxyl ester lipase gene (CEL) is specifically expressed in pancreatic tissues and its promoter can be used for a specific suicide gene approach. Twenty-five tumor samples, 24 samples of normal pancreatic tissue and control tissues from other organs were examined by radioactive in situ hybridization (ISH) to localize CEL mRNA. Two carcinoma samples and 6 permanent cell lines were examined by reverse transcriptase-polymerase chain reaction (RT-PCR). By ISH, we verified a strong CEL gene expression in acinar cells of the normal pancreas. A minor expression was noted in a single sample of acinar cell carcinoma and adenocarcinomas did not show any expression. By RT-PCR, no specific expression in both tested adenocarcinomas was observed. In summary, these results show that, contrary to notable expression of carboxyl ester lipase in acinar cells of normal pancreatic tissue, this lipase is not significantly active in pancreatic adenocarcinomas and thus not an apt genetic marker for diagnostic or therapeutic approaches.

Three-dimensional imaging and morphometric analysis of alveolar tissue from microfocal X-ray-computed tomography.

We evaluated microfocal X-ray-computed tomography (micro-CT) as a method to visualize lung architecture two and three dimensionally and to obtain morphometric data. Inflated porcine lungs were fixed by formaldehyde ventilation. Tissue samples (8-mm diameter, 10-mm height) were stained with osmium tetroxide, and 400 projection images (1,024 x 1,024 pixel) were obtained. Continuous isometric micro-CT scans (voxel size 9 microm) were acquired to reconstruct two- and three-dimensional images. Tissue samples were sectioned (8-microm thickness) for histological analysis. Alveolar surface density and mean linear intercept were assessed by stereology-based morphometry in micro-CT scans and corresponding histological sections. Furthermore, stereology-based morphometry was compared with morphometric semi-automated micro-CT analysis within the same micro-CT scan. Agreement of methods was assessed by regression and Bland-Altman analysis. Comparing histology with micro-CT, alveolar surface densities (35.4 +/- 2.4 vs. 33.4 +/- 1.9/mm, P < 0.05) showed a correlation (r = 0.72; P = 0.018) with an agreement of 2 +/- 1.6/mm; the mean linear intercept (135.7 +/- 14.5 vs. 135.8 +/- 15 microm) correlated well (r = 0.97; P < 0.0001) with an agreement of -0.1 +/- 3.4 microm. Semi-automated micro-CT analysis resulted in smaller alveolar surface densities (33.4 +/- 1.9 vs. 30.5 +/- 1/mm; P < 0.01) with a correlation (r = 0.70; P = 0.023) and agreement of 2.9 +/- 1.4/mm. Non-destructive micro-CT scanning offers the advantage to visualize the spatial tissue architecture of small lung samples two and three dimensionally.

Inflammatory cells in the formation of tumor-related sarcoid reactions.

Tumor-related sarcoid reactions were analyzed in 14 lymph nodes in comparison with sarcoidosis using immunohistochemical markers to lymphocytes (CD3, CD4, CD8, and CD20), myeloid-related protein (MRP) 8 and MRP14 (S100A8 and S100A9), angiotensin I-converting enzyme (CD143), and mature or immature dendritic cells (S100, HLA-DR, fascin, CD83, and CD1a). We found that solitary epithelioid cell granuloma (ECG) first occur between lymph sinus and T-zone and that multiple ECGs mainly occur within T-zone, whereas confluent types often occupy the whole lymph node except some residual lymphoid follicles. This pattern suggests a continuous spread and growth of ECGs in sarcoid reactions along T-zone, where antigen presentation mainly takes place. Irrespective of granuloma type, a constant invasion of freshly recruited MRP8 + and MRP14 + macrophages was observed. Similar to sarcoidosis, angiotensin I-converting enzyme expression was a constant finding in epithelioid and giant cells, suggesting a common inflammatory pathway. An increasing ratio of CD4 + to CD8 + T lymphocytes (r = 0.789, P = .001) and a decreasing number of S100 + and CD83 + dendritic cells (r = 0.787, P = .001) within ECGs correlated with granuloma growth, whereas CD1a + immature dendritic cells were never observed inside ECGs. Our findings show that sarcoid reactions represent a T-cell-mediated immune response, leading to histological appearance and cell distribution similar to sarcoidosis and other granulomatous conditions, but the mechanism is different from dendritic cell-based tumor vaccination. Furthermore, mature dendritic cells occur inside ECGs especially of early sarcoid reactions but may not be required for the enlargement and further maintenance of ECGs, in contrast to CD4 + lymphocytes.

Cajal-like cells in the upper urinary tract: comparative study in various species.

The interstitial cells of Cajal (ICC) play an important role in the control of gut motility. The recognition that the ICC cell membrane harbors the c-kit receptor (CD117) sparked rapid advancement in ICC research on the gut and certain pathologies using immunochemical and molecular methods. The question arises whether ICC exist in the upper urinary tract (UUT) and trigger motility. The present study analyzed the distribution of the c-kit receptor in the normal human UUT compared with various species. Immunohistochemistry (alkaline-phosphatase-anti-alkaline-phosphatase technique, immunofluorescence) was applied on serial sections using monoclonal and polyclonal antibodies recognizing the c-kit receptor. C-kit staining was compared with standard endothelial, epithelial, neurogenic, histiocytic, mast cell, and smooth muscle markers, as well as a negative control. Normal proximal, middle, and distal ureter segments were analyzed in rodents, carnivores, porcines, cow, and humans. In all species the c-kit receptor was detected in either round or spindle-shaped cells. Because of their antigenic profile, the round cells were identified as mast cells occurring in all layers of the ureteral wall except the urothelium and were more frequent in humans. In contrast, the population of spindle-shaped cells was marked only by anti-c-kit receptor antibodies, thus resembling ICC. These ICC-like cells were found among the inner and outer smooth muscle layers and in the lamina propria of all species. In humans, spindle-shaped cells were also found vertically oriented within the urothelium. Our morphological data present for the first time the distribution of ICC in the UUT of various species. The ubiquitous distribution in the entire pyeloureteral complex provides strong evidence that ICC generate electrical pacemaker activity within the UUT as an intrinsic system. Animal studies may help to understand the physiological importance of these ICC-like cells. The significance of these findings needs to be evaluated by functional studies and investigations of certain congenital pathologies with disturbance of the urinary outflow.

Cajal-like cells in the human upper urinary tract.

PURPOSE: Interstitial cells of Cajal (ICCs) have an important role in the regulation of gut motility as they are responsible for the slow wave activity of smooth muscle. It is still unknown if ICCs also occur in the human upper urinary tract. Since these cells express and are marked by the c-kit receptor CD117, we investigated its occurrence and distribution along the human upper urinary tract. MATERIALS AND METHODS: Tissues from 56 human ureters, spanning proximal, middle and distal ureter segments, were analyzed by indirect immunohistochemistry using the alkaline phosphatase-anti-alkaline phosphatase method and double labeling immunofluorescence on consecutive tissue sections. Several monoclonal and polyclonal antibodies to c-kit receptor were used in combination with various cell markers for histiocytic, mast cell, endothelial, epithelial, neuronal, smooth muscle and stem cell differentiation. RESULTS: The c-kit receptor was found in 3 cell types of the ureter and in round or spindle-shaped cells. Due to their antigenic profile the first one was revealed as mast cells occurring in all layers of the ureteral wall except the urothelium. In contrast, the population of spindle-shaped cells was only marked by c-kit receptor, thus, resembling ICCs. These ICC-like cells were found among the inner and outer smooth muscle layers, and in the lamina propria. They showed a slight decrease from proximal to distal ureteral segments. However, unlike intestinal ICCs their cytomorphology differed and some cells, representing the third group of c-kit receptor positive cells, were found within the urothelium. CONCLUSIONS: Our data demonstrate the presence of ICC-like cells and their ubiquitous distribution in the human ureter. The physiological importance and pathological significance of these findings must be evaluated by functional studies and investigations of certain pathological with urinary outflow disturbance conditions.

Different immunophenotypes in Buerger's disease.

Recently, we reviewed the morphology of 31 specimens of thromboangiitis obliterans (TAO, Buerger's disease) in a multivariate analysis and showed that certain novel features of the affected vessels are different from arteriosclerosis obliterans (ASO) and thromboembolism. However, the pathogenic concept of TAO is still controversial. We applied immunohistochemistry to 58 amputated lower extremities and five autopsy controls. At specific sites of the diseased vessels, different cellular components were immunotyped by CD3, CD4, CD20, CD31, CD68, actin and desmin. These results were carefully compared among different diagnostic groups of vasoocclusive lesions by statistical methods. Some unique characteristics of TAO were identified when compared with ASO or thromboembolism. Consistent with a primary inflammatory and immunogenic lesion, lymphocytes and especially CD4+ T cells emerged significantly in TAO vessels and their adventitia. In the subset of definite TAO cases defined by all clinical criteria, the linear arrangement of macrophages, and B- and T-lymphocytes along vascular elastic fibers was the most striking additional finding, suggesting elastic fibers are an important immunogen. However, this feature was not apparent in closely related cases, otherwise similar to TAO and different from ASO and thromboembolism. Thus, our results indicate a heterogeneous group of TAO diseases, suggesting that damage to elastic fibers may be a secondary change to primary inflammation.