Chordomas of the mediastinum: Clinicopathologic, immunohistochemical, and ultrastructural study of six cases presenting as posterior mediastinal masses

Six cases of chordomas presenting as primary posterior mediastinal tumors are described. Three patients were female, and three were male between the ages of 8 and 65 years (mean, 40.6 years). In all cases, the tumors presented radiographically as relatively wellcircumscribed, encapsulated soft tissue masses that did not seem to be related to the thoracic or dorsal spine. Only in one case, focal infiltration of bone at the level of T6-T7 was observed at the time of surgery. Histologically, the lesions showed a spectrum of features that ranged from sheets and cords of large cells with abundant vacuolated cytoplasm to small, stellate cells embedded within an abundant mucoid matrix. In one case, the cell population showed more pronounced nuclear atypia with loss of cytoplasmic vacuolization, frequent mitotic figures, necrosis, and solid areas characterized by a perivascular distribution of atypical spindle cells set against a myxoid stroma. Another case showed features of chondroid chordoma, with an immature chondroid-appearing matrix surrounding the atypical tumor cells. Immunohistochemical studies in all cases showed positive staining of the tumor cells with CAM 5.2 and broad-spectrum keratin, epithelial membrane antigen (EMA) and vimentin, and, to a lesser extent, with S-100 protein. Stains for muscle actin, carcinoembryonic antigen (CEA), and desmin were negative. Ultrastructural examination in two cases showed a spectrum of features that varied from large cells with abundant cytoplasm containing scattered ribosomes, glycogen granules, Golgi apparatti, abundant intermediate filaments, and small lumen formation with immature microvilli to smaller cells with elongated cytoplasmic processes, fewer intermediate filaments, rare desmosome type intercellular junctions, and complexes of mitochondria/rough endoplasmic reticulum. On clinical follow-up, two patients died with metastases to the lungs, chest wall, and liver from 1 to 3 years after diagnosis, and two patients are alive and well without evidence of disease after 3 and 16 years. Chordoma should be entertained in the differential diagnosis of posterior mediastinal tumors. Application of immunohistochemical stains or electron microscopy will be of aid in separating them from other conditions that may histologically closely resemble these lesions.     

Primary malignant lymphoma of the intestine: Clinicopathologic and immunohistochemical studies of 39 cases

Clinicopathologic and immunohistochemical features in 39 cases of primary intestinal non-Hodgkin's lymphoma (NHL) in Japanese patients were studied. Only resection materials in stage I_E and II_E-1 were included in this study because of the certainty that the intestine was the primary site of the lymphoma. The updated Kiel classification was used to classify NHL Histologically, only two cases (5.1%) were follicular lymphomas, and the others were diffuse lymphomas. Twenty-eight patients (71.8%) had high-grade NHL and 11 (28.2%) had low-grade NHL. Twenty (71.4%) of the 28 high-grade NHL were centroblastic lymphomas, and 14 (70.0%) of these 20 cases of centroblastic lymphoma were the polymorphic variant. Ten (90.9%) of the 11 low-grade NHL were low-grade mucosa-associated lymphoid tissue (MALT) lymphomas. Macroscopically, 18 patients had polypoid masses, 17 ulcerative tumors and four had diffusely infiltrating NHL. Seven of the 10 low-grade MALT lymphomas were polypoid masses. Immunohistochemically, 35 lesions (89.7%) were of the B cell phenotype and three (7.7%) were of the T cell phenotype. In the remaining case, the cell lineage could not be determined. No lesions were considered to be Of histio-cytic origin. The 5 year survival rate for high-grade B cell lymphomas was poorer than for low-grade B cell lymphomas, and the present study indicated that the histological grade of the intestinal B cell lymphomas was a prognostically significant factor.     

Mucinous adenocarcinoma of the prostate: histochemical and immunohistochemical studies.

Twelve patients with primary mucinous adenocarcinoma of the prostate were included in a clinicopathologic study; criteria included a total tumor volume more than 25% mucinous and single or clustered tumor cells floating in mucin lakes. Patient ages were 57 to 81 years; tumor stages were C (three), D (five), and unknown (four). Bone was the most frequent metastatic site (usually osteoblastic), followed by lymph nodes and lungs. Serum levels of prostatic acid phosphatase and prostate-specific antigen were frequently elevated (five of 10 and three of three measured, respectively). All mucinous adenocarcinomas also contained other histologic patterns: microglandular (four), cribriform (three), comedo (two), solid (two), and hypernephroid (one). Mucinous components composed less than 50% of three tumors, 50% and 75% of six, and more than 75% of three. No tumor contained signet-ring cells. Immunoperoxidase staining was positive for prostatic acid phosphatase and prostate-specific antigen and negative for carcinoembryonic antigen. Treatment was radiation, estrogen, orchiectomy, or a combination. In two of four patients, serum prostatic acid phosphatase levels normalized after therapy. Seven patients died of disease (mean follow-up, 56 months), and five patients are alive with disease (mean, 32.2 months). The proportion of mucinous component did not affect prognosis.     

Granulated lymphocytes in human endometrium: histochemical and immunohistochemical studies.

Granulated lymphocytes with an unusual antigenic phenotype (CD56+ CD38+ CD2 +/- CD3- CD16-) form a substantial proportion of leukocytes in human endometrial stroma. The purpose of this study was to examine morphological and antigenic heterogeneity in endometrial granulated lymphocytes (eGL) in imprint preparations, paraffin-embedded sections and frozen sections. eGL in decidual imprints showed variations in cell size, nuclear size, shape and chromatin content and the number and size of cytoplasmic granules. eGL were detected in paraffin-embedded sections using phloxine tartrazine, alcian blue and toluidine blue stains. There was no difference in the number of eGL among the three stains but the granules appeared smaller and more regular when stained with toluidine blue. The proportion of stromal cells which were leukocytes increased from 8.2% in proliferative endometrium to 31.7% in early pregnancy decidua. The number of CD56+ and CD38+ cells increased in late secretory endometrium; CD56+ cells formed greater than 75% of the leukocytes in first trimester decidua. The increased number of CD2+ cells in decidua was not comparable with CD56+ and CD38+ cells suggesting that a lower proportion of CD56+ cells in first trimester decidua coexpress CD2, an observation which was supported by double labelling studies. eGL therefore show morphological and antigenic heterogeneity and the study of granulated lymphocytes in pathological endometrium and decidua will require careful phenotypic and morphological analysis of accurately dated samples.     

Rhinovirus and the lower respiratory tract

Human rhinoviruses (HRVs) are well-recognised causes of common colds and associated upper respiratory tract complications such as sinusitis and otitis media. This article reviews information linking HRV infection to illness in the lower respiratory tract. HRVs are capable of efficient replication in vitro at temperatures present in the tracheobronchial tree and have been shown to cause productive infection, elaboration of cytokines and chemokines, and up-regulation of cell surface markers in human bronchial epithelial cells. In situ hybridisation studies have proven that HRV infection occurs in the tracheobronchial tree following experimental infection. Clinical studies report that HRV infection is the second most frequently recognised agent associated with pneumonia and bronchiolitis in infants and young children and commonly causes exacerbations of pre-existing airways disease in those with asthma, chronic obstructive pulmonary disease or cystic fibrosis. HRV infection is associated with one-third to one-half of asthma exacerbations depending on age and is linked to asthma hospitalisations in both adults and children. Limited information implicates HRV infection as a cause of severe lower respiratory tract illness in older adults and in highly immunocompromised hosts, particularly bone marrow transplant recipients. More information is needed about the pathogenesis of HRV infection with regard to lower respiratory tract complications in these diverse patient groups. Given the large unmet medical need associated with HRV infections, safe and effective antiviral agents are needed for both prevention and treatment of these infections.     

Amyloidosis localized to the lower respiratory tract: probable immunoamyloid nature of the tracheobronchial and nodular pulmonary forms

Seven patients with localized nodular pulmonary amyloidosis and four with tracheobronchial amyloidosis are presented and the pathological features described. The congophilia of these forms of amyloid is resistant to potassium permanganate, compatible with it representing immunoamyloid. This, together with the associated intense lymphocytic and plasma cell infiltration suggests a local inflammatory aetiology.     

Familial hemophagocytic reticulosis. Clinicopathologic findings and cytochemical, immunohistochemical and electron microscopic studies

Clinicopathologic findings of a case of familial hemophagocytic reticulosis (FHR), for which splenectomy, and biopsy of the liver and mesenteric lymph nodes were performed, is reported. Histologically, the proliferated cells consisted of not only histiocytes showing severe erythrophagocytosis, but also lymphoid cells of various sizes. The lymphoid cells had atypical features including mitotic figures and convoluted nuclei, and were suspected to be T cells as a result of immunohistochemical studies. We therefore consider that FHR is a special type of lymphoproliferative disease accompanied by severe proliferation of erythrophagocytic histiocytes rather than being a true histiocytic disease. Cytochemical and electron microscopic findings of the involved spleen are also presented.     

Endocervical adenomyoma. A case report with histochemical and immunohistochemical studies

We report a case of adenomyoma of endocervical type arising in a 44-year-old female. Grossly, a well-circumscribed tumor protruding from the right side of the uterine cervix was seen which was assumed to be an ovarian tumor by imaging studies carried out preoperatively. The tumor was composed of a mixture of proliferating glands of endocervical type and fascicles of smooth muscle cells. There was no distinct nuclear anaplasia in the proliferating glands, there were no architectural abnormalities, and there was no evidence of destructive stromal invasion such as desmoplasia. Minimal deviation adenocarcinoma, which shows a gastric phenotype with immunoreactivity for M-GGMC-1 and predominantly PAS-positive neutral mucin, was a serious diagnostic possibility, but the lesion was well-circumscribed, cytologic and architectural abnormalities were absent, and staining for M-GGMC-1 was negative, which suggested a diagnosis of endocervical adenomyoma. An increased Ki-67 labeling index by up to 20%, the presence of predominantly PAS-positive neutral mucin, and membranous immunoreactivity for CEA in limited areas were diagnostic pitfalls, which could lead to an erroneous diagnosis of minimal deviation adenocarcinoma of the uterine cervix. Therefore, the results of these ancillary techniques should be interpreted with caution and combined with gross and light microscopic features.     

Low-grade renal cell carcinoma arising from the lower nephron: a case report with immunohistochemical, histochemical and ultrastructural studies

Most renal cell carcinomas (RCC) are composed of clear cells with sinusoid-like vasculatures and originate from the proximal tubule. On the other hand, collecting duct carcinoma (CDC) and chromophobe RCC are thought to originate from the lower nephron. In the present study, we present a case of unusual RCC. The patient was a 68-year-old Japanese woman who had developed general fatigue with hematuria. Computed tomography revealed a left renal tumor suggesting sarcoma. The resected tumor was located in the renal parenchyma, measuring 12 x 10 x 8 cm in size. Histologically, the tumor consisted principally of cuboidal cells forming parallel or radiating arrays, continuous with the spindle-shaped cells. Most parts of the tumor showed hemorrhagic necrosis. Immunohistochemically, tumor cells were positive for high molecular weight cytokeratins, vinculin, vimentin, CD15 and epithelial membrane antigen, and showed affinities with some kinds of lectins. N- and E-cadherins and beta-catenin were diffusely positive in tumor cells. Nuclear positivity for Ki-67 and p53 protein were approximately 2.0 and 1.7%, respectively. Considering its morphological and histochemical natures, this tumor is considered to have originated from the lower nephron, which is unique for a tumor of low-grade malignancy.     

Development of the notochord in human embryos: ultrastructural, histochemical, and immunohistochemical studies

In the present study of the notochord, the specimens were 54 externally normal human embryos ranging between Carnegie stages 13 and 23. The following staining procedures were used: periodic acid-Schiff (PAS), modified method of PAS, alcian blue, colloidal iron, and toluidine blue. Routine electron microscopic techniques were used. Immunoreactivity of the notochord to alpha-enolase was also examined. The notochord cells were undifferentiated in stage 13 with few intracellular organelles. The microfibrils and deposition of acid mucopolysaccharides appeared in the notochordal sheath in stage 14. The characteristic relation of mitochondria with rough endoplasmic reticulum was observed. Golgi complexes increased in the perinuclear region in stage 15. The layer of microfibrils in the notochordal sheath initially separated from the notochord in stage 16. Glycogen, mucoprotein, neutral mucopolysaccharides, and glycolipids began to increase in the mesenchymal cells around the notochord, starting at stage 16. Acid mucopolysaccharides increased in the notochordal sheath and in the matrix of the precartilage area around the notochord as this embryonic stage advanced. It was also revealed that the immunoreactivity of the notochord to alpha-enolase remained constant during the embryonic period. The results show that the notochord is transformed from an apparently undifferentiated organ into an organ with secretory activity in stage 14, producing microfibrils and depositing acid mucoplysaccharides in the notochordal sheath. The immunoreactivity of the notochord to alpha- and gamma-enolase isoenzymes and the development of the notochord are discussed. This study was undertaken to provide additional information on the development of tumors of notochordal origin.     

Metanephric adenoma of the kidney: Ultrastructural, immunohistochemical and lectin histochemical studies

A case of metanephric adenoma, a rare benign tumor of the kidney is reported, and the results of ultrastructural, immunohistochemical, and lectin histochemical studies are presented. The patient was a 47 year old Japanese man presenting wlth a left renal tumor by ultrasonography. The nephrectomy material revealed a well-demarcated tumor with medullary appearance, and on histological examination the tumor was composed of cuboidal cells forming regular small tubules with hyallnous stroma. Incomplete glomeruloid structures were formed in a few elongated tubules com-posed of columnar cells. Metanephric blastema was not observed in the tumor or in the normal kidney. By electron microscope, the tumor cells were observed to be immature cells with microvilli at the apical surfaces. The neoplastic tubules were surrounded by basal lamina. The tumor cells were immunoreactive for Leu 7, epithelial membrane antigen, vimentin, and low molecular weight cytokeratin, and were weakly immunoreactive for S-100 protein. Peanut agglutinin, soybean agglutinin, and Dollchos bifiorus agglu-tinin were bound to the apical surfaces of the tumor cells.     

Histological,histochemical, and immunohistochemical studies of hippocampus in male New Zealand rabbits

The present study aims to give detailed histomorphological features of the hippocampus of adult male New Zealand rabbits. Both histological and histochemical specimens were prepared to be examined microscopically by using a light microscope. The hippocampus appeared as C-shaped hippocampal proper, dentate gyrus, and subiculum. The hippocampal proper subdivided along its length according to the density and size of its major constituent pyramidal cells into four distinct regions named Cornu Ammonis (CA1, CA2, CA3, and CA4). With the histochemical preparations, each of these regions consisted of five layers, stratum alveolus, stratum oriens, stratum pyramidale, stratum radiatum, and stratum lacunosum-moleculare. The stratum pyramidale constituted the middle dark zone and contained the principal excitatory neurons and a few interneurons. Histochemically, the pyramidal neurons along all regions of the CA reacted positively to Grimelius silver impregnation, lead hematoxylin, Gomori's aldehyde fuchsin, aldehyde thionine, Gomori's chrome alum hematoxylin, and performic acid alcian blue stains. Immunohistochemically, the pyramidal neurons reacted positively to anti-NSE antibodies. The dentate gyrus was formed of three distinct layers. The subiculum was formed of proper subiculum, presubiculum, and parasubiculum.     

Predicting the duration of symptoms in lower respiratory tract infection.

BACKGROUND: Acute lower respiratory tract infection (LRTI) presenting in primary care has a long natural history. Antibiotic treatment makes little or no difference to the duration of cough. Limited information is currently available regarding predictors of illness duration. AIM: To determine predictors of illness duration in acute LRTI in primary care. DESIGN OF STUDY: Secondary analysis of trial data to identify independent predictors of illness severity and duration. SETTING: Primary care. METHOD: Eight-hundred and seven patients aged 3 years and over with acute illness (21 days or less) presenting with cough as the main symptom plus at least one symptom or sign from sputum, chest pain, dyspnoea, or wheeze were recruited to the study. Main outcomes were duration of symptoms (rated at least a slight problem) and more severe symptoms (rated at least moderately bad). RESULTS: The average duration of cough (rated at least a slight problem) was 11.7 days and was shorter among children (duration -1.72 days; 95% confidence interval [CI] = -3.02 to -0.41) or in individuals with a history of fever (-1.22 days; 95% CI = -0.18 to 2.27). The duration of cough was longer among those with restricted activities on the day they saw the doctor (+0.69 days for each point of a 7-point scale). The duration of more severe symptoms was longer in those with a longer duration of symptoms prior to consultation, with a more severe cough on the day of seeing the doctor, and restriction of activities on the day of seeing the doctor. CONCLUSION: Illness duration may be predicted from a limited number of clinical symptoms and from prior history. These findings should be subjected to validation in a separate population. To minimise expectation about rapid resolution of illness, adults who have restricted activities could be advised that they are likely to experience symptoms for longer.     

Localized amyloidosis of the lower genitourinary tract: a clinicopathological and immunohistochemical study of nine cases

A series of nine cases of localized amyloidosis of the lower genitourinary tract are reported. The patients comprised six males and three females with an age range of 50-79 years at initial presentation. Clinically and on cystoscopy, the lesions were often diagnosed as neoplasms. Histologically, seven cases had typical features of localized amyloid deposits, while two cases had an unusual appearance with a florid histiocytic and giant cell reaction. Using an immunoperoxidase staining method the deposits were non-reactive with antibodies to serum amyloid A protein, prealbumin and beta 2 microglobulin, while equivocal immunoreactivity was seen with anti-light chain antibodies.     

WU polyomavirus in children with acute lower respiratory tract infections, China.

BACKGROUND: WU polyomavirus (WUPyV), a new member of the genus of Polyomavirus in the family Polyomaviridae, has been found and associated with respiratory tract infections recently. However, its clinical role and pathogenicity has not been known. OBJECTIVES: To confirm that WU polyomavirus has been found in Chinese children. STUDY DESIGN: WU polyomavirus was detected and identified using PCR methods. A total of 278 specimens of nasopharyngeal aspirate were collected, and then PCR products were sequenced directly. RESULTS: One of 278 nasopharyngeal aspirates was positive for WUPyV in one child, and the positive rate was 0.4%. The results showed that the sequences of genome, LTAg and VP2 gene was identical to the reference sequences of WU polyomavirus prototype strains. CONCLUSIONS: We confirmed that WU polyomavirus had been found and identified in the respiratory secretions in China.