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91.
Barbashina V Heller DS Hameed M Albanese E Goldstein M Dashefsky B Dieudonne A Chakraborty R 《Virchows Archiv : an international journal of pathology》2000,436(2):138-139
Smooth-muscle neoplasms are rarely located in the spleen. They have been previously reported in five cases of children with
human immunodeficiency virus (HIV) infection/acquired immunodeficiency syndrome (AIDS). Two cases of children with HIV infection/AIDS
with autopsy and surgical pathology evidence of multiple smooth-muscle neoplasms with splenic involvement are presented. DNA
was extracted from histology slides in both cases for analysis for Epstein Barr (EB) virus. In both cases, the presence of
EB virus was confirmed. This paper documents two additional cases of the unusual phenomenon of splenic involvement by smooth-muscle
neoplasms in the setting of AIDS in childhood and further supports the role of EB virus in the development of these neoplasms.
Received: 27 January 1999 / Accepted: 23 August 1999 相似文献
92.
Anupama Kohli MD Stephen P. Baker MCS MPH Nilima A. Patwardhan MD Ashraf Khan MD MRCPATH 《Endocrine pathology》1998,9(2):117-123
Previous studies have established that thyroid follicular neoplasms of higher malignant potential show a high p53 and low
bc1-2 expression. This however has not been well studied in Oncocytic (Hürthle cell) neoplasms, the management of which remains
controversial. We therefore studied the expression of p53 and bc1-2 in 18 Hürthle cell adenomas (HCA) and 8 Hürthle cell carcinomas
(HCC) and compared them with their benign and malignant counterparts, respectively, including 16 follicular adenomas (FA)
and 68 papillary carcinomas (PC). All 16 FA were bc1-2 positive, 4 were 2+, and 12 were 3+. On the other hand, 14/18 (78%)
HCA showed bc1-2 expression, 5 were 1+, 6 were 2+, and only 3 were 3_. Similarly, HCC showed a weaker bc1-2 staining pattern
compared to PC. Only 1 FA showed grade 1, p53 staining, the remaining 15 were negative, and 15/18 HCA showed p53 expression
of varying grades. This difference in p53 staining was statistically significant (p=0.005). A significant p53 overexpression was also seen in HCC compared to PC (p=0.005). In conclusion, there appears to be an inverse relationship between p53 and bc1-2 expression in thyroid follicular
neoplasms. A higher expression of p53 and lower levels bc1-2 in Hürthle cell neoplasms may have biological and clinical implications.
This may support a more aggressive surgical treatment for HCA compared to FA. 相似文献
93.
94.
Renate Wachner Christian Wittekind Sabine von Kleist 《Virchows Archiv : an international journal of pathology》1984,402(4):415-423
Summary One hundred and twenty seven cases of lung tumors were studied by the immunoperoxidase technique for the presence of CEA and-HCG. Twenty-nine of these tumors were additionally stained for keratin and SP1. CEA and SP1 could be demonstrated in 80% of the studied cases, while-HCG was found in only 9%. SP1 revealed an almost identical staining pattern to CEA and keratin was found only in squamous cell carcinomas. The tissue positivity of none of these three markers correlated with tumor size, lymphnodal involvement or histological type.This study was supported by Deutsche Stiftung für Krebsforschung - Dr. Mildred Scheel-Stiftung 相似文献
95.
Reiji Haba Shoji Kobayashi Eiichiro Hlrakawa Hiroshi Miki Takeshi Okino Tatsuo Kurokawa Syuu Yamamoto 《Pathology international》1996,46(7):515-519
An extremely rare case of malignant fibrous histiocytoma In the pancreas Is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 × 7 × 6.5cm in size. Microscopically, fibroblastic, histiocytic, and muitinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphlc pattern. Immunohtstochemically, some tumor cells were positive for lysozyme, α-1-antitrypsin, α-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient Is currently well with no evidence of recurrence or metastasis 22 months after operation. 相似文献
96.
P. Stömmer 《Journal of molecular medicine (Berlin, Germany)》1989,67(3):136-140
Summary Phospholipase A2 is an enzyme which is produced in acinar cells, and persists even in regressive states of chronic pancreatitis, when the production of other enzymes diminishes. We therefore tested this enzyme as a marker of acinar descent in various pancreatic tumors. This enzyme could be seen in 50% of the acinar-cell carcinomas, in 60% of solid and papillary pancreatic tumors, and in 50% of microglandular carcinomas. Ductal cancers and isletcell cancers were negative. In contrast to other markers of acinar matrix (amylase, antitrypsin), phospholipase A2 gave fewer false-positive or false-negative results.Supported by a grant of the J. and F. Marohn Stiftung at the University of Erlangen/Nürnberg 相似文献
97.
Masafumi Ito Atsuko Nakagawa Atsuo Nakayama Yutaka Uno Izumi Takahashi Junpei Asai 《Pathology international》1990,40(2):149-152
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990. 相似文献
98.
Microvascular structural entropy: A novel approach to assess angiogenesis in pituitary tumors 总被引:2,自引:0,他引:2
Entropy, a measure of the degree of disorder in a system, has recently been used in different morphologic studies to quantify
regularity. Our aims were (a) to study the structural organization of the microvascular bed in prolactin (PRL)-producing adenomas
and carcinomas, the most vascularized of pituitary tumors, by assessing microvascular structural entropy (MSE), and (b) to
determine whether the degree of disorder of the capillary bed correlates with tumor cell proliferation as estimated by MIB-1
labeling, microvessel density (MVD), the most widely used method of quantifying blood vessel formation, and various clinicopathologic
parameters (gender, age, tumor size and invasiveness). The morphometric study demonstrated statistically significant differences
in MIB-1 labeling, MVD, and MSE between PRL-producing adenomas and carcinomas. Unlike MIB-1 labeling index (PRL-producing
adenomas 1.5±0.27; carcinomas 15.0±4.04) and MVD (PRL-producing adenomas 2.7±0.34; carcinomas 4.2±0.72), the MSE values were
significantly higher in adenomas (171.5±25.37) than in carcinomas (67.9±17.45). These results indicate that PRL-producing
carcinomas have a less chaotic distribution of vessels than benign adenomas. In contrast to a lack of correlation between,
microvessel density and other morphometric parameters, a strong negative correlation was found between MSE and MIB-1 labeling
index (r=0.511, p=0.003). It thus appears that regular, less chaotic microvascular geometry contributes to increased proliferative activity
in PRL cell tumors. Analysis of MSE may provide an independent parameter of tumor behavior, and contributes to a better understanding
of the role of microvasculature in pituitary tumor progression. 相似文献
99.
Terracciano LM Bernasconi B Ruck P Stallmach T Briner J Sauter G Moch H Vecchione R Pollice L Pettinato G Gürtl B Ratschek M De Krijger R Tornillo L Bruder E 《Human pathology》2003,34(9):864-871
Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm. 相似文献
100.
Radcliffe Jerilynn; Bennett David; Kazak Anne E.; Foley Bernadette; Phillips Peter C. 《Journal of pediatric psychology》1996,21(4):529-539
Examined the adjustment of 6- to 18-year-old children and adolescents(n = 38) 2 to 5 years postdiagnosis of brain tumor with respectto standardized measures of anxiety and depression; self-perceptions;and adaptive living skills. Child, mother, and teacher reportdata were used. Maternal adjustment (anxiety and depression,parenting stress) was also assessed. Children and adolescentssurviving brain tumors reported themselves to be generally withinthe normal range. However, maternal ratings of social problemswere higher than normative scores and significantly lower thannorms on social problems, scholastic competence, and communicationskills. Teacher ratings on the Teacher Rating Form were allwithin normal limits. Maternal adjustment measures were withinthe normal range, although the Parent-Child Dysfunctional Interactionsubscale of the Parenting Stress Index was elevated. No differencesin scores were found between children in regular and specialeducation, or between children who had received radiation andthose who did not. This sample of survivors of pediatric braintumors and their mothers had relatively mild problems in adjustment,supporting a competency-based view of the adaptation of pediatricpatients and their families. 相似文献