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1.
Cochrane Database Syst Rev ; (3): CD001938, 2007 Jul 18.
Article in English | MEDLINE | ID: mdl-17636690

ABSTRACT

BACKGROUND: Atrial fibrillation (AF) carries a high risk of stroke and other thromboembolic events. Appropriate use of drugs to prevent thromboembolism in patients with AF involves comparing the patient's risk of stroke to the risk of hemorrhage from medication use. OBJECTIVES: To quantify risk of stroke, major hemorrhage and death from using medications that have been rigorously evaluated for prevention of thromboembolism in AF. SEARCH STRATEGY: Articles were identified through the Cochrane Collaboration's CENTRAL database and MEDLINE until December 1999. SELECTION CRITERIA: Included Randomized controlled trials of drugs to prevent thromboembolism in adults with non-postoperative AF. Excluded RCTS of patients with rheumatic valvular disease. DATA COLLECTION AND ANALYSIS: Data were abstracted by two reviewers. Odds ratios from all qualitatively similar studies were combined, with weighting by study size, to yield aggregate odds ratios for stroke, major hemorrhage, and death for each drug. MAIN RESULTS: Fourteen articles were included in this review. Warfarin was more efficacious than placebo for primary stroke prevention {aggregate odds ratio (OR) of stroke=0.30 [95% Confidence Interval (C.I.) 0.19,0.48]}, with moderate evidence of more major bleeding { OR= 1.90 [95% C.I. 0.89,4.04].}. Aspirin was inconclusively more efficacious than placebo for stroke prevention {OR=0.68 [95% C.I. 0.29,1.57]}, with inconclusive evidence regarding more major bleeds {OR=0.81[95% C.I. 0.37,1.78]}. For primary prevention, assuming a baseline risk of 45 strokes per 1000 patient-years, warfarin could prevent 30 strokes at the expense of only 6 additional major bleeds. Aspirin could prevent 17 strokes, without increasing major hemorrhage. In direct comparison, there was moderate evidence for fewer strokes among patients on warfarin than on aspirin {aggregate OR=0.64[95% C.I. 0.43,0.96]}, with only suggestive evidence for more major hemorrhage {OR =1.58 [95% C.I. 0.76,3.27]}. However, in younger patients, with a mean age of 65 years, the absolute reduction in stroke rate with warfarin compared to aspirin was low (5.5 per 1000 person-years) compared to an older group (15 per 1000 person-years). Low-dose warfarin or low-dose warfarin with aspirin was less efficacious for stroke prevention than adjusted-dose warfarin. AUTHORS' CONCLUSIONS: The evidence strongly supports warfarin in AF for patients at average or greater risk of stroke, although clearly there is a risk of hemorrhage. Although not definitively supported by the evidence, aspirin may prove to be useful for stroke prevention in sub-groups with a low risk of stroke, with less risk of hemorrhage than with warfarin. Further studies are needed of low- molecular weight heparin and aspirin in lower risk patients.


Subject(s)
Anticoagulants/therapeutic use , Atrial Fibrillation/complications , Atrial Flutter/complications , Hemorrhage/prevention & control , Platelet Aggregation Inhibitors/therapeutic use , Stroke/prevention & control , Thromboembolism/prevention & control , Confidence Intervals , Hemorrhage/etiology , Humans , Odds Ratio , Randomized Controlled Trials as Topic , Stroke/etiology , Thromboembolism/etiology
2.
Nat Biotechnol ; 19(1): 78-81, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11135558

ABSTRACT

The analysis of loss of heterozygosity (LOH) is perhaps the most widely used technique in cancer genetics. In primary tumors, however, the analysis of LOH is fraught with technical problems that have limited its reproducibility and interpretation. In particular, tumors are mixtures of neoplastic and nonneoplastic cells, and the DNA from the nonneoplastic cells can mask LOH. We here describe a new experimental approach, involving two components, to overcome these problems. First, a form of digital PCR was employed to directly count, one by one, the number of each of the two alleles in tumor samples. Second, Bayesian-type likelihood methods were used to measure the strength of the evidence for the allele distribution being different from normal. This approach imparts a rigorous statistical basis to LOH analyses, and should be able to provide more reliable information than heretofore possible in LOH studies of diverse tumor types.


Subject(s)
Chromosomes, Human, Pair 18 , Colorectal Neoplasms/genetics , DNA, Neoplasm/genetics , Loss of Heterozygosity , Neoplasm Invasiveness/genetics , Polymorphism, Single Nucleotide , Alleles , Bayes Theorem , Colorectal Neoplasms/pathology , Humans , Likelihood Functions , Neoplasm Staging , Polymerase Chain Reaction/methods
3.
J Natl Cancer Inst ; 88(21): 1580-6, 1996 Nov 06.
Article in English | MEDLINE | ID: mdl-8901856

ABSTRACT

BACKGROUND: The p53 gene (also known as TP53) may be the most common genetic target involved in the malignant transformation of human cells. Direct sequence analysis has demonstrated that alteration of this gene occurs in approximately 45% of head and neck squamous cell carcinomas. The consequences of p53 mutations in these cancers with respect to tumor behavior and patient survival have not been rigorously determined. PURPOSE: We evaluated the implications of p53 mutations in relation to the control of locoregional disease and overall survival following radiation therapy. METHODS: Data from 110 consecutive patients with invasive disease who were treated with primary radiation therapy (given with curative intent) or with adjuvant radiation therapy (following complete surgical extirpation of gross disease) were included in the analysis. A 1.8-kilobase fragment of the p53 gene encompassing exons 5-9 was amplified from the DNA of stored (frozen) tumor specimens; the amplified DNA was cloned and sequenced by use of standard techniques. Overall survival and locoregional disease-free survival after the completion of radiation therapy were estimated by the Kaplan-Meier method; survival comparisons were made by use of the logrank test or proportional hazards regression models. Reported P values are two-sided. RESULTS: Fortyeight (44%) of the 110 tumors had cells bearing p53 mutations. The risk of locoregional recurrence following either primary or adjuvant radiation therapy was significantly greater (i.e., the time to recurrence was shorter) for patients whose tumors contained mutant p53 genes (univariate model hazard ratio [HR] for p53 mutation versus wild-type = 2.2; 95% confidence interval [CI] = 1.2-4.1; P = .02). The presence of regional lymph node metastases (presence versus absence, HR = 2.0; 95% CI = 1.0-4.2; P = .05) and treatment type (primary radiation therapy versus surgery plus adjuvant radiation therapy, HR = 2.3; 95% CI = 1.2-4.3; P = .01) were also associated with greater risks of locoregional failure. The presence of p53 mutations and lymph node metastases and treatment with primary, as opposed to adjuvant, radiation therapy remained significant risk factors in multivariate regression analysis. No relationship was demonstrated between p53 status and overall survival (mutant versus wild-type, HR = 1.1; 95% CI = 0.6-2.1; P = .66); however, a relationship was shown for tumor stage and overall survival (stages III and IV [more advanced] versus stages I and II [less advanced], HR = 3.3; 95% CI = 1.0-10.8; P = .05). Mutation of the p53 gene was not associated with patient age, sex, tumor stage, primary tumor site, regional lymph node status, degree of tumor cell differentiation, or treatment method. CONCLUSIONS: Mutation of the p53 gene is associated with an increased risk of locoregional failure in patients with invasive head and neck squamous cell carcinoma who are treated with radiation therapy.


Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/therapy , Genes, p53/genetics , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/therapy , Mutation , DNA, Neoplasm/genetics , Disease-Free Survival , Humans , Polymerase Chain Reaction , Survival Analysis , Treatment Failure
4.
J Natl Cancer Inst ; 93(11): 858-65, 2001 Jun 06.
Article in English | MEDLINE | ID: mdl-11390535

ABSTRACT

BACKGROUND: Colorectal cancer cells are shed into the stool, providing a potential means for the early detection of the disease using noninvasive approaches. Our goal was to develop reliable, specific molecular genetic tests for the detection of colorectal cancer in stool samples. METHODS: Stool DNA was isolated from paired stools and primary tumor samples from 51 colorectal cancer patients. Three genetic targets-TP53, BAT26, and K-RAS-were used to detect tumor-associated mutations in the stool prior to or without regard to the molecular analyses of the paired tumors. TP53 gene mutations were detected with a mismatch-ligation assay that detects nine common p53 gene mutations. Deletions within the BAT26 locus were detected by a modified solid-phase minisequencing method. Mutations in codons 12 and 13 of K-RAS were detected with a digital polymerase chain reaction-based method. RESULTS: TP53 gene mutations were detected in the tumor DNA of 30 patients, all of whom had the identical TP53 mutation in their stools. Tumors from three patients contained a noninherited deletion at the BAT26 locus, and the same alterations were identified in these patients' stool specimens. Nineteen of 50 tumors tested had a K-RAS mutation; identical mutations were detected in the paired stool DNA samples from eight patients. In no case was a mutation found in stool that was not also present in the primary tumor. Thus, the three genetic markers together detected 36 (71%) of 51 patients (95% confidence interval [CI] = 56% to 83%) with colorectal cancer and 36 (92%) of 39 patients (95% CI = 79% to 98%) whose tumors had an alteration. CONCLUSION: We were able to detect the majority of colorectal cancers by analyzing stool DNA for just three genetic markers. Additional work is needed to determine the specificity of these genetic tests for detecting colorectal neoplasia in asymptomatic patients and to more precisely estimate the prevalence of the mutations and sensitivity of the assay.


Subject(s)
Colonic Neoplasms/diagnosis , Colonic Neoplasms/genetics , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , DNA/genetics , Feces/chemistry , Genes, p53 , Genes, ras , Mutation , Aged , Colonic Neoplasms/pathology , Colorectal Neoplasms/pathology , DNA/isolation & purification , Genetic Markers , Germ-Line Mutation , Humans , Middle Aged , Neoplasm Staging , Polymerase Chain Reaction/methods , Reproducibility of Results , Sequence Deletion
5.
Cancer Res ; 61(3): 818-22, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11221861

ABSTRACT

Chromosomal instability is believed to be a common feature of most human tumors, but the stage at which such instability originates has not been defined. At the molecular level, chromosomal instability is characterized by allelic imbalance (AI), representing losses or gains of defined chromosomal regions. We have assessed AI in early colorectal tumors using newly developed methods for assessing AI in complex cell populations. A total of 32 adenomas of average size (2 mm; range, 1-3 mm) were studied. AI of chromosome 5q markers occurred in 55% of tumors analyzed, consistent with a gatekeeping role of the adenomatous polyposis coli tumor suppressor gene located at chromosomal position 5q21. AI was also detected in each of the other four chromosomes tested. The fractions of adenomas with AI of chromosomes 1p, 8p, 15q, and 18q were 10,19, 28, and 28%, respectively. Over 90% of the tumors exhibited AI of at least one chromosome, and 67% had allelic imbalance of a chromosome other than 5q. These findings demonstrate that AI is a common event, even in very small tumors, and suggest that chromosomal instability occurs very early during colorectal neoplasia.


Subject(s)
Adenoma/genetics , Allelic Imbalance , Colorectal Neoplasms/genetics , Adenoma/pathology , Colorectal Neoplasms/pathology , DNA Primers , DNA, Neoplasm/genetics , Genetic Markers/genetics , Humans , Polymerase Chain Reaction/methods , Polymorphism, Single Nucleotide , Probability
6.
Cancer Res ; 57(9): 1731-4, 1997 May 01.
Article in English | MEDLINE | ID: mdl-9135016

ABSTRACT

During tumorigenesis, positive selection is exerted upon those tumor cells that alter rate-limiting regulatory pathways. A corollary of this principle is that mutation of one gene abrogates the need for alteration of another gene in the same pathway and also that the coexistence in a single tumor of mutations in different genes implies their involvement in distinct tumor-suppressive pathways. We studied 42 pancreatic adenocarcinomas for genetic alterations in the K-ras oncogene and the p16, p53, and DPC4 tumor suppressor genes. All of them had the K-ras gene mutated. Thirty-eight % of the tumors had four altered genes, another 38% had three altered genes, 15% had two altered genes, and 8% of the tumors had one altered gene. Interestingly, we noted a high concordance of DPC4 and p16 inactivations (P = 0.007), suggesting that the genetic inactivation of p16 increases the selective advantage of subsequent mutation in DPC4. No statistically significant association was identified between the alteration of these cancer genes and pathological or clinical parameters. This type of multigenic analysis in human tumors may serve to substantiate experimental tumor models and thus increase our understanding of the truly physiologically relevant tumor-suppressive pathways that are abrogated during human tumorigenesis.


Subject(s)
Adenocarcinoma/genetics , DNA-Binding Proteins , Genes, Tumor Suppressor , Pancreatic Neoplasms/genetics , BRCA2 Protein , Carrier Proteins/genetics , Cyclin-Dependent Kinase Inhibitor p16 , DNA Mutational Analysis , DNA, Neoplasm/genetics , Female , Genes, p53 , Genes, ras , Heterozygote , Humans , Male , Neoplasm Proteins/genetics , Sequence Deletion , Smad4 Protein , Trans-Activators/genetics , Transcription Factors/genetics
7.
Clin Cancer Res ; 4(1): 21-9, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9516948

ABSTRACT

CD44, a cell hyaluronate receptor, is implicated in the metastatic behavior of some cancer cells. This study analyzed CD44 expression in topographic tissue sites of colorectal cancers to determine its association with patient survival and clinicopathological characteristics. Immunohistochemical localization of the core CD44 and the v6 splice variant domains was examined by use of paraffin-fixed sections from 133 stage II or III colorectal cancers that previously had been evaluated for other diagnostic markers. Expression in malignant epithelium, stromal matrix, and stromal cells was compared to patient survival by univariate, multivariate, and bootstrap (reproducibility) analysis. Core CD44 staining was present in the malignant epithelium of 85% of tumors, the stromal matrix of 90%, and the stromal cells of 98%. The v6 splice variant domain was present in the epithelium of 77% of tumors but was less frequent in the stromal matrix (12%; P < 0.001) and stromal cells (17%; P < 0.001). Absence of core CD44 immunoreactivity in the stromal matrix was associated with increased death rate (hazard ratio, 2.4; 95% confidence interval, 1.2-4.8; P = 0.02), making this one of the most significant adverse prognostic variables, along with an age of 60 years or older, poor differentiation of the cancer, extramural venous invasion, chromosome 18q allelic loss, and nonwhite race. This study shows that core CD44 and v6 splice variant antigens are differentially expressed in the epithelium and stroma of colorectal cancers. A model that includes core CD44 immunoreactivity in stromal matrix along with other prognostic factors may improve identification of high-risk and low-risk patients.


Subject(s)
Colorectal Neoplasms/chemistry , Hyaluronan Receptors/analysis , Adult , Aged , Animals , Colorectal Neoplasms/mortality , Humans , Mice , Middle Aged , Prognosis , Proportional Hazards Models , Survival Rate
8.
Diabetes Care ; 19(1): 56-9, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8720535

ABSTRACT

OBJECTIVE: To determine if caretakers of young children with IDDM could consistently reproduce small incremental measurements of insulin (U100). RESEARCH DESIGN AND METHODS: Fifteen caretakers of children with IDDM were asked to deliver repeated small doses of insulin, including doses separated by only 0.25 U of insulin. A sensitive gravimetric technique was used to determine the error in measurement of these low doses of insulin. Statistical analysis was used to evaluate accuracy and internal consistency of each caretaker at each dose. RESULTS: The means +/- SD at each dose level were as follows: 2.75 +/- 0.13 U at 2.5 U, 3.19 +/- 0.13 U at 3.0 U, 3.55 +/- 0.13 U at 3.25 U, and 3.70 +/- 0.11 U at 3.5 U. All doses were biased toward overadministration. There was as statistically significant difference in the dose delivered when the target doses were varied by only 0.25 U. The average differences and standard errors between 2.5 U and 3.0 U, 3.0 U and 3.25 U, and 3.25 U and 3.5 U were 0.44 +/- 0.20 U, 0.36 +/- 0.018 U, and 0.15 +/- 0.017 U, respectively. CONCLUSIONS: Participants were not accurate in measuring small insulin doses, consistently overdrawing insulin by an average of 0.22 U. Caretakers are reasonably internally consistent with a given dose, since participants were able to measure statistically significant differences in 0.25 U dose changes. The error in insulin measurement does not vary with the intended dose level. Caretakers in the same family deliver insulin doses as variable from each other as they are from the population as a whole; however, when two or more individuals are responsible for one insulin dose in a child with IDDM, they have a combined variability that is approximately 40% greater than a single individual's variability.


Subject(s)
Caregivers , Diabetes Mellitus, Type 1/drug therapy , Hypoglycemic Agents/administration & dosage , Insulin/administration & dosage , Child , Child, Preschool , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Regression Analysis , Reproducibility of Results , Syringes
9.
Neurology ; 54(7): 1505-9, 2000 Apr 11.
Article in English | MEDLINE | ID: mdl-10751267

ABSTRACT

BACKGROUND: Ataxia telangiectasia (A-T) is a rare disorder with many distinctive neurologic features. Although there is substantial individual variation in the rate of progression of these features, their relationship to one another or to age has not been characterized. METHODS: We formulated and tested multiple elements that assess different neurologic functions known to be affected by A-T. The overall index was applied to 52 patients with A-T, 2 to 29 years of age. RESULTS: Seven elements items proved to be informative, and three elements were added based on face validity. In a linear regression model of individuals under 19 years of age, controlled for correlation within sibships, age accounted for 87% of the variation in the A-T Index. CONCLUSION: Despite substantial individual variability of the phenotypic elements of A-T, scores on this multidimensional index have a very high correlation with age, indicating that there is a characteristic rate of progression of the disease, although functional domains in the brain are differentially affected. The pattern of scores suggests that a severe and a mild form of A-T may be distinguished by this quantitative measure. With further development this index may become useful as an outcome measure for treatment studies and prognosis.


Subject(s)
Ataxia Telangiectasia/diagnosis , Neuropsychological Tests , Severity of Illness Index , Adolescent , Adult , Age Factors , Child , Child, Preschool , Cohort Studies , Data Interpretation, Statistical , Disease Progression , Humans , Infant , Linear Models , Observer Variation , Phenotype , Predictive Value of Tests , Prospective Studies , Reproducibility of Results
10.
J Immunol Methods ; 132(2): 275-86, 1990 Sep 14.
Article in English | MEDLINE | ID: mdl-1698878

ABSTRACT

We have developed a flow cytometric assay for the determination of cellular expression of terminal deoxynucleotidyl transferase (TdT) and applied this to the detection of minimal residual T cell acute lymphoblastic leukemia (T-ALL). The flow cytometric assay for TdT demonstrated requisite specificity: TdT was localized to the nucleus, and was detected in MOLT3 T lymphoblasts, clinical T-ALL samples, and normal bone marrow B lymphoid precursors, but in neither the KG1a myeloid leukemia cell line nor normal myeloid cells. Co-expression of TdT and the pan T cell marker CD5 was used to quantify T lymphoblasts. 0.25 +/- 0.13% of normal adult bone marrow CD5+ cells were TdT+; these may represent early T lymphoid precursors. When admixed with normal bone marrow, CD5+TdT+ leukemic cells could be detected above background levels at an added concentration of 0.035% (95% confidence interval 0.028-0.43%). Long term follow-up of a large number of patients will be required to determine the clinical significance of a minimal burden of leukemic cells.


Subject(s)
DNA Nucleotidylexotransferase/analysis , Leukemia-Lymphoma, Adult T-Cell/diagnosis , T-Lymphocytes/chemistry , Antibodies, Monoclonal , Antigens, CD/analysis , Antigens, CD34 , Antigens, Differentiation/analysis , Antigens, Neoplasm/analysis , Bone Marrow/pathology , Bone Marrow Cells , Flow Cytometry/methods , Humans , Leukemia-Lymphoma, Adult T-Cell/enzymology , Leukemia-Lymphoma, Adult T-Cell/pathology , Neprilysin , Time Factors , Tumor Cells, Cultured
11.
Am J Med ; 101(1): 68-76, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8686718

ABSTRACT

PURPOSE: To compare the efficacy and safety of inpatient oral antibiotic treatment (oral) versus standard parenteral antibiotic treatment (intravenous) for right-sided staphylococcal endocarditis in injection drug users. PATIENTS AND METHODS: In a prospective, randomized, non-blinded trial, febrile injection drug users were assigned to begin oral or intravenous (IV) treatment on admission, before blood culture results were available. Oral therapy consisted of ciprofloxacin and rifampin. Parenteral therapy was oxacillin or vancomycin, plus gentamicin for the first 5 days. Antibiotic dosing was adjusted for renal dysfunction. Administration of other antibacterial drugs was not permitted during the treatment or follow-up periods. Bacteremic subjects having right-sided staphylococcal endocarditis received 28 days of inpatient therapy with the assigned antibiotics. Test-of-cure blood cultures were obtained during inpatient observation 6 and 7 days after the completion of antibiotic therapy, and again at outpatient follow-up 1 month later. Criteria for treatment failure and for drug toxicity were prospectively defined. RESULTS: Of 573 injection drug users who were hospitalized because of a febrile illness and suspected right-sided staphylococcal endocarditis, 93 subjects (16.2%) had two or more sets of blood cultures positive for staphylococci; 85 of these bacteremic subjects (14.8%) satisfied diagnostic criteria for at least possible right-sided staphylococcal endocarditis (no other source of bacteremia was apparent) and entered the trial. Forty-four (oral, 19; IV, 25) of these 85 subjects completed inpatient treatment and evaluation including test-of-cure blood cultures. There were four treatment failures (oral, 1 [5.2%]; IV, 3 [12.0%]; not significant, Fisher's exact test). Drug toxicity was significantly more common in the parenterally treated group (oral, 3%; IV, 62%; P < 0.0001), consisting largely of oxacillin-associated increases in liver enzymes. CONCLUSIONS: For selected patients with right-sided staphylococcal endocarditis, oral ciprofloxacin plus rifampin is effective and is associated with less drug toxicity than is intravenous therapy.


Subject(s)
Anti-Infective Agents/administration & dosage , Endocarditis, Bacterial/drug therapy , Staphylococcal Infections/drug therapy , Substance Abuse, Intravenous/complications , Administration, Oral , Adult , Anti-Bacterial Agents/administration & dosage , Antibiotics, Antitubercular/administration & dosage , Ciprofloxacin/administration & dosage , Endocarditis, Bacterial/etiology , Endocarditis, Bacterial/mortality , Female , Gentamicins/administration & dosage , Humans , Infusions, Intravenous , Length of Stay , Male , Oxacillin/administration & dosage , Penicillins/administration & dosage , Prospective Studies , Rifampin/administration & dosage , Staphylococcal Infections/etiology , Staphylococcal Infections/mortality , Treatment Outcome , Vancomycin/administration & dosage
12.
Am J Surg Pathol ; 17(3): 213-20, 1993 Mar.
Article in English | MEDLINE | ID: mdl-8434702

ABSTRACT

Mutations in the p53 tumor suppressor gene are frequently observed in primary lung adenocarcinomas, suggesting that these mutations are critical events in the malignant transformation of airway cells. These mutations are often associated with stabilization of the p53 gene product, resulting in the accumulation of p53 protein. In this study, 70 formalin-fixed, paraffin-embedded primary lung adenocarcinomas resected for potential cure were examined for p53 overexpression. These 70 lung adenocarcinomas were obtained from a series of patients with well-documented clinical histories, and all 70 carcinomas had been previously evaluated for point mutations in codon 12 of the K-ras oncogene. Overexpression of the p53 protein was detected using an antigen retrieval system (Target Unmasking Fluid) and the anti-p53 antibody CM-1. CM-1 is a polyclonal antibody directed against the wild-type p53 protein. Overexpression of the p53 protein was found in 23 (33%) of the 70 lung adenocarcinomas. In all 23 cases, overexpression was confined to neoplastic cells. Overexpression of the p53 protein correlated with cigarette smoking: 10 (56%) of the 18 adenocarcinomas from patients who were current smokers overexpressed p53 compared with 13 (33%) of the 40 adenocarcinomas from patients who had quit smoking and 0 (0%) of the 12 adenocarcinomas from patients who had never smoked (p = 0.002, trend test). Overexpression of the p53 protein was also related to the degree of histologic differentiation: 48% of the p53 negative carcinomas were well differentiated, whereas only 13% (p = 0.003) of the carcinomas in which p53 was overexpressed were well differentiated. Overexpression of the p53 protein did not correlate with point mutations in codon 12 of the K-ras oncogene, nor did it correlate with tumor stage or patient survival. These findings indicate that p53 protein is frequently overexpressed in primary lung adenocarcinomas. Furthermore, the association of tobacco smoking with this overexpression suggests that the p53 gene is a target of specific mutagens in tobacco smoke.


Subject(s)
Adenocarcinoma/genetics , Genes, p53 , Lung Neoplasms/genetics , Smoking/adverse effects , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Codon , Female , Genes, ras/genetics , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Mutation , Neoplasm Staging , Survival Analysis
13.
Am J Surg Pathol ; 25(5): 579-86, 2001 May.
Article in English | MEDLINE | ID: mdl-11342768

ABSTRACT

Proliferative epithelial lesions in the smaller caliber pancreatic ducts and ductules have been the subject of numerous morphologic, clinical, and genetic studies; however, a standard nomenclature and diagnostic criteria for classifying these lesion have not been established. To evaluate the uniformity of existing systems for grading duct lesions in the pancreas, 35 microscopic slides with 35 representative duct lesions were sent to eight expert pathologists from the United States, Canada, and Europe. Kappa values for interobserver agreement could not be calculated initially because more than 70 different diagnostic terms were used by the eight pathologists. In several cases, the diagnoses rendered for a single duct lesion ranged from "hyperplasia," to "metaplasia," to "dysplasia," to "carcinoma in situ." This review therefore demonstrated the need for a standard nomenclature and classification system. Subsequently, during a working group meeting, the pathologists agreed to adopt a single standard system. The terminology pancreatic intraepithelial neoplasia (or PanIN) was selected, and diagnostic criteria for each grade of PanIN were established (http://pathology.jhu.edu/pancreas_panin). This new system was then evaluated by having the eight pathologists rereview the original 35 cases. Only seven different diagnoses were rendered, and kappa values of 0.43, 0.14, and 0.42 were obtained for PanINs 1, 2, and 3 respectively. Cases assigned other diagnoses (e.g., squamous metaplasia) collectively had a kappa value of 0.41. These results show both the potential of the classification system, and also the difficulty of classifying these lesions even with a consistent nomenclature. However, even when there is lack of consensus, having a restricted set of descriptions and terms allows a better understanding of the reasons for disagreement. It is suggested that we adopt and apply this system uniformly, with continued study of its reliability and use, and possibly further refinement. The acceptance of a standard classification system will facilitate the study of pancreatic duct lesions, and will lead ultimately to a better understanding of their biologic importance.


Subject(s)
Carcinoma in Situ/classification , Pancreatic Ducts/pathology , Pancreatic Neoplasms/classification , Precancerous Conditions/classification , Terminology as Topic , Carcinoma in Situ/pathology , Humans , Observer Variation , Pancreatic Neoplasms/pathology , Precancerous Conditions/pathology , Reference Standards
14.
Am J Surg Pathol ; 18(4): 338-46, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8141428

ABSTRACT

Accelerated arteriosclerosis is now the major long-term complication of heart transplantation. Defining the risk factors associated with the development of accelerated arteriosclerosis will provide not only a means of identifying patients at risk for this complication but also clues to the etiology of accelerated arteriosclerosis. The purpose of this study was to examine the relationship between peritransplant myocardial ischemic injury and the development of accelerated arteriosclerosis. In a case-control study we examined the first three endomyocardial biopsies from 50 heart transplant recipients and graded the degree of ischemic injury present in these biopsies. The histologic changes graded in the biopsies included contraction band necrosis, coagulative necrosis, and macrophagic removal of ischemically injured myocytes. Of the 50 recipients included in the study, 25 had angiographic evidence of accelerated arteriosclerosis and 25 did not. In multivariate analysis, which included the number of class I major histocompatibility (MHC) antigen mismatches between the donor and the recipient, the recipient's post-transplant cytomegalovirus status, the donor's age, and the number of rejection episodes, the histologic degree of ischemic injury present in the biopsies emerged as the strongest predictor of the development of accelerated arteriosclerosis (RR 2.6, 95% CI 1.2-5.8, p = 0.02). These results suggest that ischemic injury to the heart during the peritransplant period significantly contributes to the development of accelerated arteriosclerosis in heart transplant recipients and that histologic changes in early posttransplant biopsies can be used to identify recipients at risk of developing accelerated arteriosclerosis.


Subject(s)
Coronary Artery Disease/pathology , Heart Transplantation/pathology , Intraoperative Complications/pathology , Myocardium/pathology , Postoperative Complications/pathology , Adolescent , Adult , Biopsy , Case-Control Studies , Coronary Artery Disease/etiology , Cytomegalovirus Infections/complications , Female , Graft Rejection , Heart Transplantation/adverse effects , Heart Transplantation/immunology , Histocompatibility , Humans , Male , Middle Aged , Multivariate Analysis , Myocardial Ischemia/etiology , Myocardial Ischemia/pathology , Necrosis
15.
Am J Cardiol ; 67(5): 391-7, 1991 Feb 15.
Article in English | MEDLINE | ID: mdl-1825259

ABSTRACT

To determine whether dilated cardiomyopathy, myocarditis or cardiac transplantation affect the relation between plasma immunoreactive atrial natriuretic factor (ANF) and cardiac filling pressures, right atrial plasma ANF concentration, pulmonary arterial wedge pressure and right atrial pressure were measured in patients with dilated cardiomyopathy (n = 48), dilated cardiomyopathy secondary to myocarditis (n = 20) and prior cardiac transplantation (n = 34). ANF level significantly correlated with both pulmonary arterial wedge and right atrial pressures in patients with dilated cardiomyopathy; however, the presence or absence of myocarditis did not significantly alter these relations (p = 0.88 and p = 0.33 for interaction terms, respectively). For the combined group the ANF-pulmonary arterial wedge pressure relation had a slope of 8.1 pg/ml/mm Hg (95% confidence interval (CI), 5.4 to 10.8; p = 0.0001) and the ANF-right atrial pressure relation a slope of 13.6 pg/ml/mm Hg (CI, 8.5 to 18.7; p = 0.0001). Receiver operator curve analysis identified an optimal dividing point of ANF 150 pg/ml with 100% (CI, 72 to 100%) of patients with right atrial pressure greater than or equal to 8 mm Hg having ANF greater than or equal to 150 pg/ml, but only 56% (CI, 42 to 69%) with pressure less than 8 mm Hg having ANF less than 150 pg/ml. Unlike the patients with cardiomyopathy (with or without myocarditis), cardiac transplant recipients displayed no correlation between ANF level and either pulmonary arterial wedge pressure (p = 0.50) or right atrial pressure (p = 0.29) despite similarly elevated ANF concentrations (mean +/- standard deviation 168 (83) pg/ml in transplant patients versus 185 (114) pg/ml in cardiomyopathy patients). It is concluded that left and right intracardiac pressures are important determinants of circulating ANF level unaffected by inflammation in patients with cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Atrial Function/physiology , Atrial Natriuretic Factor/blood , Cardiomyopathy, Dilated/blood , Heart Transplantation/physiology , Myocarditis/blood , Adult , Cardiomyopathy, Dilated/physiopathology , Female , Humans , Male , Middle Aged , Myocarditis/physiopathology , Pulmonary Wedge Pressure , Radioimmunoassay , Regression Analysis
16.
Inflamm Bowel Dis ; 2(1): 6-10, 1996.
Article in English | MEDLINE | ID: mdl-23282450

ABSTRACT

: Patients with ulcerative colitis are at increased risk for colorectal adenocarcinoma compared with the general population. Although surveillance for colorectal malignancy and dysplasia (a premalignant lesion) has been recommended, a benefit in reducing mortality from colorectal cancer via surveillance or prophylactic colectomy is still being debated. We reviewed the outcome of 40 consecutive patients with ulcerative colitis with colorectal adenocarcinoma diagnosed between 1956 and 1991 at The Johns Hopkins Hospital. The diagnosis of ulcerative colitis and the tumor, node, metastasis (TNM) stage of colorectal cancer were obtained from clinicopathologic records. Follow-up information was complete for all patients. Patients were divided into two groups: 18 asymptomatic patients who had colorectal cancer detected by colonoscopy, biopsies for dysplasia, or barium enema, or had undergone "prophylactic" colectomy as part of a colorectal cancer-prevention strategy (asymptomatic group), whereas 22 patients did not undergo cancer-prevention testing or prophylactic surgery and had symptoms of colorectal cancer (symptomatic group). Colorectal cancer was diagnosed at a statistically significantly earlier cancer stage in the asymptomatic group [12 (67%) of 18 at stage I or II] compared with those in the symptomatic group [two (9%) of 22 at stage I or II] (Wilcoxon test, p < 0.01). Colorectal cancer 5-year survival in the asymptomatic group was 89% [confidence limit (CL), 6197%] and in the symptomatic group, 19% (CL, 6-39%). Patients with ulcerative colitis and asymptomatic colorectal cancer detected as part of a prevention strategy had malignancies that were less invasive and showed greatly increased survival compared with patients with symptomatic colorectal cancer.

17.
Hum Pathol ; 27(2): 119-24, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8617452

ABSTRACT

Although several morphological and molecular genetic studies have implicated various grades of pancreatic duct hyperplasia as precursor lesions to infiltrating pancreatic adenocarcinoma, the identity of preinvasive pancreatic neoplasms remains controversial. In the present study, the authors examined the expression of the epidermal growth factor receptor homologue, HER-2/neu (c-erbB-2), in pancreatic duct lesions adjacent to infiltrating pancreas cancers in a series of 19 cases of pancreatic duct adenocarcinoma. HER-2/neu expression was examined because it has been identified in a proportion of infiltrating pancreas cancers and because it may provide early neoplasms with a growth advantage over adjacent nonneoplastic epithelium. In normal pancreatic ducts and ductules, HER-2/neu expression was absent in all but one case. By contrast, HER-2/neu was expressed in 82% (P = .008 vs normal ) of ducts with flat mucinous hyperplasia, 86% (P = .03 vs normal) of ducts with papillary mucinous hyperplasia without atypia, 92% (P = .001 vs normal) of ducts with atypical papillary mucinous hyperplasia, and all specimens with carcinoma in situ. HER-2/neu expression was observed in 69% (P = .002 vs normal) of the moderately differentiated infiltrating carcinomas and none of the poorly differentiated infiltrating carcinomas. These data establish HER-2/neu as a potential mediator of growth factor-related signal transduction in pancreatic duct lesions, and provide additional support for the hypothesis that lesions formerly regarded as various grades of hyperplasia instead may represent intraepithelial neoplasms with the potential for subsequent invasion and metastasis.


Subject(s)
Adenocarcinoma/chemistry , Carcinoma in Situ/chemistry , Pancreatic Neoplasms/chemistry , Receptor, ErbB-2/analysis , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Carcinoma in Situ/pathology , Humans , Immunohistochemistry , Middle Aged , Pancreatic Ducts/chemistry , Pancreatic Ducts/pathology , Pancreatic Neoplasms/pathology , Signal Transduction
18.
Bone Marrow Transplant ; 12(3): 273-82, 1993 Sep.
Article in English | MEDLINE | ID: mdl-8241987

ABSTRACT

To assess the efficacy of immune globulin in preventing CMV infection, interstitial pneumonia, GVHD and death after BMT, we reviewed and synthesized data from 12 published studies (with 1282 patients) in which immune globulin was used prophylactically in BMT patients, controls were included and clinical outcomes were assessed. Data synthesis indicates that immune globulin significantly reduces fatal CMV infection (odds ratio (OR) 0.47, 95% confidence interval (CI) 0.23-0.99), CMV pneumonia (OR 0.61, CI 0.42-0.89), non-CMV interstitial pneumonia (OR 0.57, CI 0.35-0.95) and total mortality (OR 0.74, CI 0.55-0.99). The reduction in acute GVHD was not quite significant (OR CI 0.45-1.02). Complications decrease with both hyperimmune and conventional immune globulin. For CMV-negative transplant recipients, immune globulin decreases symptomatic CMV infection (OR 0.55, CI 0.31-0.94) and interstitial pneumonia (OR 0.34, CI 0.15-0.77). For CMV-positive recipients, immune globulin prevents interstitial pneumonia (OR 0.45, CI 0.26-0.80) but not symptomatic CMV infection (CI 0.41-2.80). We conclude that immune globulin is efficacious in preventing major complications of BMT in both CMV-negative and CMV-positive recipients.


Subject(s)
Bone Marrow Transplantation , Cytomegalovirus Infections/prevention & control , Graft vs Host Disease/prevention & control , Immunoglobulins/therapeutic use , Lung Diseases, Interstitial/prevention & control , Adult , Bone Marrow Transplantation/adverse effects , Bone Marrow Transplantation/mortality , Child , Cytomegalovirus Infections/mortality , Epidemiologic Methods , Evaluation Studies as Topic , Female , Graft vs Host Disease/mortality , Humans , Immunoglobulins, Intravenous/therapeutic use , Lung Diseases, Interstitial/mortality , Male , Odds Ratio , Risk , Treatment Outcome
19.
Am J Clin Pathol ; 101(6): 684-8, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8209852

ABSTRACT

Mutations in the p53 tumor suppressor gene are frequently identified in human neoplasms. These mutations may be associated with stabilization and, therefore, with overexpression of the p53 protein product as determined by immunohistochemical staining. Using a new antigen retrieval method and a polyclonal antibody to p53 (CM-1), the authors examined 48 formalin-fixed paraffin-embedded adenocarcinomas of the pancreas for overexpression of the p53 gene product. These 48 carcinomas were obtained from a series of patients with well-documented clinical histories and extensive follow-up. The carcinomas had been analyzed previously for K-ras gene mutations, tumor ploidy, and tumor proliferating index. Specific diffuse nuclear staining for the p53 protein was identified in 19 of the 48 (40%) infiltrating carcinomas examined. Focal or negative staining was seen in the remaining 29 cases (60%). In addition, 17 of the neoplasms contained synchronous in situ carcinomas; two (12%) of these displayed diffuse nuclear staining for the p53 protein. Overexpression of p53 was associated with aneuploidy (P = .05), which had been a poor prognosticator in this series of adenocarcinomas of the pancreas. Although overexpression of p53 appeared to be associated with poor prognosis (hazard ratio, 1.8; P = .07), this was not statistically significant. Overexpression of p53 was not significantly associated with K-ras oncogene mutations or tumor proliferating index. The authors conclude that overexpression of the p53 protein occurs frequently in invasive adenocarcinomas of the pancreas and in some in situ carcinomas, as well.


Subject(s)
Adenocarcinoma/metabolism , Pancreatic Neoplasms/metabolism , Tumor Suppressor Protein p53/metabolism , Adenocarcinoma/pathology , Adult , Aged , Carcinoma in Situ/metabolism , Carcinoma in Situ/pathology , Cell Nucleus/metabolism , Female , Humans , Immunohistochemistry , Male , Middle Aged , Neoplasms, Multiple Primary , Pancreatic Neoplasms/mortality , Pancreatic Neoplasms/pathology , Prognosis , Survival Analysis
20.
J Clin Pathol ; 55(5): 340-5, 2002 May.
Article in English | MEDLINE | ID: mdl-11986336

ABSTRACT

BACKGROUND: Peptic ulcer surgery may carry an increased risk for pancreatic cancer development. Molecular analysis of K-ras codon 12, frequently mutated in conventional pancreatic cancers, might provide insight into the aetiological mechanisms. METHODS: The relative risk of pancreatic cancer was computed by multivariate and person-year analysis in a cohort of 2633 patients who had undergone gastrectomy. Lung cancer risk was analysed as an indirect means of assessing smoking behaviour. K-ras codon 12 mutational analysis was performed on 15 postgastrectomy pancreatic cancers. RESULTS: There was an overall increased risk of pancreatic carcinoma of 1.8 (95% confidence interval, 1.3 to 2.6) five to 59 years postoperatively, which gradually increased to 3.6 at 35 years or more after surgery (chi(2) test for trend, p < 0.05). Multivariate analysis indicated that parameters other than postoperative interval did not influence the risk. Lung cancer risk was significantly increased after surgery, but no time trend was observed. The spectrum and prevalence of K-ras codon 12 mutations were comparable to conventional pancreatic cancer. CONCLUSIONS: Remote partial gastrectomy is associated with an increased risk of pancreatic cancer. Postgastrectomy and non-postgastrectomy pancreatic cancers may share similar aetiological factors, such as smoking. However, the neoplastic process in patients who have undergone gastrectomy appears to be accelerated by factors related to the surgery itself.


Subject(s)
Pancreatic Neoplasms/etiology , Peptic Ulcer/surgery , Postoperative Complications/etiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Cohort Studies , Duodenal Ulcer/surgery , Female , Genes, ras , Humans , Male , Middle Aged , Multivariate Analysis , Mutation/genetics , Netherlands/epidemiology , Pancreatic Neoplasms/mortality , Postoperative Complications/mortality , Postoperative Period , Risk Assessment , Risk Factors , Stomach Ulcer/surgery
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