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Dive into the research topics where Robert L. Becker is active.

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Featured researches published by Robert L. Becker.


Hepatology | 2007

Progression of fibrosis in advanced chronic hepatitis C: Evaluation by morphometric image analysis

Zachary D. Goodman; Robert L. Becker; Paul J. Pockros; Nezam H. Afdhal

Fibrosis progression in chronic liver disease has usually been evaluated by liver biopsy using insensitive semiquantitative numerical scores. An alternative to this is to measure fibrous tissue quantitatively using morphometric image analysis. The aim of this study was to quantify fibrosis progression in a cohort of patients with treatment‐refractory chronic hepatitis C enrolled in a placebo‐controlled clinical trial of interferon gamma‐1b (IFN‐γ 1b) for the treatment of advanced hepatic fibrosis. We used morphometry to quantify the amount of fibrous tissue in liver biopsies performed at baseline and after 48 weeks in 245 patients who had paired unfragmented, adequate‐sized specimens and correlated the results with clinical and laboratory parameters. Eighty‐seven patients were treated with placebo and 158 with IFN‐γ 1b. No effect of the drug on fibrosis was found in the trial, and so data from all 245 patients were combined for analysis. At baseline, 78% had cirrhosis; 22%, bridging fibrosis. The mean morphometrically determined collagen content increased by 58% between baseline and 48 weeks. There were statistically significant but weak correlations of fibrosis with platelet count, albumin, bilirubin, INR, and hyaluronic acid; however, changes in these did not correlate with or predict changes in fibrosis in the liver biopsy. Conclusion: In advanced chronic hepatitis C, fibrosis increases at a rapid pace that can only be detected by morphometry. This technique can be used in future therapeutic trials of agents to inhibit fibrosis progression. (HEPATOLOGY 2007;45:886–894.)


The Journal of Urology | 1993

Flow Cytometric and Quantitative Histological Parameters to Predict Occult Disease in Clinical Stage I Nonseminomatous Testicular Germ Cell Tumors

Judd W. Moul; John P. Foley; Charles L. Hitchcock; William F. McCarthy; Isabell A. Sesterhenn; Robert L. Becker; Joe L. Griffin

The goal of this study was to determine if deoxyribonucleic acid (DNA) flow cytometric and quantitative histological parameters could predict occult metastases in clinical stage I nonseminomatous testicular cancer. Archival paraffin primary tumor tissue was available from 36 clinical stage I nonseminomatous germ cell testicular cancer patients who all had retroperitoneal lymphadenectomy and followup defining 2 groups: pathological stage I (23) and occult pathological stage II (13). Archival blocks were microdissected and individual histological components were subjected to flow cytometry. In addition, the primary histology was reevaluated for vascular invasion and per cent composition of histological components of embryonal carcinoma and other histologies. For flow cytometry parameters, no tumor was uniformly diploid, and the DNA index and per cent S phase cells were not useful in differentiating stages. Although mean per cent S phase for the aneuploid cell population and proliferative index were significantly greater for stage II cases by univariate logistic regression analysis, they are approximately 70% accurate in predicting occult disease as single tests and were not significant by multivariate analysis. The calculation of per cent embryonal carcinoma was also significantly greater in stage II cancer by univariate logistic regression testing and remained significant by multivariate analysis. Vascular invasion was marginally predictive of occult disease but was also not significant by multivariate analysis. Calculating the percentage of embryonal carcinoma of a primary testicular tumor may be a useful method to assess clinical stage I cancer patients for risk of occult disease. A larger study is needed to confirm the importance of per cent embryonal carcinoma and to clarify further if flow cytometry in combination is useful.


Human Pathology | 1989

A comparative morphometric and cytophotometric study of endometrial hyperplasia, atypical hyperplasia, and endometrial carcinoma

Henry J. Norris; Robert L. Becker; Ulrika V. Mikel

The DNA content and nuclear measurements of five groups of endometrial proliferations--proliferative endometrium (PE), simple hyperplasia (SH), atypical hyperplasia (AH), well-differentiated carcinoma (WDC), and poorly differentiated carcinoma (PDC)--were compared using 14 descriptors in a stepwise discriminant analysis. Classification using the discriminant rules agreed with the pathologic interpretation for 78% of the specimens. All PEs were assigned to the correct group, and 97% of benign endometria and carcinomas were correctly classified as benign or malignant. Only two of 39 hyperplasias (5%) were misclassified as malignant, and only one of 36 carcinomas was classified as benign. In the difficult distinction between AH and WDC, using all descriptors for the five groups, only 68% of the AH and 60% of the WDC classifications were in agreement with the pathologist of record. However, when discriminant rules addressing only AH and WDC were used, 37 of 39 AHs and WDCs were in concordance. This suggests that a morphometric distinction between AH and WDC is feasible.


Acta Cytologica | 1997

Differential Diagnosis of Hürthle Cell Neoplasms on Fine Needle Aspirates

Stefan E. Pambuccian; Robert L. Becker; Syed Z. Ali; Kay Savik; Dorothy L. Rosenthal

OBJECTIVE To determine the value of computerized interactive morphometry in the preoperative prediction of malignancy in fine needle aspirates of Hürthle cell neoplasms. STUDY DESIGN Alcohol-fixed, Papanicolaou-stained fine needle aspiration smears of histologically proven Hürthle cell adenomas (HCA) (n = 10) and Hürthle cell carcinomas (HCC) (n = 9) were studied by interactive computerized morphometry. The measured features included the areas, perimeters and shape factors of individual cells, nuclei and nucleoli; the nucleocytoplasmic and nucleolonuclear ratios; and the eccentricities of nuclei and nucleoli. RESULTS Only nucleolar features showed statistically significant differences between HCA and HCC. These features were the nucleolar area and its standard deviation, the nucleolar form factor and circularity, and the nucleolonuclear ratio. The most effective, albeit imperfect, discrimination was achieved by the nucleolar form factor. CONCLUSION Nucleolar features, such as size, variation in size and roundness, may be more effective than cellular or nuclear features in differentiating between HCA and HCC in fine needle aspiration smears.


Human Pathology | 1991

DNA Analysis of cardiac myxomas: Flow cytometry and image analysis

Jeffrey D. Seidman; Jules J. Berman; Charles L. Hitchcock; Robert L. Becker; Wolfgang J. Mergner; G. William Moore; Renu Virmani; Robert A. Yetter

Cardiac myxoma is the most common primary tumor of heart, but there is a longstanding controversy over whether it is a true neoplasm or a reactive lesion. We analyzed 24 cardiac myxomas from 22 patients: 22 by DNA flow cytometry and five by image analysis. Two myxomas were aneuploid; one of those analyzed by flow cytometry, and the other by image analysis. Proliferative fractions (S + G2/M) were high in three tumors from patients with multiple myxomas (mean, 15.9%; SD, 4.0%) as compared with 12 solitary uncomplicated myxomas (mean, 7.7%; SD, 6.0%). S-phase and proliferative fractions were low in embolic, recurrent, and solitary myxomas. The presence of aneuploidy in some myxomas supports a neoplastic origin for this tumor.


Pathology | 1994

Computerized nuclear morphometry and survival in renal cell carcinoma: comparison with other prognostic indicators

Brett Delahunt; Robert L. Becker; Peter Bethwaite; Jorge L. Ribas

&NA; Morphometric nuclear parameters were compared with patient survival for a series of 174 renal cell carcinomas (RCC) collected over a 30 yr period. Stepdown regression showed long diameter, average feret diameter, form factor and the ratio of average feret diameter to equivalent diameter to be significantly associated with survival. Nuclear area, nuclear perimeter, equivalent diameter, ratio of long diameter to average feret diameter and coefficients of variation of nuclear area and nuclear perimeter were not significantly correlated with survival. All parameters were correlated with a 3 division nuclear grading classification using analysis of variance. Multivariate analysis showed nuclear form factor, tumor stage, silver staining nucleolar organizer region numbers and proliferating cell nuclear antigen expression to be independently associated with survival. The results of this study indicate that form factor is the most discriminate morphometric parameter for RCC, providing survival data additional to that derived from tumor staging and from markers of tumor proliferation.


Cancer | 1992

Prediction of prognosis in untreated stage A2 prostatic carcinoma

James L. Mohler; Alan W. Partin; Jonathan I. Epstein; Robert L. Becker; Ulrika V. Mikel; Isabell A. Sesterhenn; F. Kash Mostofi; Donald F. Gleason; Yousuf Sharief; Donald S. Coffey


Cancer Genetics and Cytogenetics | 2006

Correlation of comparative genomic hybridization results of 100 archival uveal melanomas with patient survival

Jason S. White; Ian W. McLean; Robert L. Becker; Alison E. Director-Myska; J. Nath


Cancer | 1997

Uveal melanoma : The importance of large nucleoli in predicting patient outcome-an automated image analysis study

Ian W. McLean; Maria-Elena Sibug; Robert L. Becker; Jeff B. McCurdy


Cancer Genetics and Cytogenetics | 2006

Molecular cytogenetic evaluation of 10 uveal melanoma cell lines

Jason S. White; Robert L. Becker; Ian W. McLean; Alison E. Director-Myska; J. Nath

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Ian W. McLean

Armed Forces Institute of Pathology

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Charles L. Hitchcock

Armed Forces Institute of Pathology

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Jason S. White

Armed Forces Institute of Pathology

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Ulrika V. Mikel

Armed Forces Institute of Pathology

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Zachary D. Goodman

Armed Forces Institute of Pathology

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Bungo Furusato

Uniformed Services University of the Health Sciences

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David G. McLeod

Uniformed Services University of the Health Sciences

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J. Nath

West Virginia University

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William F. McCarthy

Uniformed Services University of the Health Sciences

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A.E. Director-Myska

Armed Forces Institute of Pathology

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