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Dive into the research topics where Robert A. Ambros is active.

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Featured researches published by Robert A. Ambros.


Human Pathology | 1995

Endometrial intraepithelial carcinoma: a distinctive lesion specifically associated with tumors displaying serous differentiation.

Robert A. Ambros; Mark E. Sherman; Christopher M Zahn; Pincas Bitterman; Robert J. Kurman

Endometrial intraepithelial carcinoma (EIC) is a recently described lesion characterized by replacement of endometrial surface epithelium or glands by malignant cells resembling high-grade invasive endometrial carcinoma. EIC has been identified in a high proportion of uteri containing serous carcinoma, but its association with other endometrial tumors is unknown. To determine the strength and specificity of the association of EIC with tumors displaying serous differentiation, the appearance of the endometrium in 38 uteri with serous carcinoma, 113 with endometrioid carcinoma, and 34 with malignant mixed mesodermal tumor (MMMT) were compared. EIC was present in 34 (98%) uteri with serous carcinoma compared with 7 (6%) uteri removed for endometrioid carcinoma (P = .0001). Hyperplasia without atypia was found in only 2 (5%) of 38 serous carcinomas compared with 38 (34%) of 113 endometrioid carcinomas. Similarly, atypical hyperplasia was not found in any uterus with serous carcinoma, but was present in 14 (12%) uteri with endometrioid carcinoma (P = .02). The endometrium was inactive or atrophic in 29 (76%) patients with serous carcinoma compared with 33 (29%) with endometrioid carcinoma (P = .0001). EIC was found in five (56%) of nine MMMTs with a serous epithelial component (serous-MMMT) compared with one (4%) of 25 MMMTs woth an endometrioid epithelial component (endometrioid-MMMT). As with endometrioid and serous carcinomas, hyperplasia with and without atypia was more common with endometrioid-MMMTs as compared with serous-MMMTs. Hyperplasia was found in 25 (100%) and atypical hyperplasia in 8 (32%) of 25 endometrioid-MMMTs, but in none of the nine serous-MMMTs. This study shows that EIC is frequently and specifically associated with uterine tumors displaying serous differentiation. The findings suggest that EIC represents a form of intraepithelial tumor growth characteristic of serous carcinoma and serous MMMT and that EIC is the likely precursor of these neoplasms. In addition, the findings provide further evidence supporting the view that MMMTs represent variants of carcinoma not sarcoma.


Human Pathology | 1997

HER-2/neu gene amplification status in prostate cancer by fluorescence in situ hybridization

Jeffrey S. Ross; Christine E. Sheehan; Alida Hayner-Buchan; Robert A. Ambros; Bhaskar Kallakury; Ronald P. Kaufman; Hugh A.G. Fisher; Patrick J. Muraca

HER-2/neu expression has been established as a prognostic factor in breast and other cancers. In prostate cancer (PC), a similar predictive role has been hindered by variable immunohistochemical (IHC) results. The authors studied DNA amplification of the HER-2/neu gene on 4-microm sections obtained from 62 formalin-fixed, paraffin-embedded PCs by fluorescence in situ hybridization (FISH). The results were compared with HER-2/neu protein expression as determined by IHC and correlated by logistic regression analysis with Gleason tumor grade, DNA ploidy, serum prostate specific antigen (PSA), and pathological stage. The HER-2/neu gene was localized using the Oncor (Gaithersburg, MD) digoxigenin-labeled unique sequence probe. Amplified PCs had at least 20 malignant cells, with 5 or more copies of the sequence. Amplification of HER-2/neu correlated with Gleason score (P = .0001). The mean Gleason score of unamplified tumors was 5.7 and that of amplified tumors was 7.5. Nondiploid tumors had a significantly greater rate of HER-2/neu amplification compared with diploid tumors (P = .0003). Of the 62 cases evaluated by IHC and FISH, 18 cases (29%) were overexpressed by IHC, and 27 cases (44%) were amplified by FISH. A trend for similar HER-2/neu status in each PC by the two methods did not reach statistical significance (P = .23). HER-2/neu amplification by FISH was associated with advanced pathological stage; however, this relationship reached only near-statistical significance (P = .06). There was no correlation of HER-2/neu amplification by FISH with patient age or preoperative serum PSA levels. The authors conclude that HER-2/neu gene amplification status can be determined by FISH on archival prostate cancer specimens, significantly correlates with high tumor grade and nondiploid DNA content, and is more frequently encountered in tumors with advanced pathological stage. Also, FISH is more sensitive than IHC for detection of abnormalities in the HER-2/neu gene, and further studies should be undertaken to determine whether a FISH-based HER-2/neu detection method may prove of importance in the prediction of prognosis and planning of therapy in prostate cancer patients.


Cancer | 1994

Observations on tumor and metastatic suppressor gene status in endometrial carcinoma with particular emphasis on p53

Robert A. Ambros; Paul A. Vigna; James Figge; Bhaskar Kallakury; Anthony Mastrangelo; Allison Y. Eastman; John H. Malfetano; Helen L. Figge; Jeffrey S. Ross

Background. Genetic changes in the development of endometrial carcinoma have not been characterized, and little is known of tumor or metastatic suppressor gene status in these malignancies. The current study on endometrioid carcinoma was undertaken to examine the status of two tumor suppressor genes that frequently have been found to be altered in human malignancies (the p53 gene and the retinoblastoma [Rb] gene) and to examine the status of the candidate metastatic suppressor gene, nm23‐H1.


Cancer | 1998

Prognostic significance of tumor necrosis factors and their receptors in nonsmall cell lung carcinoma

Tien-Anh Tran; Bhaskar Kallakury; Robert A. Ambros; Jeffrey S. Ross

In vitro studies have shown an antiproliferative effect of tumor necrosis factor (TNF) against various nonsmall cell lung carcinoma (NSCLC) cell lines. However, clinical trials of combined interleukin‐2 and TNF‐α in patients with advanced NSCLC have demonstrated both conflicting and disappointing results.


The American Journal of Surgical Pathology | 1999

Needle biopsy DNA ploidy status predicts grade shifting in prostate cancer.

Jeffrey S. Ross; Christine E. Sheehan; Robert A. Ambros; Tipu Nazeer; Timothy A. Jennings; Ronald P. Kaufman; Hugh A.G. Fisher; Matthew D. Rifkin; Bhaskar Kallakury

DNA ploidy analysis of prostate needle biopsy specimens was performed to determine whether ploidy status could predict tumor grade shifting at radical prostatectomy. The paired needle biopsy and radical prostatectomy specimens from 111 randomly selected men with prostate cancer were obtained from the surgical pathology files of the Albany Medical Center Hospital. The original tumor grades were assigned by a staff of 12 surgical pathologists according to the Gleason system. Tumors with original Gleason scores < or = 6 were classified as low grade, and tumors with scores of > or = 7 were considered high grade. DNA ploidy analysis was performed on the needle biopsy specimens using the CAS 200 image analyzer (Becton Dickinson Immunocytometry Systems, Mountain View, CA, USA) on Feulgen stained 5-microm tissue sections. There were 88 diploid and 23 nondiploid cases. Thirty-eight of 111 (34%) of cases had grade shifting from needle biopsy to radical prostatectomy specimens. Of 89 low-grade needle biopsy cases, 28 (31%) were upgraded at radical prostatectomy. Of 22 high-grade needle biopsy cases, 10 (45%) were downgraded to low grade at radical prostatectomy. Of the 28 low-grade needle biopsy specimens that were upgraded at radical prostatectomy, 19 (68%) featured an aneuploid histogram and 9 (32%) were diploid. Nineteen of 28 (68%) of aneuploid low-grade tumors on needle biopsy became high-grade at radical prostatectomy. Nine of 10 (90%) diploid high-grade tumors at needle biopsy became low-grade at radical prostatectomy. Of the 38 cases in which ploidy and grade were incongruous, 28 (74%) had grade shifting. In a multivariate regression analysis, a high-grade Gleason score on radical prostatectomy specimens correlated significantly with needle biopsy ploidy (p = 0.0001) but not with needle biopsy grade (p = 0.15). The sensitivity of the needle biopsy grade in the detection of high-grade tumors on radical prostatectomy was 30%, and the specificity was 86%. The sensitivity of ploidy status in the prediction of high grade at radical prostatectomy was 78%, and the specificity was 96%. With a prostate-specific antigen (PSA) level of >0.4 ng/ml as the indicator of post-radical prostatectomy disease recurrence on a subset of 106 patients, on univariate analysis, disease recurrence was predicted by needle biopsy ploidy (p = 0.001) and radical prostatectomy grade (p = 0.04) but not by needle biopsy grade (p = 0.39). On multivariate analysis, needle biopsy DNA ploidy status independently predicted disease recurrence (p = 0.002), whereas needle biopsy and prostatectomy grade did not. These results indicate that DNA ploidy analysis of needle biopsy specimens of prostate cancer predicts grade shifting, that it is a more sensitive and specific indicator of final tumor grade at radical prostatectomy than is the original needle biopsy grade, and that ploidy status independently predicts postoperative disease recurrence.


International Journal of Gynecological Pathology | 1998

Cell proliferation-associated proteins in endometrial carcinomas, including papillary serous and endometrioid subtypes

Bhaskar Kallakury; Robert A. Ambros; Alida Hayner-Buchan; Christine E. Sheehan; John H. Malfetano; Jeffrey S. Ross

SummaryCyclin dependent kinases (cdks) and cyclins regulate the progression of cells through the cell cycle and can be overexpressed in human cancers. The purpose of this study was to evaluate the immunohistochemical profile of these proliferation-associated proteins and correlate the results with clinicopathologic parameters of endometrial carcinomas. Archival tissue sections from 91 endometrial carcinomas were immunostained using monoclonal antibodies against p34CDC2 cdk, cyclins A and B1, p120, Ki-67, and PCNA. Immunoreactivity was semiquantitatively assessed and the results correlated with pathologic features and survival. Of the 91 endometrial carcinomas, 74 were endometrioid (17 villoglandular, 57 of usual type) and 17 were papillary serous carcinomas. The positivity rates for the different proteins in papillary serous and endometrioid tumors, respectively, were as follows: p34CDC2 24% and 23%; cyclin A, 71% and 64%; cyclin B1, 24% and 26%; p 120, 47% and 9%; Ki-67, 82% and 64%; and PCNA, 47% and 47%. Only p120 correlated with histologic tumor type with significantly higher expression in both papillary serous and villoglandular endometrioid carcinomas compared to nonvilloglandular endometrioid carcinomas (p = 0.0001). p120 positivity also correlated with advanced tumor stage (p = 0.0001). Ki-67, cyclin A, and PCNA correlated with patient survival in endometrioid carcinomas on univariate analysis (p = 0.01, 0.02, and 0.003, respectively), but, on multi-variate analysis, only tumor grade (p = 0.02) and depth of invasion (p = 0.04) were independent predictors of outcome. In summary, although most of the cell proliferation-associated proteins studied did not appear to be associated with clinicopathologic features of endometrial carcinoma, there was significantly higher expression of pi20 in papillary serous and villoglandular endometrioid carcinomas compared to nonvilloglandular endometrioid carcinomas, suggesting a possible role of pi20 in tumor behavior. In addition, Ki-67, cyclin A, and PCNA expression correlated with survival in endometrioid carcinoma, but only in a univariate analysis.


International Journal of Gynecological Pathology | 2002

Primary peritoneal mullerian adenosarcoma with sarcomatous overgrowth associated with endometriosis: a case report.

Ayse D. Dincer; Patrick Timmins; Donna Pietrocola; Hugh A.G. Fisher; Robert A. Ambros

We report a primary peritoneal mullerian adenosarcoma with sarcomatous overgrowth associated with endometriosis in a 50-year-old female. The tumor formed multiple peritoneal masses occupying the pelvis and subdiaphragmatic space. Histologically, the tumor was composed of benign-appearing mullerian glands surrounded by a sarcomatous stroma. In addition, one perisplenic mass was largely devoid of the epithelial component and was of higher grade than the remaining lesions. Multiple foci of endometriosis were associated with the pelvic masses. To our knowledge, primary peritoneal mullerian adenosarcoma with sarcomatous overgrowth associated with endometriosis has not been previously reported.


American Journal of Obstetrics and Gynecology | 1995

Multivariate survival analysis of clinicopathologic features in surgical stage I endometrioid carcinoma including analysis of HER-2/neu expression

Tipu Nazeer; Fayez Ballouk; John H. Malfetano; Helen L. Figge; Robert A. Ambros

OBJECTIVE We previously described vascular invasion-associated changes, defined as the presence of vascular invasion or perivascular lymphocytic infiltrates, as key prognostic indicators in stage I endometrioid carcinoma. The current study was undertaken to examine the prognostic value of HER-2/neu expression in relation to other factors, including vascular invasion-associated changes, in surgical stage I endometrioid carcinoma. STUDY DESIGN Seventy-one patients with surgical stage I endometrioid carcinoma treated by hysterectomy and followed up were randomly chosen for retrospective analysis of prognostic indicators including standard clincopathologic features, deoxyribonucleic acid ploidy, and HER-2/neu expression. The latter was examined by an objective computerized quantitative immunohistochemical system. RESULTS By univariate analysis many factors were found to correlate with outcome, including age, tumor grade, depth of invasion, ploidy, HER-2/neu expression, and vascular invasion-associated changes. By multivariate analysis only vascular invasion-associated changes, aneuploidy, and HER-2/neu overexpression were found to independently correlate with survival. Stratification of patients on the basis of these three features revealed survival rates of 100%, 92%, and 60% when none, one, and two or three features were present, respectively. CONCLUSION This study suggests that HER-2/neu expression correlated with outcome independent of other factors in endometrial carcinoma and may aid in estimating prognosis. The prognostic value of HER-2/neu overexpression independent of vascular invasion suggests that this factor may operate by increasing the ability of tumor cells to grow at a distal site once vascular invasion occurs.


Human Pathology | 1987

The acquired immunodeficiency syndrome in intravenous drug abusers and patients with a sexual risk: Clinical and postmortem comparisons

Robert A. Ambros; Eun-Young Lee; Leroy R. Sharer; M. Yusuf Khan; Stanley J. Robboy

Clinical and necropsy findings in 13 intravenous drug abusers who died of the acquired immunodeficiency syndrome (AIDS) were reviewed and compared with findings in eight patients who acquired the infection through sexual exposure, the most common mode of transmission in AIDS. No differences were found in lymphocyte counts or duration of survival, despite reports that the degree of immunosuppression in intravenous drug abusers with AIDS differs from that in homosexuals. Neoplasms were found in 25 per cent of patients with sexual risks, but not in any drug abusers (0 per cent). Two opportunistic infections (toxoplasmosis and cytomegalovirus pneumonia and esophagitis) were more common in the intravenous drug abuser group. Although cytomegalovirus has been associated with Kaposis sarcoma, this association was not found in this study. The postmortem findings in both groups were otherwise similar.


International Journal of Gynecological Pathology | 2000

Simple hyperplasia of the endometrium: an evaluation of proliferative activity by Ki-67 immunostaining.

Robert A. Ambros

As endometrial hyperplasia has been characterized over the past 100 years, some investigators have questioned the hyperplastic nature of nonatrophic cystic glands associated with an increase in gland-to-stroma ratio, which is currently considered to represent simple endometrial hyperplasia. In the current study, the proliferative activity of simple endometrial hyperplasia was examined using an antibody to Ki-67 protein, a well-established marker of proliferative activity, and compared with the results of activity in inactive/atrophic endometrium, proliferative endometrium, and other forms of endometrial hyperplasia. In an evaluation of 68 endometrial biopsy specimens showing 110 histologic patterns, the mean Ki-67 index (percentage of Ki-67 positive nuclei) was 2.8% in inactive/atrophic endometrium, 23.2% in proliferative endometrium, 9.8% in simple hyperplasia, 12.7% in complex hyperplasia, and 10% in atypical complex hyperplasia. In simple hyperplasias, the mean Ki-67 index was 3.9% in dilated glands without infolding or outbranching, 14.6% in nondilated glands showing outbranching or slight crowding, and 6.9% in dilated glands with infolding or outbranching. Ki-67 indices for dilated glands were most similar, therefore, to atrophic/inactive endometrium with no statistical significant difference in the percentage of these cells staining between these two groups. In contrast, statistically significant differences were seen in staining between cystic patterns of simple hyperplasia and proliferative endometrium, simple hyperplasia showing outbranching and/or slight crowding but no dilation, complex hyperplasia, and atypical hyperplasia. The findings in the current study suggest that nonatrophic cystic glands with an increase in the gland-to-stroma ratio in the endometrium should not be considered a hyperplastic process and in the absence of other findings such as excessive bleeding or coexistent noncystic simple hyperplasia, treatment with progestin therapy, a widely used practice, is unnecessary. As discussed, the findings also suggest that these cystic forms of simple hyperplasia are precursors of cystic atrophies. Confirmation of these results on a larger population by a different research team appears desirable.

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Jeffrey S. Ross

State University of New York Upstate Medical University

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Martin C. Mihm

Brigham and Women's Hospital

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Tipu Nazeer

Albany Medical College

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