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Dive into the research topics where Bonnie Balzer is active.

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Featured researches published by Bonnie Balzer.


Modern Pathology | 2015

Clinicopathological analysis of endometrial carcinomas harboring somatic POLE exonuclease domain mutations.

Yaser R. Hussein; Britta Weigelt; Douglas A. Levine; J. Kenneth Schoolmeester; Linda N Dao; Bonnie Balzer; Georgia Liles; Beth Y. Karlan; Martin Köbel; Cheng-Han Lee; Robert A. Soslow

The Cancer Genome Atlas described four major genomic groups of endometrial carcinomas, including a POLE ultramutated subtype comprising ∼10% of endometrioid adenocarcinoma, characterized by POLE exonuclease domain mutations, ultrahigh somatic mutation rates, and favorable outcome. Our aim was to examine the morphological and clinicopathological features of ultramutated endometrial carcinomas harboring somatic POLE exonuclease domain mutations. Hematoxylin and eosin slides and pathology reports for 8/17 POLE-mutated endometrial carcinomas described in the Cancer Genome Atlas study were studied; for the remaining cases, virtual whole slide images publicly available at cBioPortal (www.cbioportal.org) were examined. A second cohort of eight POLE mutated endometrial carcinomas from University of Calgary was also studied. Median age was 55 years (range 33–87 years). Nineteen patients presented as stage I, 1 stage II, and 5 stage III. The majority of cases (24 of the 25) demonstrated defining morphological features of endometrioid differentiation. The studied cases were frequently high grade (60%) and rich in tumor-infiltrating lymphocytes and/or peri-tumoral lymphocytes (84%); many tumors showed morphological heterogeneity (52%) and ambiguity (16%). Foci demonstrating severe nuclear atypia led to concern for serous carcinoma in 28% of cases. At the molecular level, the majority of the Cancer Genome Atlas POLE-mutated tumors were microsatellite stable (65%), and TP53 mutations were present in 35% of cases. They also harbored mutations in PTEN (94%), FBXW7 (82%), ARID1A (76%), and PIK3CA (71%). All patients from both cohorts were alive without disease, and none of the patients developed recurrence at the time of follow-up (median 33 months; range 2–102 months). In conclusion, the recognition of ultramutated endometrial carcinomas with POLE exonuclease domain mutation is important given their favorable outcome. Our histopathological review revealed that these tumors are commonly high grade, have obvious lymphocytic infiltrates, and can show ambiguous morphology. As they frequently harbor TP53 mutations, it is important not to misclassify them as serous carcinoma.


Archives of Pathology & Laboratory Medicine | 2010

Protocol for the Examination of Specimens From Patients With Merkel Cell Carcinoma of the Skin

Priya Rao; Bonnie Balzer; Bianca D. Lemos; Nanette J. Liegeois; Jennifer M. McNiff; Paul Nghiem; Victor G. Prieto; M. Timothy Smith; Bruce R. Smoller; Mark R. Wick; David Frishberg

The College of American Pathologists offers these protocols to assist pathologists in providing clinically useful and relevant information when reporting results of surgical specimen examinations. The College regards the reporting elements in the ‘‘Surgical Pathology Cancer Case Summary (Checklist)’’ portion of the protocols as essential elements of the pathology report. However, the manner in which these elements are reported is at the discretion of each specific pathologist, taking into account clinician preferences, institutional policies, and individual practice. The College developed these protocols as an educational tool to assist pathologists in the useful reporting of relevant information. It did not issue the protocols for use in litigation, reimbursement, or other contexts. Nevertheless, the College recognizes that the protocols might be used by hospitals, attorneys, payers, and others. Indeed, effective January 1, 2004, the Commission on Cancer of the American College of Surgeons mandated the use of the checklist elements of the protocols as part of its Cancer Program Standards for Approved Cancer Programs. Therefore, it becomes even more important for pathologists to familiarize themselves with these documents. At the same time, the College cautions that use of the protocols other than for their intended educational purpose may involve additional considerations that are beyond the scope of these documents. PROTOCOL FOR THE EXAMINATION OF SPECIMENS FROM PATIENTS WITH MERKEL CELL CARCINOMA OF THE SKIN This protocol applies to Merkel cell carcinoma of cutaneous surfaces only. The seventh edition TNM staging system for Merkel cell carcinoma of the American Joint Committee on Cancer (AJCC) and the International Union Against Cancer (UICC) is recommended.


Human Pathology | 2009

Do biomaterials cause implant-associated mesenchymal tumors of the breast? Analysis of 8 new cases and review of the literature

Bonnie Balzer; Sharon W. Weiss

Implant-associated mesenchymal tumors (IAMT) of the breast are rare, and most are fibromatoses. There has been no systematic analysis of IAMT to determine their full histologic spectrum, whether there is an association with implant type or rupture, and if evidence supports a causal or fortuitous relationship between tumor and implant. We, therefore, analyzed all mesenchymal tumors associated with breast implants from our soft tissue consultation database spanning a period from 1989 to 2005. Information regarding location, type, and integrity of implant and its temporal relationship to tumor was recorded. Eight IAMT were identified exclusively in female patients (ages 28-64 years; median, 38 years), all of whom presented with a palpable mass. Tumors developed after placement of either a silicone (n = 7) or saline (n = 1) implant (median, 2 years; range, 1.8-10 years), which was usually inserted for cosmetic purposes (n = 7). All tumors arose in or around the capsule of a grossly intact implant, and in one case, the tumor was confined exclusively to the implant capsule. In patients with silicone implants, silicone granulomas were identified within the capsule and associated neoplasm despite the integrity of the implant. Six cases were fibromatoses; one was a pleomorphic undifferentiated sarcoma; and one was a fibrosarcoma. None of the patients with fibromatosis was known to have familial adenomatous polyposis (FAP) or Gardner syndrome, although one had Poland syndrome (aplasia of the thorax). One patient with a sarcoma had received radiation 10 years previously for breast carcinoma. Six patients were treated with local excision, one with a wide excision, and one patient with fibromatosis was treated with medical therapy. Median follow-up was 3.2 years (range, 16-92 months). One of the 5 patients with fibromatosis developed 2 recurrences. Neither of the 2 patients with sarcomas has developed metastasis. No patient has died of disease. We conclude that IAMT comprise 2 distinct groups-fibromatosis and sarcoma. Surgical trauma, perhaps occurring in patients with a predisposition to develop desmoid tumors, could account for fibromatosis in this setting. The causal relationship between implants and sarcomas is difficult to assess given the rarity of these tumors and that some may be radiation induced. However, at present, there is insufficient evidence to claim that they are biomaterial related.


Modern Pathology | 2015

CIC-DUX sarcomas demonstrate frequent MYC amplification and ETS-family transcription factor expression.

Steven C. Smith; Darya Buehler; Eun Young Karen Choi; Jonathan B. McHugh; Brian P. Rubin; Steven D. Billings; Bonnie Balzer; Dafydd G. Thomas; David R. Lucas; John R. Goldblum; Rajiv M. Patel

Recent molecular advances have identified a novel, clinically aggressive subgroup of undifferentiated round cell sarcomas defined molecularly by oncogenic fusion of the gene, CIC, and either DUX4 or its paralog, DUX4L, herein termed CIC-DUX sarcomas. Morphologically, CIC-DUX sarcomas are round cell sarcomas with high-grade nuclear features, including vesicular chromatin and nucleoli, patchy clear cell foci, myxoid change, and necrosis. Here, we studied a cohort of 10 cases, including 6 newly identified cases, 2 with paired metastases. Given our prior observation of trisomy 8 in these tumors, we assayed for amplification and expression of MYC (c-Myc) and representative downstream targets. Trisomy 8 was detected in 5/7 testable cases, with further amplification of MYC locus in 6/7 testable cases and immunohistochemical expression of MYC in 10/10. The canonical MYC transcriptional target, p21, but not MTDH, was differentially expressed compared with Ewing sarcomas. Given prior observation of induction of ETS-family transcription factors by the fusion oncoprotein, we assayed and identified highly prevalent positivity for ERG (9/10) and FLI1 (8/8). These findings are cautionary regarding use of these immunostains in prospective case workup, whereas the prevalent MYC amplification may represent a therapeutically targetable oncogenic pathway in CIC-DUX sarcomas.


American Journal of Dermatopathology | 2015

GATA3 Expression in Normal Skin and in Benign and Malignant Epidermal and Cutaneous Adnexal Neoplasms.

Richard B. Mertens; Mariza de Peralta-Venturina; Bonnie Balzer; David Frishberg

Abstract:Initial investigations reported GATA3 to be a sensitive and relatively specific marker for mammary and urothelial carcinomas. Recently, GATA3 expression has been described in several other epithelial tumors. However, there has been only limited investigation of GATA3 expression in cutaneous epithelial tumors. The objective of this study was to examine the immunohistochemical expression of GATA3 in a wide variety of cutaneous epithelial neoplasms. GATA3 expression was evaluated in 99 benign and 63 malignant cutaneous epithelial tumors. GATA3 was consistently and usually strongly expressed in clear cell acanthoma, trichofolliculoma, trichoepithelioma, trichilemmoma, sebaceous adenoma, sebaceoma, apocrine hidrocystoma, apocrine tubular papillary adenoma, hidradenoma papilliferum, and syringocystadenoma papilliferum. Hidradenomas exhibited variable positive staining. Most poromas, syringomas, chondroid syringomas, cylindromas, and spiradenomas were negative or only focally and weakly positive. Focal staining was present in all pilomatrixomas. Thirteen of 14 basal cell carcinomas, 21 of 24 squamous carcinomas, and all 6 sebaceous carcinomas exhibited positive staining. The 1 apocrine carcinoma, both mucinous carcinomas, and 2 of 3 microcystic adnexal carcinomas also exhibited positive staining, whereas the 1 eccrine porocarcinoma and the 1 adenoid cystic carcinoma were negative. One of 11 Merkel cell carcinomas exhibited focal weak staining. Our findings demonstrate that GATA3 is expressed in a wide variety of benign and malignant cutaneous epithelial neoplasms. In addition to carcinomas of breast and urothelial origin and other more recently described GATA3-positive tumors, the differential diagnosis of a metastatic tumor of unknown primary origin that expresses GATA3 should also include a carcinoma of cutaneous epithelial origin.


The American Journal of Surgical Pathology | 2013

Utility of a triple antibody cocktail intraurothelial neoplasm-3 (IUN-3-CK20/CD44s/p53) and α-methylacyl-CoA racemase (AMACR) in the distinction of urothelial carcinoma in situ (CIS) and reactive urothelial atypia.

Manju Aron; Daniel Luthringer; Jesse K. McKenney; Donna E. Hansel; Danielle E. Westfall; Rugvedita Parakh; Sambit K. Mohanty; Bonnie Balzer; Mahul B. Amin

Urothelial carcinoma in situ (CIS) is a prognostically and therapeutically significant lesion with considerable morphologic overlap with reactive conditions especially in the setting of prior therapy. Various markers including CK20, CD44s, and p53 have been used as an adjunct in making this distinction; however, the utility of these markers in the posttreatment scenario is not fully established. &agr;-Methylacyl-CoA racemase (AMACR) is a tumor-associated marker that is expressed in a subset of high-grade urothelial carcinomas but has not been studied in CIS. This study was undertaken to evaluate the immunoreactivity of CK20, CD44s, and p53 as a triple antibody cocktail intraurothelial neoplasm-3 (IUN-3) in distinguishing CIS from its mimics and to compare its utility with AMACR in the diagnosis of CIS. A total of 135 specimens (7 benign ureters and 128 bladder biopsies—28 reactive, 33 posttherapy reactive, 43 CIS, 24 CIS posttherapy) were included in this study. Immunostaining for p53 (brown, nuclear), CD44s (brown, membranous), and CK20 (red, cytoplasmic and membranous) was performed as a cocktail, and the staining pattern was further classified as: malignant (full-thickness CK20 and/or full-thickness p53 with CD44s negativity), reactive/benign (CK20 limited to the umbrella cell layer, p53 negative, and CD44s positivity ranging from basal to full thickness), and indeterminate (CK20 and p53 positive but not full thickness and/or CD44s positive). AMACR staining was performed in 50 cases. Cytoplasmic staining for AMACR was graded as negative (absent to weak focal staining [<5% cells]) and positive (≥5%). The “IUN-3 malignant” pattern was observed in 84% of cases of CIS without a history of prior therapy and in 71% of the cases of CIS with a history of prior therapy. Cases with posttherapy reactive atypia showed an “IUN-3 reactive” pattern in 84% cases and “IUN-3 indeterminate” pattern in 16% of the cases; the IUN-3 malignant pattern was not identified in any of the cases. Benign and reactive urothelium (with and without a history of therapy) showed an IUN-3 reactive pattern and negative AMACR staining in all the cases (100%). AMACR positivity was observed in 78% of nontreated CIS cases and 50% of CIS posttherapy cases. In these cases, the IUN-3 cocktail showed an IUN-3 malignant pattern in 83% of untreated CIS cases and 88% of CIS posttherapy cases. AMACR positivity is a potentially useful marker of CIS. However, the IUN-3 malignant pattern is a more reliable indicator of CIS compared with AMACR, especially in the posttreatment setting. The simultaneous evaluation of all 3 markers (p53, CD44s, and CK20) in a single slide in the form of a cocktail is advantageous, especially in small biopsy specimens.


Gynecologic Oncology | 2012

Predictors of resolution of complex atypical hyperplasia or grade 1 endometrial adenocarcinoma in premenopausal women treated with progestin therapy

Kristine R. Penner; Oliver Dorigo; Chisa Aoyama; Nora Ostrzega; Bonnie Balzer; Jianyu Rao; C. Walsh; Ilana Cass; Christine H. Holschneider

OBJECTIVE To identify clinical and pathologic predictors of response to progestin treatment in premenopausal women with complex atypical hyperplasia (CAH) and Grade 1 endometrial adenocarcinoma (Grade 1 EA). METHODS Forty premenopausal patients with Grade 1 EA or CAH who underwent progestin therapy for a minimum of 8 weeks were retrospectively identified. Patient characteristics and histopathologic features of pretreatment and first follow-up endometrial specimens were evaluated as predictors of resolution, defined as absence of hyperplasia or carcinoma. RESULTS Kaplan-Meier analysis indicated 63% resolution at 18 months of follow-up. Multivariate classification analysis showed that resolution rates were higher in individuals with a low pre-treatment qualitative abnormal architecture score and a BMI <35 (Standardized Resolution Ratio (SRR)=1.48, p=0.03). The diagnosis of benign endometrium or simple hyperplasia on the first follow-up specimen was highly predictive of resolution (SRR=2.25, p=0.002). Resolution rates were lower among subjects with a high pre-treatment qualitative abnormal architecture score (SRR=0.37, p<0.03) and lowest in subjects whose first follow-up specimen showed persistent complexity, atypia, or carcinoma with adjacent stromal decidualization (SRR=0.24, p=0.002). CONCLUSIONS Clinical and pathologic parameters can predict response to progestin therapy in premenopausal women with CAH and Grade 1 EA. A low likelihood of resolution is predicted by an unfavorable pre-treatment architectural score and lack of pathological response in the first specimen, despite adjacent stromal decidualization.


American Journal of Clinical Pathology | 2009

Expression of Hepatocyte Antigen in Small Intestinal Epithelium and Adenocarcinoma

Mylinh T. Mac; Fai Chung; Fan Lin; Pei Hui; Bonnie Balzer; Hanlin L. Wang

Hepatocyte antigen is recognized by antibody Hep Par 1, a widely used diagnostic immunomarker for hepatocellular carcinoma and tumors with hepatoid differentiation. Hepatocyte antigen expression has also been detected in nonneoplastic small intestinal epithelium, but expression in small intestinal adenocarcinoma has not been well investigated. We immunohistochemically examined 39 nonampullary small intestinal adenocarcinomas for hepatocyte antigen expression; 34 cases contained normal-appearing nonneoplastic small intestinal mucosa on the same tissue sections. In 30 cases (88%), the nonneoplastic mucosa exhibited granular cytoplasmic Hep Par 1 staining exclusively in the epithelium. Only 9 small intestinal adenocarcinomas (23%) showed focal positive cytoplasmic staining. Nonneoplastic colonic epithelium was negative for Hep Par 1. In 31 colorectal adenocarcinomas, 3 (10%) showed positive staining for Hep Par 1 (1 diffuse, 2 focal), a frequency not different from that for small intestinal adenocarcinomas (P = .2467). Tumors expressing hepatocyte antigen did not exhibit evidence of hepatoid differentiation and were histologically indistinguishable from hepatocyte antigen-negative tumors. Hepatocyte antigen immunoreactivity is selectively expressed in nonneoplastic small intestinal enterocytes but not in colonocytes, suggesting a potential physiologic role in intestinal biology. Whether the loss of antigen expression in a large number of small intestinal adenocarcinomas serves a role in small intestinal tumorigenesis remains to be investigated.


Journal of Gastroenterology and Hepatology | 2010

Interobserver and intraobserver variability in evaluating vascular invasion in hepatocellular carcinoma.

Lifang Fan; Mylinh T. Mac; David Frishberg; Xuemo Fan; Deepti Dhall; Bonnie Balzer; Stephen A. Geller; Hanlin L. Wang

Background and Aim:  Hepatocellular carcinoma (HCC) is unique in that the presence of vascular invasion significantly changes tumor stage. Even though searching for vascular invasion is a common practice in surgical pathology, there appears to be a great variation among pathologists in its recognition. This study was designed to assess whether HCC could be accurately staged using vascular invasion as a staging parameter.


Diagnostic Pathology | 2014

Effects of tissue decalcification on the quantification of breast cancer biomarkers by digital image analysis

Arkadiusz Gertych; Sonia Mohan; Shawn Maclary; Sambit K. Mohanty; Kolja Wawrowsky; James Mirocha; Bonnie Balzer; Beatrice Knudsen

BackgroundRecent technical advances in digital image capture and analysis greatly improve the measurement of protein expression in tissues. Breast cancer biomarkers provide a unique opportunity to utilize digital image analysis to evaluate sources of variability that are caused by the tissue preparation, in particular the decalcification treatment associated with the analysis of bone metastatic breast cancer, and to develop methods for comparison of digital data and categorical scores rendered by pathologists.MethodsTissues were prospectively decalcified for up to 24 hours and stained by immunohistochemistry (IHC) for ER, PR, Ki-67 and p53. HER2 positive breast cancer sections were retrieved from the pathology archives, and annotated with the categorical HER2 expression scores from the pathology reports. Digital images were captured with Leica and Aperio slide scanners. The conversion of the digital to categorical scores was accomplished with a Gaussian mixture model and tested for accuracy by comparison to clinical scores.ResultsWe observe significant effects of the decalcification treatment on common breast cancer biomarkers that are used in the clinic. ER, PR and p53 staining intensities decreased 15 - 20%, whereas Ki-67 decreased > 90% during the first 6 hrs of treatment and stabilized thereafter. In comparison with the Aperio images, pixel intensities generated by the Leica system are lower. A novel statistical model for conversion of digital to categorical scores provides a systematic approach for conversion of nuclear and membrane stains and demonstrated a high concordance with clinical scores.ConclusionDigital image analysis greatly improves the quantification of protein expression in human tissues. Decalcification affects the accuracy of immunohistochemical staining results and cannot be reversed by image analysis. Measurement data obtained on a continuous scoring scale can be converted to categorical scores for comparison with categorical dataset that are generated by pathologists.Virtual SlidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_213

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David Frishberg

Cedars-Sinai Medical Center

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Xuemo Fan

Cedars-Sinai Medical Center

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Sambit K. Mohanty

Cedars-Sinai Medical Center

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C. Walsh

Cedars-Sinai Medical Center

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Catherine I. Barry

Cedars-Sinai Medical Center

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Hanlin L. Wang

Cedars-Sinai Medical Center

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Ilana Cass

Cedars-Sinai Medical Center

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James Mirocha

Cedars-Sinai Medical Center

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Jinping Lai

Cedars-Sinai Medical Center

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