Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Osvaldo Hernandez is active.

Publication


Featured researches published by Osvaldo Hernandez.


Modern Pathology | 2006

PAX2: a reliable marker for nephrogenic adenoma

Guo-Xia Tong; Jonathan Melamed; Mahesh Mansukhani; Lorenzo Memeo; Osvaldo Hernandez; Fang-Ming Deng; Luis Chiriboga; Jerry Waisman

Nephrogenic adenoma is a rare lesion of the urinary tract. The diagnosis usually is straightforward when characteristic microscopic and clinical findings are present, and the entity is familiar. However, misdiagnosis, in particular of adenocarcinoma of the prostate gland, may occur. Immunohistochemical stains often are needed to make such a distinction, but currently available markers offered only partial help. It recently was demonstrated that nephrogenic adenoma in renal transplant patients originated from the renal tubular epithelium. This newly proved, but long sought information may be helpful in the differential diagnosis of neophrogenic adenoma. In this study, we investigated the expression of a renal transcription factor, PAX2, in 39 nonrenal transplant-related nephrogenic adenomas, 100 adenocarcinomas of the prostate gland, and 47 urothelial carcinomas of the urinary tract. A strong and distinct nuclear staining of PAX2 was found in all 39 cases of nephrogenic adenoma (100%), but not in normal prostate tissue, normal urothelium, adenocarcinomas of the prostate gland, and invasive urothelial carcinomas. Focal CD10 was detected in six of 13 nephrogenic adenomas in the superficial papillary component and in normal prostate epithelium, normal urothelium, lymphocytes, adenocarcinoma of the prostate gland, and urothelial carcinoma. There was no uroplakins detected in nephrogenic adenoma. Therefore, these findings are suggesting that nephrogenic adenoma in nonrenal transplant patients may also arise from the renal epithelium, as did the comparable lesions after transplantation. PAX2 is a specific and sensitive immunohistochemical marker in identification and differential diagnosis of nephrogenic adenoma.


CytoJournal | 2005

Is an increase in CD4/CD8 T-cell ratio in lymph node fine needle aspiration helpful for diagnosing Hodgkin lymphoma? A study of 85 lymph node FNAs with increased CD4/CD8 ratio

Osvaldo Hernandez; Thaira Oweity; Sherif Ibrahim

Background An elevated CD4/CD8 T-cell ratio on flow cytometry (FCM) analysis has been reported in the literature to be associated with Hodgkin lymphoma (HL). The purpose of our study was to determine the diagnostic significance of an elevated CD4/CD8 ratio in lymph node fine needle aspiration (FNA) specimens. Design Between 1996 and 2002, out of 837 lymph node FNAs submitted for flow cytometry analysis, 85 cases showed an elevated CD4/CD8 ratio, defined as greater than or equal to 4, without definitive evidence of a lymphoproliferative disorder. The cytologic diagnoses of these 85 cases were grouped into four categories: reactive, atypical, Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL). Histologic follow-up was available in 17/85 (20%) of the cases. Results 5 of the 64 cases in which FCM and cytology did not reveal evidence of a lymphoproliferative disease had tissue follow-up because of persistent lymphadenopathy and high clinical suspicion. 3/5 (60%) confirmed the diagnosis of reactive lymphadenopathy. The two remaining cases (40%) were positive for lymphoma (1HL, 1NHL). 8/15 cases called atypical on cytology had histologic follow-up. 7/8 (87.5%) cases were positive for lymphoma (3HL, 4NHL). 3/4 cases called HL on cytology had tissue follow-up and all 3 (100%) confirmed the diagnosis of HL. One case diagnosed as NHL on cytology was found to be a diffuse large B-cell lymphoma. In summary, out of 17 cases with histologic follow-up 4/17 (24%) were reactive with CD4/CD8 T-cell ratio of 4.1–29, 7/17 (41%) were HLs with CD4/CD8 T-cell ratio of 5.3 – 11, and 6/17 (35%) were NHLs with CD4/CD8 T-cell ratio of 4.2 – 14. Conclusion An elevated CD4/CD8 ratio on FCM is a nonspecific finding which may be seen in both reactive and lymphoproliferative disorders. The cytomorphologic features of the smear are more relevant than the sole flow cytometric finding of an elevated CD4/CD8 ratio.


Breast Journal | 2012

Nonimage-guided fine needle aspiration biopsy of palpable axillary lymph nodes in breast cancer patients.

Jennifer L. Marti; Diego Ayo; Pascale Levine; Osvaldo Hernandez; John Rescigno; Deborah Axelrod

Synopsis  We report the utility of office‐based, nonimaged guided fine needle aspiration of palpable axillary lymph nodes in breast cancer patients. We examine the sensitivity and specificity of this procedure, and examine factors associated with a positive fine needle aspiration biopsy result.


Diagnostic Cytopathology | 2008

Plasmablastic lymphoma involving breast: a case diagnosed by fine-needle aspiration and core needle biopsy.

Jun Wang; Osvaldo Hernandez; Filiz Şen

Plasmablastic lymphoma (PBL) is a rare lymphoma originating from B‐cells with terminal differentiation. Most common anatomic site involved by PBL is the oral cavity. Involvement of other body sites has only rarely been reported. Herein, we report a rare case of EBV‐negative PBL involving the breast of an HIV positive 47‐year‐old woman. The patient presented with decreased vision and photophobia. During physical examination, she was found to have bilateral breast masses and multiple lymphadenopathy. Fine‐needle aspiration of one of the breast masses showed large malignant cells with plasmacytoid features. Immunohistochemical studies performed on the core biopsy showed that the tumor cells were positive for common leukocyte antigen CD45 and plasma cell marker CD138, but negative for the pan‐B cell markers CD20 and CD79a. Molecular genetic studies showed clonal rearrangement of the immunoglobulin kappa light chain gene. This is the first case of PBL involving the breast reported in English cytological literature. Diagn. Cytopathol. 2008;36:257–261.


Clinical Imaging | 2015

Polyacrylamide gel breast augmentation: report of two cases and review of the literature

Nathaniel E. Margolis; Brian Bassiri-Tehrani; Chloe M. Chhor; Cory Singer; Osvaldo Hernandez; Linda Moy

Polyacrylamide gel (PAAG) injection remains an uncommon method of breast augmentation. Providers must recognize the clinical and radiological manifestations to optimize management. The clinical and radiological findings of PAAG injection may mimic malignancy and silicone breast augmentation. We described two patients with prior PAAG breast augmentation with physical exam and imaging findings concerning for malignancy. We reviewed the literature on PAAG breast augmentation and compare PAAG to silicone breast augmentation. The management of such patients is discussed.


Cytopathology | 2018

Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP); An Interobserver Study of Key Cytomorphologic Features From a Large Academic Medical Center

Tamar C. Brandler; Margaret Cho; Xiao-Jun Wei; Anthony Simms; Pascale Levine; Osvaldo Hernandez; Thaira Oweity; Fang Zhou; Aylin Simsir; Lisa Rosen; Wei Sun

Because of the indolent nature of noninvasive follicular thyroid neoplasm with papillary‐like nuclear features (NIFTP) and potential requisite for a more conservative treatment, it is crucial to identify features of this entity preoperatively. Our group recently published findings that there are several cytomorphological features that may be used as clues to distinguish NIFTP, papillary thyroid carcinoma (PTC) and follicular adenoma (FA) on fine needle aspiration. Therefore, we aimed to determine the interobserver reproducibility of these findings.


Human Pathology | 2005

Fascin-1 expression in papillary and invasive urothelial carcinomas of the urinary bladder

Guo-Xia Tong; Herman Yee; Luis Chiriboga; Osvaldo Hernandez; Jerry Waisman


Diagnostic Cytopathology | 2004

Human T-Lymphotropic Virus Type-1 Related Adult T-cell Leukemia/Lymphoma Presenting as a Parotid Mass Diagnosed By Fine-Needle Aspiration Biopsy

Guoxia Tong; Osvaldo Hernandez; Herman T. Yee; Shyun-Hua Zheng; Grace C.H. Yang


Journal of the American Society of Cytopathology | 2017

Cytomorphology of Noninvasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP): An Interobserver Study from a Large Academic Medical Center

Tamar C. Brandler; Margaret Cho; Xiao-Jun Wei; Anthony Simms; Pascale Levine; Osvaldo Hernandez; Thaira Oweity; Judy Zhong; Fang Zhou; Aylin Simsir; Wei Sun


Journal of the American Society of Cytopathology | 2013

Emphasizing the Role of Cytomorphologic Features in Diagnosing Solid Pseudopapillary Neoplasm of the Pancreas (SPN)

Melissa Yee-Chang; Rajiv Pulinthanathu; Shi Yan; Aylin Simsir; Osvaldo Hernandez; Xiao-Jun Wei

Collaboration


Dive into the Osvaldo Hernandez's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Guo-Xia Tong

Columbia University Medical Center

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge