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N A Young

Publications and source records attributed to N A Young.

At least 19 recordsLinked to original sources
PubMed1999

Diagnosis of lymphoma by fine-needle aspiration cytology using the revised European-American classification of lymphoid neoplasms.

BACKGROUND: Recent changes in the classification of non-Hodgkin lymphoma (NHL) emphasize the diagnostic importance of cytomorphology, immunophenotyping, and molecular findings in addition to histology. These changes have allowed for a greater role of fine-needle aspiration cytology (FNA) in the diagnosis of NHL. METHODS: A review of the English language literature regarding the use of FNA in the cytodiagnosis of lymphoma was performed. The revised European-American classification of lymphoid neoplasms (REAL) was reviewed in the context of its adaptability to the cytologic diagnosis of lymphoid neoplasms. RESULTS: FNA is being used more frequently in the diagnosis, staging, and follow-up of lymphoma whenever supportive studies are readily available. Cytomorphologic, immunophenotypic, and molecular criteria as well as pitfalls in the diagnosis of lymphoma by FNA have been delineated. Information was compiled into tables to facilitate correlation of criteria with the proposed REAL system. CONCLUSIONS: Many cases of NHL can be diagnosed and subclassified by FNA when there is adequate immunophenotypic information. Cancer (Cancer Cytopathol)

Biopsy, Needle↗
PubMed1998

Utilization of fine-needle aspiration cytology and flow cytometry in the diagnosis and subclassification of primary and recurrent lymphoma.

BACKGROUND: The primary diagnosis of non-Hodgkin's lymphoma/leukemia (NHL) by fine-needle aspiration (FNA) is controversial. The authors reviewed their experience with FNA and flow cytometry (FC) to determine the usefulness and limitations of these techniques in the diagnosis of NHL. METHODS: Slides and reports from all lymph node and extranodal FNAs performed during the period July 1993 to January 1997 with a diagnosis of lymphoma or benign lymphoid process were reviewed. Clinical and biopsy follow-up data were recorded. Results were tabulated and the usefulness of cytology was analyzed. RESULTS: There were 100 adequate aspirates from 87 patients. These included 72 cases of NHL, 58 (80%) of which were diagnosed by FNA and FC without the need for histologic sampling (69% of the primary lymphomas and 88% of the recurrent lymphomas). There were 22 aspirates suspicious for lymphoma, 12 equivocal results, and 7 benign diagnoses. Eighty-six percent of malignant FNAs (50 of 58) had flow cytometry (FC) as compared with only 15% (5 of 34) of the suspicious or equivocal FNAs. CONCLUSIONS: FNA is a valuable method for diagnosing and subclassifying NHL, although immunophenotyping by FC is often an essential ancillary test. In our experience, correlating the FNA results with the FC results can eliminate the need for a more invasive surgical biopsy in many cases.

Biopsy, Needle↗
PubMed1998

Preoperative chemotherapy of chemoradiotherapy for the treatment of adenocarcinoma of the pancreas and ampulla of Vater.

Much has been written about preoperative strategies in the treatment of pancreatic adenocarcinoma, yet there has been very little comment concerning other periampullary malignancies. This review discusses current issues relevant to the further development of preoperative adjuvant treatment of pancreatic adenocarcinoma. A small series of patients with ampullary adenocarcinomas treated with preoperative adjuvant chemoradiotherapy is also described.

Adenocarcinoma↗
PubMed1997

The value of transformed lymphocyte count in subclassification of non-Hodgkin's lymphoma by fine-needle aspiration.

No established criteria exist for predicting lymphoma grade or transformation in cytologic material. We counted transformed lymphocytes in fine-needle aspiration (FNA) biopsy specimens to determine whether the percentage of these cells in the smear could predict the histologic grade, the biologic behavior, or both. The percentage of transformed lymphocytes out of total lymphoid cells was determined on Papanicolaou-stained smears. Afterward, a cytodiagnosis was based on clinical information available at the time of the FNA, cytomorphologic data, and flow cytometry data. Results were correlated with results of examination of the surgical biopsy specimen, clinical behavior of the lymphoma, or both. The percentage of transformed lymphocytes was 10% or less in all low-grade or indolent lymphomas. Aspirates with transformed lymphocyte counts of 20% or greater were aggressive lymphomas. We also report our experience in the diagnosis of non-Hodgkin's lymphoma by FNA using cytomorphologic examination and immunophenotyping by flow cytometry at a cancer referral hospital. This is a preliminary study, and larger series may help establish the ranges of transformed lymphocyte counts that correlate with the lymphoma subtype.

Biopsy, Needle↗
PubMed1995

Zinc co-ordination in the DNA-binding domain of the yeast transcriptional activator PPR1.

The structure of the native zinc form of the DNA binding domain in the yeast transcriptional activator PPR1 was investigated by extended X-ray absorption fine structure (EXAFS). By carrying out the EXAFS measurements at 11k we were able to demonstrate explicitly the proximity of the two zinc ions (Zn-Zn distance = 3.16 +/- 0.03 A) and the presence of bridging cysteine ligands. The results show that the six cysteine residues co-ordinate two zinc ions in a two-metal ion cluster. PPR1 is the first member of this class of protein for which such information has been obtained.

Binding Sites↗
PubMed1994

Interobserver variability of cervical smears with squamous-cell abnormalities: a Philadelphia study.

The reproducibility of reporting squamous lesions by the Bethesda System (TBS) was evaluated by distributing 20 slides to be classified among 5 panelists considered experts in the field of cytopathology. Four cases were chosen for their classic morphology and the remainder were foreseen to produce possible discrepancies within one diagnostic category. For 7/20 (35%) cases there was unanimous agreement. Participants disagreed within one category of magnitude for seven (35%) cases. In six (30%) cases there was a range of more than one category disagreement. However, additional written comments modifying TBS diagnoses often diminished the clinical significance of these discrepancies. We conclude that despite the important role of TBS in standardization of Pap smear reports, a great degree of subjectivity exists in classifying squamous abnormalities without "classic" morphology. The lack of reproducibility should be taken into account in cytology proficiency testing.

Carcinoma, Squamous Cell↗
PubMed1994

Three-dimensional volumetric ultrasound imaging of arterial pathology from two-dimensional intravascular ultrasound: an in vitro study.

The objectives of this study were to evaluate: (1) the feasibility of generating three-dimensional (3-D) ultrasound (US) volumetric images of arterial segments from intravascular (IV) US images by retaining full range of gray levels; (2) the feasibility of volumetric quantitation of various arterial wall pathology from the 3-D volume US images of arterial segments. IVUS provides morphologic details of arterial wall diseases. This is seen as variation in gray levels. However, when a 3-D US image is generated currently, the full range of gray levels is not utilized. This limits optimal assessment of arterial wall pathology. Sequential cross-sectional IVUS images from 11 arterial segments consisting of various pathology were obtained in vitro by calibrated withdrawal of an IVUS catheter. These images were digitized by an 8 bit digitizer to retain full 256 gray levels of brightness. 3-D volume generation was carried out using "ANALYZE" software. After the IVUS imaging, arterial segments were sectioned transversely in a 0.3-0.4 mm cross section and stained with hematoxylin, eosin and elastin. Geometrical measurements and gross morphological changes of the arterial segments were noted and correlated with the corresponding section of the image from the three-dimensional volume. Arterial wall pathology, its extent and its effect on lumen geometry were easily appreciated in multiple tomographic sections of a 3-D volume image. Similarly, arterial wall pathology was easily quantitated from 3-D volume. The above assessments were only feasible by retaining full range of gray levels in the 3-D volume image. This study indicates that (1) it is feasible to generate a 3-D US volume image by retaining full range of gray levels from IVUS images, (2) retaining full range of gray levels allows optimal assessment of arterial wall pathology and its extent in 3-D volume, and (3) IVUS allows quantitation of arterial wall pathology, and thereby one can assess the effect of intervention.

Arteries↗
PubMed1994

Ischemic changes in fetal myocardium. An autopsy series.

It has been assumed that fetal myocardial necrosis is an uncommon event that occurs only under unusual circumstances. We studied random heart sections on 76 fetal and perinatal autopsies from a 4-year period to determine the types and frequency of histologic abnormalities that occur in fetal myocardium. Vacuolar degeneration was extremely common (43% of stillbirths, 84% of live births) but a nonspecific finding. Ischemic changes, which are typically associated with coagulation necrosis, myofiber waviness, or contraction band necrosis, were seen in 21% of stillbirths and 32% of live births. In the majority of cases with histologic evidence of ischemic change, a combination of either contraction band necrosis, coagulation necrosis, and/or myofiber waviness was identified. Only rarely was any one of the abnormalities seen as an isolated feature. In only two autopsies were the ischemic changes identified in the initial autopsy report. We conclude that the histologic changes associated with ischemia that may represent myocardial necrosis are not uncommon and are frequently overlooked at autopsy.

Autolysis↗
PubMed1993

Respiratory cytology: a review of non-neoplastic mimics of malignancy.

Respiratory cytology has its share of pitfalls. Some, such as vegetable cell contaminants, pose problems for only inexperienced observers, while others, such as reactive bronchoalveolar cells from pneumonia, can lead even experienced cytopathologists to make a misdiagnosis of malignancy. This review illustrates and analyzes those benign conditions or entities known to mimic malignancy in exfoliative respiratory cytology and fine-needle aspiration biopsy of the lung. Entities are grouped by the type of malignancy they mimic, and guidelines are presented for avoiding specific pitfalls.

Adenocarcinoma↗
PubMed1993

Diagnostic value of electron microscopy on paraffin-embedded cytologic material.

Transmission electron microscopy (TEM) is an important adjuvant to light microscopy, but is underutilized in cytopathology because of technical obstacles. One should attempt to obtain properly fixed material for TEM whenever possible. If that is not available, TEM on the cell block requires no preplanning or additional needle passes, and avoids problems of inadequate tissue for diagnosis. However, cell blocks are often not examined because of the perception that their poor ultrastructural preservation precludes their utility. We describe our experience in performing TEM on cell blocks from 15 cytologic specimens. In 13 of 15 cases, the cell block material was adequate for ultrastructural evaluation, and it clarified or extended the diagnosis in seven of these cases. TEM is a useful adjuvant technique to cytodiagnosis and can be successfully performed on cell blocks when gluteraldehyde-fixed material is not available.

Adenocarcinoma↗
PubMed1993

Value of repeat cervical smears at the time of colposcopic biopsy.

At our institution, gynecologists perform Pap smears not only as an initial screening procedure but also at the time of colposcopy and biopsy. We compared the results of initial Papanicolaou (Pap) smears with those taken at colposcopic biopsy to determine if repeating the Pap smear at the time of colposcopy contributed to patient management. We found that repeat colposcopic smears often agreed with the referral smears and biopsies. When there was disagreement, the colposcopic smear was more often a lower grade than the referral smear and correlated best with the biopsy. Both referral and colposcopic smears underestimated the severity of cervical lesions with the same frequency. We could document only 5/414 (1.2%) colposcopic smears that contributed to patient care.

Biopsy↗
PubMed1993

An implementation plan for autopsy quality control and quality assurance.

The few guidelines that exist for performing autopsy quality assurance are vague. Much has been written about the use of the autopsy to monitor clinical services, but not how to monitor the quality of the autopsy and autopsy reports. We present the comprehensive quality assurance program that has been developed and implemented at Hahnemann University Hospital, Philadelphia, Pa, for the past 2 years; this program has encompassed quality control of our diagnostic work. Key features have included in-depth peer review of completed reports, documentation of review at conferences, and careful monitoring of turnaround time. We have found that integrating quality assurance into departmental conferences is a useful supplement to in-depth peer review of randomly chosen autopsies. Our approach to quality assurance may serve as a model for other pathology departments, particularly those with pathology residency training programs.

Autopsy↗