bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Axillary Sentinel Lymph Node Biopsy by Immunohistochemistry and Multilevel Sectioning in Patients With Breast Carcinoma
Authors: Liu Lucy H. , Siziopikou Kalliopi P. , Gabram Sheryl , McClatchey Kenneth D.
Published: January 2021

Background.—Axillary lymph node dissection for evaluation of the presence or absence of metastatic disease is the single most important prognostic factor for patients with newly diagnosed primary breast cancer. Recently, sentinel lymph node (SLN) biopsy is being investigated as an alternative to the evaluation of the entire axilla. We evaluated whether the application of multilevel sectioning and immunohistochemistry in SLNs will increase the accuracy of detection of metastatic deposits.

Methods.—Between October 1998 and July 1999, 38 patients with breast carcinoma (25 ductal, 5 lobular, 4 tubular, and 4 mixed ductal and lobular) underwent successful SLN biopsy followed by complete axillary node dissection. Sentinel lymph nodes were localized with a combination of isosulfan blue dye and radionuclide colloid injection. Frozen sections and permanent sections of SLNs were examined. All negative SLNs were examined for micrometastases by 3 additional hematoxylin-eosin (H&E)-stained sections and immunohistochemistry with the cytokeratins AE1/AE3.

Results.—Sentinel lymph nodes were successfully identified surgically in 38 (93%) of 41 patients. There was a 97% correlation between the results of the frozen sections and the permanent H&E-stained sections. Twelve (32%) of 38 patients showed evidence of metastatic disease in their SLN by routine H&E staining. In 7 (58%) of 12 patients with positive nodes, the sentinel node was the only positive node. The 26 patients with negative SLN examination by H&E were further analyzed for micrometastases; 5 (19%) were found to have metastatic deposits by immunohistochemistry. Of these patients, 2 were also converted to node positive by detection of micrometastatic disease by examination of the additional H&E levels.

Conclusions.—Sentinel lymph nodes can be accurately identified in the axilla of breast cancer patients. Evaluation of SLNs provides reliable information representative of the status of the axilla in these patients. Immunohistochemistry and, to a lesser degree, detailed multilevel sectioning are able to further improve our ability to detect micrometastatic disease in SLNs of breast cancer patients.
The Institute of Medicine's Report on Medical Error
Authors: Sirota Ronald L.
Published: January 2021

Context.—During the past several years, more attention has been focused on the topics of medical error and patient safety than in the past. At the end of 1999, the Institute of Medicine (IOM) published a seminal report concerning medical error in the United States; this report will have sweeping implications for all disciplines of medicine, including pathology.

Objective.—To review the major findings of the IOM report on medical error and to discuss their implications for the field of pathology.

Methods.—Review of the IOM report on medical error and discussion of other relevant literature on medical error.

Results.—The IOM report on medical error highlights an unacceptable rate of medical error in the United States and mandates a 50% reduction in medical error during the next 5 years. It recommends regulatory solutions to this problem, as well as organizational approaches to error reduction. It proposes both mandatory and voluntary systems for reporting of medical error. The report suggests that systems should be examined for latent flaws and that individual culpability for error should not be overemphasized. The report recommends that error-reduction strategies that have been applied to other industries should be studied and that known concepts of error reduction should be applied to medicine. Strategies that the IOM suggests can be applied to pathology.

Conclusions.—Medical error occurs at an unacceptably high rate. Recommendations made in the IOM report on medical error and patient safety should be applied to the practice of pathology.
A Case of Small Polypoid Esophageal Carcinoma With Multidirectional Differentiation, Including Neuroendocrine, Squamous, Ciliated Glandular, and Sarcomatous Components
Authors: Kanamoto Akira , Nakanishi Yukihiro , Ochiai Atsushi , Shimoda Tadakazu , Yamaguchi Hajime , Tachimori Yuji , Kato Hoichi , Watanabe Hiroshi
Published: January 2021

A small composite esophageal carcinoma measuring 1.5 × 1.4 × 1.0 cm is described. The tumor had a polypoid elevation with a superficial extension. Histologic examination revealed invasion of the submucosal layer and multidirectional differentiation, including neuroendocrine, squamous, ciliated glandular, and sarcomatous components. The neuroendocrine component was strongly positive for chromogranin and formed the bulk of the polypoid tumor. The squamous cell carcinoma exhibited a superficial extension. The adenocarcinoma was located in a small region of the tumor and contained ciliated glandular cells. The spindle cell sarcomatous component, which was positive for α-smooth muscle actin and negative for cytokeratin, exhibited no specific mesenchymal differentiation. Each component was found in 60%, 10%, 5%, and 25% of the tumor, respectively. Cases of small composite esophageal carcinoma containing various carcinomatous and sarcomatous components are extremely rare.
Cholangiocarcinoma Occurring in a Liver With Multiple Bile Duct Hamartomas (von Meyenburg Complexes)
Authors: Röcken C. , Pross M. , Brucks U. , Ridwelski K. , Roessner A.
Published: January 2021

A 59-year-old woman presented with epigastric pain and weight loss. Ultrasound, computed tomography, and magnetic resonance imaging scans of the abdomen showed a tumor in segments 6 and 7 of the right liver lobe, measuring 8 cm in greatest diameter. The tumor was subsequently resected, and histopathology showed a poorly differentiated adenocarcinoma immunoreactive for CA 19-9 and cytokeratin 19. In the absence of any other clinically detectable primary tumor, the lesion was diagnosed as a peripheral intrahepatic cholangiocarcinoma. In addition, multiple bile duct hamartomas were found in the surrounding parenchyma. The tumor was unrelated to Caroli disease, primary sclerosing cholangitis, ulcerative colitis, or nonbiliary cirrhosis, as demonstrated by further clinical and histopathologic investigations, but probably was associated with the presence of multiple bile duct hamartomas. To our knowledge, this is the eighth reported case of a cholangiocarcinoma associated with multiple bile duct hamartomas.
Atypical Hairy Cell Leukemia
Authors: Wu Mark L. , Kwaan Hau C. , Goolsby Charles L.
Published: January 2021

The morphologic differential diagnosis of mature B-cell neoplasms with cytoplasmic projections includes splenic lymphoma with villous lymphocytes and hairy cell leukemia. Although the classification of hairy cell leukemia is not universally recognized, 3 variants have been described, namely, classic, variant, and Japanese variant, each of which has different clinical and immunophenotypic features. Classic hairy cell leukemia is virtually always CD11c+, CD25+, and CD103+. Variant and Japanese variant hairy cell leukemias are usually CD11c+, always CD25−, and occasionally CD103+. Each variant is characteristically CD10−. We present a case of hairy cell leukemia with a unique immunoprofile in that the cells were CD10+, CD25+, and CD103−, and we review the criteria helpful in differentiating “hairy” B-cell neoplasms. This case emphasizes the variability of hairy cell leukemia and the need to correlate all clinical and pathologic data in reaching a diagnosis.
Pathologic Evaluation of Sentinel Lymph Nodes in Colorectal Carcinoma
Authors: Wiese David A. , Saha Sukamal , Badin Julio , Ng Peter S-T. , Gauthier Jerry , Ahsan Aamir , Yu Lelia
Published: January 2021

Background.—The identification of lymph node metastases in colorectal resection specimens is necessary for accurate tumor staging. However, routine lymph node dissection by the pathologist yields only a subset of nodes removed surgically and may not include those nodes most directly in the path of lymphatic drainage from the tumor. Intraoperative mapping of such sentinel lymph nodes (SLNs) has been reported in cases of melanoma and breast cancer. We applied a similar method to cases of colorectal carcinoma, with emphasis on the pathology of the SLNs.

Methods.—Eighty-three consecutive patients with colorectal carcinoma were evaluated after intraoperative injection of 1 to 2 mL of 1% isosulfan blue dye (Lymphazurin) into the peritumoral subserosa. Blue-stained lymph nodes were suture-tagged by the surgeon within minutes of the injection for identification by the pathologist, and a standard resection was performed. Designated SLNs were sectioned at 10 levels through the block; a cytokeratin immunostain (AE1) was also obtained. To evaluate the possibility that increased detection of metastases in the SLN might be solely due to increased histologic sampling, all initially negative non-SLNs in the first 25 cases were sectioned also at 10 levels.

Results.—Sentinel lymph nodes were identified intraoperatively in 82 (99%) of 83 patients and accounted for 152 (11.9%) of 1275 lymph nodes recovered, with an average of 1.9 SLNs per patient. A total of 99 positive lymph nodes (38 positive SLNs and 61 positive non-SLNs) were identified in 34 node-positive patients. The SLNs were the only site of metastasis in 17 patients (50%), while 14 patients (41%) had both positive SLNs and non-SLNs. Three patients (9%) had positive non-SLNs with negative SLNs, representing skip metastases. In patients with positive SLNs, 91 (19%) of 474 total lymph nodes and 53 (12%) of 436 non-SLNs were positive for metastasis. In patients with negative SLNs, 8 (1%) of 801 total lymph nodes and 8 (1.2%) of 687 non-SLNs were positive for metastasis. Multilevel sections of 330 initially negative non-SLNs in the first 25 patients yielded only 2 additional positive nodes (0.6%). All patients with positive SLNs were correctly staged by a combination of 4 representative levels through the SLN(s) together with a single cytokeratin immunostain.

Conclusions.—Intraoperative mapping of SLNs in colorectal carcinoma identifies lymph nodes likely to contain metastases. Focused pathologic evaluation of the 1 to 4 SLNs so identified can improve the accuracy of pathologic staging.
M30 Expression Demonstrates Apoptotic Cells, Correlates With In Situ End-Labeling, and Is Associated With Ki-67 Expression in Large Intestinal Neoplasms
Authors: Carr Norman John
Published: January 2021

Context.—The monoclonal antibody M30 recognizes a neoepitope of cytokeratin 18 produced during apoptosis. It is reactive in formalin-fixed, paraffin-embedded tissue and has great potential in the study of apoptosis in clinical and experimental material.

Objectives.—To compare the results of M30 immunoexpression with a more established technique of demonstrating apoptosis in tissue sections, in situ end-labeling. A secondary objective was to compare the results with immunoexpression of the proliferation-associated antigen Ki-67.

Design.—Retrospective analysis of adenomas and adenocarcinomas of the large intestine.

Interventions.—Immunohistochemistry for M30 and Ki-67, and in situ end-labeling. Formalin-fixed, paraffin-embedded tissue was used.

Main Outcome Measures.—The number of cells positive for M30, Ki-67, and in situ end-labeling, expressed as a proportion of the total number of cells counted.

Results.—A strong positive correlation was found between in situ end-labeling and expression of M30, although the counts were widely scattered around the regression line. Counts of Ki-67 were strongly correlated with both M30 expression and in situ end-labeling. Immunoexpression of M30 was generally easier to interpret than in situ end-labeling, and the procedures for M30 immunohistochemistry were technically less exacting.

Conclusion.—These findings support the application of M30 immunoreactivity in the study of apoptosis.
CD13-Positive Anaplastic Large Cell Lymphoma of T-Cell Origin—A Diagnostic and Histogenetic Problem
Authors: Popnikolov Nikolay K. , Payne Deborah A. , Hudnall S. David , Hawkins Hal K. , Kumar Manjusha , Norris Brent A. , Elghetany M. Tarek
Published: January 2021

The expression of myelomonocytic-associated antigens in anaplastic large cell lymphomas (ALCLs), particularly those presenting in extranodal sites, can make their distinction from extramedullary myeloid cell tumors (EMCTs) or histiocytic tumors problematic. Yet, this distinction is clinically significant because of its therapeutic and prognostic implications. Herein, we describe a case of extranodal anaplastic lymphoma kinase–positive CD30-positive ALCL of T-cell origin in a 12-year-old boy, which was initially called an EMCT because of the expression of CD13 and HLA-DR detected by flow cytometry and the absence of other T-cell–related surface markers. However, the detection of cytoplasmic CD3 by flow cytometry prompted further studies. The tumor was composed of large cells with abundant slightly eosinophilic vacuolated cytoplasm and ovoid or reniform nuclei with a few small nucleoli. Using immunohistochemistry, the tumor was positive for CD45, CD30, CD45RO, and CD43 with a strong cytoplasmic and nuclear anaplastic lymphoma kinase stain. The tumor cells showed a T-cell clonal genotype. Electron microscopy revealed no ultrastructural features of myelomonocytic or histiocytic origin. The patient responded well to the chemotherapy and was in complete remission for 10 months at the time of submission of this manuscript. Review of the literature showed inconsistencies regarding the diagnosis, nomenclature, and, therefore, treatment and prognosis of these tumors. In addition, the CD13 expression in ALCL raises some histogenetic questions and may indicate origin from a pluripotent stem cell, misprogramming during malignant transformation, or a microenvironmental effect on lymphoid cell expression of surface antigens. Therefore, ALCL should be considered in the differential diagnosis of EMCTs or histiocytic tumors, particularly when surface marker lineage assignment is ambiguous.
Primary Nodal Marginal Zone B-Cell Lymphoma Arising From More Than One Clonal Neoplastic Population
Authors: Finch Clara N. , Nichols Margaret , Shrimpton Antony , Liu Dating , Hutchison Robert E.
Published: January 2021

Primary nodal marginal zone B-cell lymphoma is an uncommon monoclonal B-cell lymphoproliferative disorder. We report a case of a 79-year-old woman who presented with generalized lymphadenopathy. Histologic and immunohistochemical examinations of biopsy sections from an axillary lymph node were consistent with nodal marginal zone B-cell lymphoma. Flow cytometry analysis showed 2 distinct clonal B-cell populations expressing λ or κ light chain restriction. Subsequently, genomic deoxyribonucleic acid (DNA) isolated from a paraffin-embedded lymph node section was analyzed for the presence of gene rearrangements. Polymerase chain reaction (PCR) analysis of immunoglobulin heavy chain genes revealed 3 rearranged DNA bands, confirming the presence of more than one clonal B-cell population. These immunophenotypic and genotypic findings have not been previously described in association with this type of lymphoma. To our knowledge, this represents the first reported case of biclonal nodal marginal zone B-cell lymphoma.
Comparative Genomic Hybridization
Authors: Barrett Irene J. , Lomax Brenda L. , Loukianova Tatiana , Tang Steven S. , Lestou Valia S. , Kalousek Dagmar K.
Published: January 2021

Objective.—To demonstrate the effectiveness of comparative genomic hybridization (CGH) for analysis of reproductive pathology specimens in clinical cytogenetics laboratories.

Design.—A total of 856 CGH analyses were performed on various placental and fetal tissues derived from 368 specimens of spontaneous abortions and on placentas from 219 pregnancies with live-born infants. The live-born infants were clinically evaluated as normally developed, with either a normal birth weight or with intrauterine growth restriction; some live-born infants had an abnormal prenatal triple screen with normal cytogenetic results on amniotic fluid cell cultures.

Results.—Comparative genomic hybridization analysis was successfully performed on 856 samples from spontaneously aborted specimens and term placentas. Failure of analysis occurred in 1.6% of samples and was due to an insufficient amount of tissue for DNA extraction. Comparative genomic hybridization identified aneuploidy in 53% of spontaneous abortion samples and 3.1% of term placentas.

Conclusions.—Comparative genomic hybridization analysis is a useful clinical tool for detection of aneuploidy in placental and fetal tissues. It provides a genome-wide screen while eliminating tissue culture failures, culture artifacts, and maternal cell contamination. We present practical guidelines for interpreting CGH profiles derived from human reproductive specimens.
The PlA Polymorphism of Glycoprotein IIIa Functions as a Modifier for the Effect of Estrogen on Platelet Aggregation
Authors: Boudoulas Konstantinos D. , Cooke Glen E. , Roos Christine M. , Bray Paul F. , Goldschmidt-Clermont Pascal J.
Published: January 2021

Background.—Although estrogen has been shown to contribute to retardation of the development of coronary heart disease in premenopausal women, the efficacy of hormone replacement therapy for coronary heart disease prevention in women with established coronary heart disease remains controversial. Hence, additional research is needed to clarify the effects of hormone replacement therapy on the cardiovascular and clotting systems. We investigated the effect of estrogen on platelet aggregation induced by standard agonists (epinephrine and adenosine diphosphate), with and without the platelet antagonist aspirin. Furthermore, we analyzed our data according to the presence or absence of a prevalent polymorphism of the glycoprotein (GP) IIIa subunit of the platelet fibrinogen receptor GPIIb-IIIa, PlA2.

Methods and Results.—The effect of estrogen on aggregation of platelets was studied in healthy men (n = 20, 10 PlA1/A1 and 10 PlA1/A2) and premenopausal healthy women (n = 10, 5 PlA1/A1 and 5 PlA1/A2). The PlA1/A1 and PlA1/A2 individuals were matched for age and race. Platelet response to agonists was investigated in the presence of (1) estrogen (10−11 to 10−8 mol/L), (2) aspirin (0.056 to 56 μmol/L), (3) estrogen plus aspirin, and (4) estrogen plus ICI 182 780 (ICI, 10−9 mol/L, an inhibitor of the estrogen receptor). We found that physiologic concentrations of estrogen strongly and significantly inhibited the aggregation of PlA1/A2 platelets (P ;lt .005 for epinephrine and P ;lt .05 for adenosine diphosphate, induced aggregation, respectively) in both men and women. Concentrations of estrogen that were 1000-fold greater were required to observe the same level of inhibition with PlA1/A1 platelets. In the presence of aspirin, estrogen failed to provide additional inhibitory effect on aggregation of both PlA1/A1 and PlA1/A2 platelets. The estrogen-specific inhibitor ICI blocked the effect of estrogen on aggregation, suggesting that this effect is mediated by the estrogen receptor.

Conclusions.—Estrogen inhibits the aggregation of platelets, but such inhibition is highly dependent on the presence or absence of the PlA2 polymorphism of GPIIIa. However, in the presence of aspirin, the inhibitory effect of estrogen on aggregation was no longer detectable.
Use of Buccal Cells Collected in Mouthwash as a Source of DNA for Clinical Testing
Authors: Heath Ellen M. , Morken Nathaniel W. , Campbell Kristen A. , Tkach Dennis , Boyd Erin A. , Strom Daniel A.
Published: January 2021

Context.—To maximize the participation rate in population genetic studies, alternatives to invasive whole blood collection are increasing. One such alternative is buccal epithelial cell collection, which, in contrast to venipuncture and finger sticks, is painless. Buccal cells, if collected and purified efficiently, offer an acceptable source for DNA to be used in research and clinical applications.

Objective.—To develop a noninvasive sampling method for collecting cells for routine DNA testing in a clinical laboratory setting.

Design.—Five factors were used to evaluate several brands of mouthwash: (1) compatibility with the DNA purification chemistry, (2) DNA yield, (3) DNA quality, (4) DNA stability at room temperature, and (5) mouthwash taste. Next, an optimization study was undertaken to maximize DNA yield. Finally, a validation study was undertaken with the optimized protocol to test a panel of 14 donors for DNA yield and performance and to test for the stability of DNA held in mouthwash.

Setting.—Industrial research and development laboratory.

Results.—Of 5 mouthwashes tested, Scope brand mouthwash received the highest overall ranking. The addition of proteinase K and glycogen to the protocol significantly enhanced DNA yields, with a test panel (n = 14) giving a range of 12 to 60 μg of DNA per donor. In a 4-week room temperature stability study, the DNA in mouthwash samples was found to be stable for at least 2 weeks.

Conclusion.—A clinically validated DNA purification chemistry was adapted to a noninvasive specimen collection method. This method used a commercially available mouthwash, Scope, to collect buccal epithelial cells for the preparation of high-quality DNA in high yield.
Primary Leiomyosarcoma of the Pancreas
Authors: Nesi Gabriella , Pantalone Desiree , Ragionieri Ilaria , Amorosi Andrea
Published: January 2021

Primary leiomyosarcoma of the pancreas is a rare tumor for which only 21 reports appear in the world literature. We describe an additional case of pancreatic leiomyosarcoma in a 76-year-old man, who complained of persistent high fever. Histologic examination revealed a pleomorphic spindle cell tumor. Reactivity for muscle-specific actin, α-smooth muscle actin, and basement membrane components, along with negative staining for epithelial and neural markers, were consistent with a smooth muscle sarcoma. The patient died of disease 1 year after complete surgical excision. This report highlights the need to use a complete antibody panel in order to accurately immunophenotype pleomorphic malignant tumors of the pancreas. A review of the cases compiled in the literature indicates that pancreatic leiomyosarcoma, like its counterpart arising in deep soft tissues, is an aggressive neoplasm characterized by short survival and a high rate of metastases.
Immunostaining for Thyroid Transcription Factor 1 and Cytokeratin 20 Aids the Distinction of Small Cell Carcinoma From Merkel Cell Carcinoma, But Not Pulmonary From Extrapulmonary Small Cell Carcinomas
Authors: Cheuk W. , Kwan M. Y. , Suster Saul , Chan John K. C.
Published: January 2021

Objective.—To study the expression of thyroid transcription factor 1 (TTF-1) and cytokeratin 20 (CK20) in pulmonary small cell carcinomas, extrapulmonary small cell carcinomas, and Merkel cell carcinomas, and thereby determine whether these markers are helpful in distinguishing these 3 groups of small cell neuroendocrine carcinomas.

Materials and Methods.—Immunostaining for TTF-1 and CK20 was performed in 102 cases of small cell carcinoma (pulmonary, 52; extrapulmonary, 50) and 23 cases of Merkel cell carcinoma. The results for the 3 groups were compared.

Results.—Thyroid transcription factor 1 was expressed in 82.7% of pulmonary small cell carcinomas, 42.0% of extrapulmonary small cell carcinomas (range, 33.3–53.3% for the various sites), and 0% of Merkel cell carcinomas. Cytokeratin 20 staining was consistently negative in pulmonary small cell carcinomas, and positive in 4.0% of extrapulmonary small cell carcinomas and 100% of Merkel cell carcinomas.

Conclusions.—Immunostaining for TTF-1, especially when combined with immunostaining for CK20, can aid in the distinction between Merkel cell carcinoma and small cell carcinoma (both pulmonary and extrapulmonary). However, in individual cases, these markers cannot be used to distinguish between pulmonary and extrapulmonary small cell carcinomas due to the extensive overlap in immunophenotypes.
Distance of Lymph Nodes From the Tumor
Authors: Cserni Gábor , Tarján Miklós , Bori Rita
Published: January 2021

Context.—The nodal stage of colorectal cancers is prognostically important. Most current staging guidelines concentrate on the minimum number of evaluated lymph nodes required for an adequate node-negative stage.

Objective.—To evaluate the distance of the lymph nodes from the primary tumors as a possible qualitative feature that could help pathologists select between these nodes.

Design.—Prospective analysis of 100 colorectal carcinoma specimens.

Setting.—Department of Pathology of a medium-sized teaching hospital.

Patients.—Consecutive patients with colorectal cancer.

Interventions.—Nodes abluminal from the tumor and the adjacent bowel segments were recovered in 4 fractions (A through D) in 100 colorectal carcinoma specimens.

Main Outcome Measures.—Distribution of metastatic nodes in fractions A through D, and their influence on nodal stage.

Results.—All tumors but 1 were classified correctly as node-negative or node-positive on the basis of fraction A (nodes abluminal from the tumor and from the 1-cm-long segments proximal and distal to the tumor). All tumors but 1 were appropriately classified as pN0, pN1, or pN2 on the basis of fractions A and B (nodes abluminal from the tumor and from the 3-cm-long segments proximal and distal to the tumor).

Conclusions.—Lymph nodes should be recovered from fractions A and B, and if 3 nodes are reported positive, additional nodes should be sought to determine the extent of nodal involvement. This qualitative restriction of the grossing protocol may reduce the time spent in recovering nodes from colorectal carcinoma resection specimens.
Xanthogranulomatous Salpingitis and Oophoritis
Authors: Gray Yulia , Libbey N. Peter
Published: January 2021

A case of xanthogranulomatous salpingitis and oophoritis in a 47-year-old woman is presented. Xanthogranulomatous inflammation is an uncommon form of chronic inflammation that is destructive to affected organs; it is characterized by the presence of lipid-filled macrophages with admixed lymphocytes, plasma cells, and neutrophils. Only a few cases of xanthogranulomatous salpingitis and oophoritis have been reported to date. The case presented here is associated with Escherichia coli infection, endometriosis, and an intrauterine device.
A Practical Approach for Evaluating New Antibodies in the Clinical Immunohistochemistry Laboratory
Authors: Hsi Eric D.
Published: January 2021

Paraffin section immunohistochemistry (IHC) is widely used in diagnostic surgical pathology. Today, it is difficult to imagine the practice of surgical pathology without IHC. The availability of automated immunostainers with reagent rental contracts makes this technology commonplace. One potential danger is that many laboratories are now offering immunostains without significant prior knowledge or experience in IHC. As part of its mission, the Cell Markers Committee of the College of American Pathologists offers this manuscript as a basic guide to introducing new antibodies in the clinical IHC laboratory. Issues relating to regulatory developments, antibody selection, staining optimization, and test validation are addressed.
Posttransplantation Lymphoproliferative Disorders in Pediatric Patients Undergoing Liver Transplantation
Authors: Koh Bong Y. , Rosenthal Philip , Medeiros L. Jeffrey , Zhou Yuehua , Osorio Robert W. , Roberts John P. , Ascher Nancy L. , Gelb Arnold B.
Published: January 2021

Objectives.—To study the clinicopathologic and molecular genetic findings in posttransplantation lymphoproliferative disorders (PTLDs) following pediatric liver transplantation and to determine the applicability of a recently proposed consensus classification system.

Design.—The clinical, pathologic, and molecular genetic findings of 11 PTLDs that occurred in 10 patients are presented. These 10 patients were derived from a group of 121 pediatric patients who underwent liver transplantation at the University of California, San Francisco. The PTLDs were classified using the proposed Society for Hematopathology scheme. Clonality was determined by immunohistochemical detection of monotypic immunoglobulin or by using polymerase chain reaction–based methods to detect monoclonal immunoglobulin heavy-chain gene rearrangements. Epstein-Barr virus (EBV) was detected by immunohistochemistry, in situ hybridization, or polymerase chain reaction. Epstein-Barr virus typing and the presence of LMP1 gene deletions were also analyzed by polymerase chain reaction.

Results.—There were 3 early lesions, 4 polymorphic PTLDs, and 4 monomorphic PTLDs. Monoclonality was demonstrated in 8 of 9 cases assessed. Epstein-Barr virus was present in all cases; of 9 cases assessed by polymerase chain reaction, the virus was type A in 8 and type B in 1. No EBV LMP1 gene deletions were identified. The corresponding liver explants were negative for EBV in 8 cases and positive in 1 case. Greater than 3 foci of disease and monomorphic PTLD were associated with decreased actuarial survival (P < .05).

Conclusions.—The prognosis of pediatric patients with PTLD is favorable for early lesions and polymorphous PTLD, particularly in patients with localized disease. Multifocal disease and monomorphic PTLD are associated with an unfavorable prognosis.
Histologic Features of Zygomycosis
Authors: Frater John L. , Hall Gerri S. , Procop Gary W.
Published: January 2021

Objective.—Invasive zygomycosis is rapidly progressive and is associated with angioinvasion and infarction. Invasive disease requires emergent surgical and medical intervention. Because it is important for surgical pathologists to recognize these fungi and their preferential sites of growth, the objective of this article is to describe the fungal morphology and histopathologic findings in biopsies from patients with zygomycotic disease, with emphasis on preferential sites of fungal growth.

Design.—Medical record and histologic review identified 20 patients with zygomycosis. Inclusion criteria included the presence of typical ribbonlike hyphae and positive culture, a clinical history of invasive zygomycosis, or both. The histologic features of disease and the fungal morphology were assessed.

Results.—Fungus ball (15%), rhinocerebral (55%), and pulmonary (30%) disease were the types of disease represented. The inflammatory responses were predominantly neutrophilic (50%), predominantly granulomatous (5%), pyogranulomatous (25%), or absent (20%). Invasive disease was characterized by prominent infarcts (94%), angioinvasion (100%), and, surprisingly, prominent perineural invasion (90%) in biopsies that contained nerves for evaluation. At least rare hyphal septa were always seen (100%), and most branches (95%) varied from 45° to 90°.

Conclusions.—As known to mycologists, zygomycetes are pauciseptate, rather than aseptate, molds. Therefore, the presence of an occasional septum is expected. Perineural invasion is a common finding in invasive zygomycosis, as are angioinvasion and infarcts. Therefore, prior to excluding the presence of these fungi in biopsies suspected to contain zygomycetes, the perineural space should be carefully examined.
The New Hematology Analyzer Sysmex XE-2100
Authors: Ruzicka Katharina , Veitl Mario , Thalhammer-Scherrer Renate , Schwarzinger Ilse
Published: January 2021

Context.—The new hematology analyzer Sysmex XE-2100 (TOA Medical Electronics, Kobe, Japan) has a novel, combined, white blood cell differential technology and a special reagent system to enumerate nucleated red blood cells.

Design.—Performance evaluation of both technologies of the Sysmex XE-2100 according to the H20-A protocol of the National Committee for Clinical and Laboratory Standards and comparison of the results with those for the hematology analyzer Sysmex NE-8000 (TOA Medical Electronics).

Specimens.—Five hundred forty-four blood samples randomly chosen from various inpatient and outpatient departments of the Vienna University hospital.

Results.—Five-part white blood cell differential counts on the XE-2100 revealed excellent correlation with the manual reference method for neutrophils, lymphocytes, and eosinophils (r = .925, .922, and .877, respectively) and good correlation for monocytes and basophils (r = .756 and .763, respectively). The efficiency rates of flagging for the presence of ≥1% abnormal white blood cells were 83% (XE-2100) and 66% (NE-8000). The correlation of automated and microscopic nucleated red blood cell counts was excellent (r = .97).

Conclusions.—From the present evaluation and our former experience with other types of Sysmex analyzers, we conclude that the new white blood cell differential technology of the XE-2100 represents a further development toward more efficient flagging of abnormal white blood cells.
Aberrant Localization of the Neuronal Class III β-Tubulin in Astrocytomas
Authors: Katsetos Christos D. , Del Valle Luis , Geddes Jennian F. , Assimakopoulou Martha , Legido Agustin , Boyd James C. , Balin Brian , Parikh Nehal A. , Maraziotis Theodoros , de Chadarevian Jean-Pierre , Varakis John N. , Matsas Rebecca , Spano Anthony , Frankfurter Anthony , Herman Mary M. , Khalili Kamel
Published: January 2021

Background.—The class III β-tubulin isotype (βIII) is widely regarded as a neuronal marker in development and neoplasia. In previous work, we have shown that the expression of βIII in neuronal/neuroblastic tumors is differentiation dependent. In contrast, the aberrant localization of this isotype in certain nonneuronal neoplasms, such as epithelial neuroendocrine lung tumors, is associated with anaplastic potential.

Objective.—To test the generality of this observation, we investigated the immunoreactivity profile of βIII in astrocytomas.

Design.—Sixty archival, surgically excised astrocytomas (8 pilocytic astrocytomas, WHO grade 1; 18 diffuse fibrillary astrocytomas, WHO grade 2; 4 anaplastic astrocytomas, WHO grade 3; and 30 glioblastomas, WHO grade 4), were studied by immunohistochemistry using anti-βIII monoclonal (TuJ1) and polyclonal antibodies. A monoclonal antibody to Ki-67 nuclear antigen (NC-MM1) was used as a marker for cell proliferation. Antibodies to glial fibrillary acidic protein (GFAP) and BM89 synaptic vesicle antigen/synaptophysin were used as glial and neuronal markers, respectively.

Results.—The βIII immunoreactivity was significantly greater in high-grade astrocytomas (anaplastic astrocytomas and glioblastomas; median labeling index [MLI], 35%; interquartile range [IQR], 20%–47%) as compared with diffuse fibrillary astrocytomas (MLI, 4%; IQR, 0.2%–21%) (P < .0001) and was rarely detectable in pilocytic astrocytomas (MLI, 0%; IQR, 0%–0.5%) (P < .0001 vs high-grade astrocytomas; P < .01 vs diffuse fibrillary astrocytomas). A highly significant, grade-dependent relationship was observed between βIII and Ki-67 labeling and malignancy, but this association was stronger for Ki-67 than for βIII (βIII, P < .006; Ki-67, P < .0001). There was co-localization of βIII and GFAP in neoplastic astrocytes, but no BM89 synaptic vesicle antigen/synaptophysin staining was detected.

Conclusions.—In the context of astrocytic gliomas, βIII immunoreactivity is associated with an ascending gradient of malignancy and thus may be a useful ancillary diagnostic marker. However, the significance of βIII-positive phenotypes in diffuse fibrillary astrocytomas with respect to prognostic and predictive value requires further evaluation. Under certain neoplastic conditions, βIII expression is not neuron specific, calling for a cautious interpretation of βIII-positive phenotypes in brain tumors.
Ebola Virus Glycoprotein Demonstrates Differential Cellular Localization in Infected Cell Types of Nonhuman Primates and Guinea Pigs
Authors: Steele Keith , Crise Bruce , Kuehne Ana , Kell Wayne
Published: January 2021

Background.—In vitro studies have previously shown that Ebola virus glycoprotein (GP) is rapidly processed and largely released from infected cells, whereas other viral proteins, such as VP40, accumulate within cells.

Objective.—To determine infected cell types in which Ebola virus GP and VP40, individually, localize in vivo.

Methods.—Immunohistochemistry and in situ hybridization using GP- and VP40-specific antibodies and genetic probes were used to analyze archived tissues of experimentally infected nonhuman primates and guinea pigs and Vero E6 and 293 cells infected in vitro.

Results.—The GP antigen was consistently present in hepatocytes, adrenal cortical cells, fibroblasts, fibroblastic reticular cells, ovarian thecal cells, and several types of epithelial cells, but was not detected in macrophages and blood monocytes of animals, nor in Vero cells and 293 cells. All GP-positive and GP-negative cell types analyzed contained VP40 antigen and both GP and VP40 RNAs.

Conclusions.—Ebola virus GP appears to selectively accumulate in many cell types infected in vivo, but not in macrophages and monocytes. This finding suggests that many cell types may have a GP-processing pathway that differs from the pathway described by previous in vitro studies. Differential cellular localization of GP could be relevant to the pathogenesis of Ebola hemorrhagic fever.
GEWF Solution
Authors: Newell Ken J. , Sawka Barry W. , Rudrick Brian F. , Driman David K.
Published: January 2021

Background.—Lymph node status is an important prognostic factor in the staging of colorectal carcinoma. Several adjunctive solutions have been used to increase the yield of pericolic lymph nodes from colorectal cancer resection specimens.

Methods.—During 1998 at the Grey Bruce Regional Health Centre (Owen Sound, Ontario), 67 colonic resections were performed for colorectal cancer. Lymph nodes were identified using GEWF solution (glacial acetic acid, ethanol, distilled water, and formaldehyde) in 35 cases, and by the conventional method of sectioning, inspection, and palpation in 32 cases.

Results.—There were no significant differences between GEWF and non-GEWF cases with respect to patient age, length of resection, size of tumor, tumor histologic type, tumor differentiation, or depth of tumor penetration into the bowel wall. Use of GEWF led to a significant increase in the number of lymph nodes found (10.2 ± 4.9 per case) compared with non-GEWF cases (6.8 ± 3.9 per case) (P = .002). In GEWF cases 358 lymph nodes were identified, 82 with metastases, whereas in the non-GEWF cases 218 lymph nodes were found, 41 with metastases. The size of positive lymph nodes in the GEWF group (0.5 ± 0.2 cm) was significantly smaller than in the non-GEWF group (0.7 ± 0.4 cm) (P = .046). A greater percentage of positive lymph nodes in the GEWF cases (49/82, 60%) were 0.5 cm or smaller compared with the non-GEWF cases (17/41, 41%).

Conclusions.—GEWF increases the yield of lymph nodes recovered from colorectal cancer specimens and may lead to improved staging of this cancer; it is inexpensive and simple to use.
Correlation of Ki-67 and p53 With the New World Health Organization/International Society of Urological Pathology Classification System for Urothelial Neoplasia
Authors: Cina Stephen J. , Lancaster-Weiss Kristen J. , Lecksell Kristen , Epstein Jonathan I.
Published: January 2021

Objective.—The present study examines p53 and Ki-67 staining patterns of the diagnostic entities included within the new World Health Organization/International Society of Urological Pathology (WHO/ISUP) classification of urothelial neoplasms.

Design.—We retrospectively studied 151 bladder biopsies from 81 patients with the following neoplasms: normal urothelium (n = 34 biopsies); low-grade intraurothelial neoplasia (LGIUN; n = 19); high-grade intraurothelial neoplasia (HGIUN; n = 20); papillary hyperplasia (n = 4); papilloma (n = 3); papillary neoplasm of low malignant potential (LMP; n = 12); low-grade papillary carcinoma (n = 28); and high-grade papillary carcinoma (n = 31). Sections were labeled immunohistochemically with antibodies to p53 and Ki-67 (MIB-1). Two hundred cells from each lesion were visually counted, and the percentage of positive cells was tabulated without knowledge of the WHO/ISUP diagnosis.

Results.—In flat lesions, p53 positivity was of limited diagnostic utility; the marker was present in 6 of 34 benign biopsies, 6 of 19 LGIUNs, and 10 of 20 HGIUNs. In one case in which HGIUN was present elsewhere in the bladder, 29% of the benign urothelial cells were p53 positive. In papillary lesions, p53 positivity was not seen in 4 of 4 cases of papillary hyperplasia, 3 of 3 papillomas, and 8 of 12 LMP tumors. In contrast, p53 was detected in 18 of 28 low-grade and 26 of 31 high-grade papillary urothelial carcinomas. A p53 labeling index (LI) greater than 30% was only seen in HGIUNs and high-grade papillary carcinomas. In flat lesions, an increased Ki-67 LI separated out benign urothelium (mean LI, 0.62%) from dysplasia (mean LI, 3.3%) and HGIUN (mean LI, 11.6%). In papillary lesions, Ki-67 positivity was as follows: papillary hyperplasia (mean LI, 1.1%); papilloma (mean LI, 4.3%); LMP tumors (mean LI, 2.5%), low-grade papillary carcinoma (mean LI, 7.3%); and high-grade carcinoma (mean LI, 15.7%). A Ki-67 LI greater than 10% was seen only in low- and high-grade papillary carcinomas, HGIUN, and single cases of LGIUN and papillary neoplasm of LMP.

Conclusions.—An increased proliferative index as demonstrated by immunohistochemical staining for Ki-67 (MIB-1) is most often seen in papillary carcinoma and HGIUN. Marked p53 positivity is also characteristic of carcinoma but may be seen in benign-appearing urothelium, suggesting a “field effect” with occult molecular aberration.
Chronic Myelomonocytic Leukemia Revealed by Uncontrollable Hematuria
Authors: Bane A. L. , Enright H. , Sweeney E. C.
Published: January 2021

Nephrectomy was performed for uncontrollable unilateral hematuria in an apparently healthy 72-year-old man. The suburothelial connective tissue of the kidney was infiltrated by primitive myeloid cells with associated acute vasculitis and foci of extramedullary hematopoiesis. Subsequently, the patient was shown to have chronic myelomonocytic leukemia. Although renal involvement and vasculitis have been recorded previously in chronic myelomonocytic leukemia, this is the first occasion, to our knowledge, where their concurrence resulted in such a spectacular presentation.
Lymphoepithelioma-like Carcinoma of the Breast With Associated Sclerosing Lymphocytic Lobulitis
Authors: Naidoo P. , Chetty R.
Published: January 2021

The purpose of this article is to highlight an unusual form of breast carcinoma and discuss its differential diagnosis. A 50-year-old woman underwent wide local excision of a breast lump. Microscopic examination revealed features of a lymphoepithelioma-like carcinoma. Individual tumor cells were present within an abundant lymphoid stroma. Immunohistochemistry revealed the epithelial nature of the cells and excluded a diagnosis of lymphoma. In addition, surrounding nontumorous breast tissue displayed the histologic features of sclerosing lymphocytic lobulitis or lymphocytic mastopathy. This is the second report of a lymphoepithelioma-like carcinoma of the breast, but to the best of our knowledge, it is the first description of coexistent sclerosing lymphocytic lobulitis.
Retroperitoneal Mucinous Cystadenoma
Authors: Subramony Charu , Habibpour Saied , Hashimoto Luis A.
Published: January 2021

Primary retroperitoneal mucinous cystadenoma is an uncommon tumor found exclusively in women. Herein, we describe a patient who had resection of a large retroperitoneal cystic mass. Histologic, immunohistochemical, and electron microscopic examination of the lining epithelial cells showed features of mesothelial cells in addition to ovarian mucinous cystadenoma. These findings suggest that these tumors arise from inclusions of mesothelial cells and subsequent mucinous metaplasia of the lining cells to form a cystadenoma. Estrogen receptors may be implicated in tumor promotion, explaining the occurrence exclusively in women.
The Value of Second Opinion in Gastrointestinal and Liver Pathology
Authors: Hahm Geoffrey K. , Niemann Theodore H. , Lucas Joel G. , Frankel Wendy L.
Published: January 2021

Objective.—The value of routine second opinion review of liver and gastrointestinal pathologic material was evaluated to determine whether there were discrepancies in diagnoses and if these discrepancies had an impact on treatment or prognosis.

Materials and Methods.—All gastrointestinal and hepatobiliary histopathology referral diagnoses made during a 1-year period for patients being treated at Ohio State University Medical Center were compared with the outside pathologic diagnosis. All major discrepant diagnoses were reviewed by at least 2 pathologists. Diagnoses were classified as no diagnostic disagreement, diagnostic disagreement, or no diagnostic disagreement but pertinent information missing or terminology unclear. Discrepant cases were also classified according to the clinical significance of the discrepancy.

Results.—Pathology reports from 194 hepatobiliary and gastrointestinal cases were reviewed. Of the hepatobiliary cases, 57 (64.8%) of 88 cases showed no discrepancies. Discrepancies were noted in 31 cases (35.2%), including missing information or unclear terminology in the diagnosis in 23 cases (26.1%) and diagnostic disagreement in 8 cases (9.1%). Of the cases with discrepancies, 6 (6.8%) were of major significance. Of the gastrointestinal cases, 87 (82.1%) of 106 cases showed no discrepancies. Discrepancies were noted in 19 cases (17.9%), including missing or unclear information in 3 cases (2.8%) and diagnostic disagreements in 16 cases (15.1%). The cases with discrepancies included 8 cases (7.5%) for which the change was of major clinical significance.

Conclusions.—Routine pathologic review of gastrointestinal and hepatobiliary cases revealed notable discrepancies in diagnoses. In 14 cases (7.2%), the change in diagnosis or additional information had a significant effect on the proper treatment or a significant prognostic implication. Routine review of all pertinent pathologic material should be performed on all patients being transferred to a second institution for treatment or second opinion.
Evidence of an Inflammatory Pathologic Condition in “Normal” Appendices Following Emergency Appendectomy
Authors: Nemeth Laszlo , Reen Denis J. , O'Briain D. Sean , McDermott Michael , Puri Prem
Published: January 2021

Background.—Appendices removed from patients with suspected appendicitis often appear normal on histologic examination.

Objective.—To study appendix specimens for the expression of inflammatory markers as an indicator of presence of an inflammatory response in this subgroup of patients.

Methods.—Cyclooxygenase 1 and 2, prostaglandin E2, inducible nitric oxide synthase, and major histocompatibility complex class II were investigated by immunofluorohistochemistry using confocal laser microscopy in 15 acutely inflamed appendix specimens, 39 histologically classified “normal” appendices, and 11 negative control specimens.

Results.—Strong expressions of all the inflammatory mediators were found in the mucosa of inflamed appendices, in approximately 50% of histologically normal appendices from patients with a clinical diagnosis of appendicitis, and in none of the normal control specimens.

Conclusion.—This study confirms the existence of a subgroup of appendicitis within the so-called histologically normal appendices in which evidence of an inflammatory pathologic condition is only obvious at a molecular level. The initiating signal for this and all other forms of clinical appendicitis still remains elusive.