The Authors Reply PMC and PMT: Real Medicine and Not Just Biology
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

PMC Versus PMT: Which Weighs More … A Pound of Rocks, or a Pound of Feathers?
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Accumulating Knowledge of EBV-positive T-Cell and NK-Cell Lymphoproliferative Diseases of Childhood
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Comparison of Systemic EBV-positive T-Cell and NK-Cell Lymphoproliferative Diseases (LPD) of Childhood Based on Classification Evolution: New Classification, Old Problems
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Nonkeratinizing Squamous Cell Carcinoma of the Sinonasal Tract With DEK-AFF2: Further Solidifying an Emerging Entity
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

NF2 Tumor Suppressor Gene Inactivation in Advanced Papillary Renal Cell Carcinoma
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

HER-2 Amplification in Uterine Serous Carcinoma and Serous Endometrial Intraepithelial Carcinoma
In conclusion, USC displays HER-2 intratumoral heterogeneity, a high IHC/FISH discordance rate, and variation in HER-2 status between the SEIC and invasive components. Caution is required when evaluating HER-2 in small biopsies, which should be repeated on excisions. Both IHC and FISH should be performed on USC until clinical trials correlate HER-2 status with clinical response to HER-2-targeted therapy. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

MHC Class I Loss in Triple-negative Breast Cancer: A Potential Barrier to PD-1/PD-L1 Checkpoint Inhibitors
Suppression of the immune system is intimately linked to the development and progression of malignancy, and immune modulating treatment options have shown promise in a variety of tumor types, including some triple-negative breast cancers (TNBC). The most dramatic therapeutic success has been seen with immune checkpoint inhibitors targeting programmed cell death protein 1 (PD-1) and its ligand, PD-L1. Difficulty remains, however, in appropriate patient selection for treatment, as many PD-L1-positive cancers fail to show durable responses to PD-1/PD-L1 inhibition. Checkpoint inhibitor targeting of the adaptive immune respons...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

EBV-positive Mucocutaneous Ulcer With Small Lymphocytic Infiltration Mimicking Nonspecific Ulceration
We report 3 cases of immunosuppressed adult patients with small lymphocytic EBV ulcers in the skin and oral mucosa, characterized by a lack of atypical lymphocytic infiltration. All 3 cases were diagnosed in routine practice. For comparisons, cases of conventional Epstein-Barr virus–positive mucocutaneous ulcer (EBVMCU) were reviewed which were extracted from our pathology archives (n=11). The present patients were 2 females and 1 male, aged above 70 years. The primary disease was rheumatoid arthritis (n=2) and dermatitis herpetiformis (n=1). The main source of immunosuppression was prednisolone (n=2) and methotrexat...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

FOS Rearrangement and Expression in Cementoblastoma
Cementoblastomas are rare odontogenic tumors developing in close proximity to the roots of teeth. Due to their striking morphologic resemblance to osteoblastomas of the peripheral skeleton, we set out to determine whether cementoblastomas harbor the same FOS rearrangements with overexpression of c-FOS as has recently been described for osteoblastomas. In total, 16 cementoblastomas were analyzed for FOS expression by immunohistochemistry and for FOS rearrangements by fluorescence in situ hybridization (FISH). We observed strong and diffuse staining of c-FOS in 71% of cementoblastomas and identified a FOS rearrangement in al...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Gastric Inverted Polyps—Distinctive Subepithelial Lesions of the Stomach: Clinicopathologic Analysis of 12 Cases With an Emphasis on Neoplastic Potential
In conclusion, GIPs are a heterogenous group showing different morphology and clinical behavior. Notably, type 1 GIP could be considered a precancerous lesion with the potential to develop adenocarcinoma. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Objective Visual Analog Scale for Biopsy Diagnosis of Helicobacter pylori Infection in Clinical Practice
This study aims to objectively investigate the density of inflammation that justifies additional workup for H. pylori infection. We retrospectively identified 2 patient cohorts who had undergone endoscopy with gastric biopsies; 1 with H. pylori infection (n=66), confirmed with a positive stool antigen test and/or Campylobacter-like organism test, and 1 without infection (n=81). Antral and body biopsies were selected from each case, if available, and stained with MUM-1 to highlight mucosal plasma cells. Digital analysis was performed to calculate the number of plasma cells/mm2, termed the “inflammatory score” (I...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Sialadenoma Papilliferum of the Bronchus: An Unrecognized Bronchial Counterpart of the Salivary Gland Tumor With Frequent: BRAF: V600E Mutations
Sialadenoma papilliferum (SP) is a rare benign tumor of the salivary glands, and only 3 unequivocal cases of SP arising in the bronchus have been reported. We herein describe the histomorphologic and molecular features of 4 bronchial SP cases and discuss the differential diagnosis of this entity and the relationship with its clinicopathologic mimics, in particular, glandular papilloma and mixed squamous cell and glandular papilloma (GP/MP). We encountered 2 male and 2 female patients with bronchial SP (mean: 66.8 y old). All 4 tumors arose in the central bronchus and were characterized by a combination of surface ex...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Pediatric Mesothelioma With ALK Fusions: A Molecular and Pathologic Study of 5 Cases
In this study, we report 5 cases of malignant mesothelioma in children, characterized by fusions involving the anaplastic lymphoma kinase (ALK) gene. Four cases occurred in females involving the abdominal cavity and were characterized by a pure epithelioid morphology. The fifth arose in the tunica vaginalis of a 15-year-old male and displayed a biphasic epithelioid-sarcomatoid phenotype. All cases demonstrated the classic morphologic and immunohistochemical features of malignant mesothelioma, including tubulopapillary architecture and cuboidal epithelioid cells with eosinophilic cytoplasm and uniform nuclei with vesicular ...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Neurofibrosarcoma Revisited: An Institutional Case Series of Uterine Sarcomas Harboring Kinase-related Fusions With Report of a Novel FGFR1-TACC1 Fusion
Uterine sarcomas with variable CD34 and S100 expression represent an emerging class of tumor in the female genital tract which commonly presents in the endocervix of premenopausal women. Initial molecular characterization identified NTRK1 and NTRK3 gene fusions as oncogenic drivers in these tumors; however, the repertoire of genetic alterations is likely more diverse given the recent discovery of PDGFB and RET gene fusions in similarly described tumors. Importantly, these fusion events lead to the aberrant activation of kinases that are potentially therapeutically targetable; therefore, recognizing this class of tumor beco...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Evaluation and Pathologic Classification of Choledochal Cysts: Clinicopathologic Analysis of 84 Cases From the West
In conclusion, diagnostic imaging guidelines used in Asia are not routinely used (but should be adopted) in the West. Pathologically, cases designated as CC are classifiable in 3 groups: category 1 (dilated native duct type), more prone to carcinomatous change; category 2, double-duct phenomenon (all but 1 being female in this study); and category 3, GI-type duplication. Overall, 17% of CCs show carcinomatous change (50% of them invasive). CC specimens should be carefully examined with this classification and submitted entirely for assessment of at-risk mucosa and cancerous transformation. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic Characterization of Epithelioid Hemangioendothelioma in a Series of 62 Cases: A Proposal of Risk Stratification and Identification of a Synaptophysin-positive Aggressive Subset
In this study, we aimed to identify clinicopathologic prognostic factors of EHE in a retrospective cohort of 62 cases with CAMTA1/TFE3/WWTR1 alterations. The tumors were of the CAMTA1 subtype for 59 cases, TFE3 subtype for 2 cases, and variant WWTR1 subtype (WWTR1-ACTL6A) for 1 case. Twenty-two tumors (35.5%) demonstrated atypical histology, defined by having at least 2 of the following 3 findings: high mitotic activity (>1/2 mm2), high nuclear grade, and coagulative necrosis. During a median follow-up of 34 months, 11 patients (18%) died, and the 5-year overall survival rate was 78.8%. Survival did not correlate...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Novel Histologic Classification of Small Tumor Cell Nests for Lung Adenocarcinoma With Prognostic and Etiological Significance: Small Solid Nests and Pure Micropapillary Nests
In conclusion, the present study has revealed 2 completely different patterns of small tumor cell nests in lung adenocarcinoma, the nonsmoking–related pMPs, and the smoking-related SSNs, by considering glandular polarity. MPP should include only pMPs, and SSNs should be in a solid pattern. This novel classification might boast clinical significance as a potent poor prognostic marker as well as a factor reflecting etiological and genetic characters. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Postmortem Findings Associated With SARS-CoV-2: Systematic Review and Meta-analysis
Coronavirus Disease 2019 (COVID-19), caused by the novel Severe Acute Respiratory Syndrome–associated Coronavirus 2 (SARS-CoV-2), has become a global threat to public health. COVID-19 is more pathogenic and infectious than the prior 2002 pandemic caused by SARS-CoV-1. The pathogenesis of certain disease manifestations in COVID-19 such as diffuse alveolar damage (DAD) are thought to be similar to SARS-CoV-1. However, the exact pathogenesis of COVID-19 related deaths remains poorly understood. The aim of this article was to systematically summarize the rapidly emerging literature regarding COVID-19 autopsies. A meta-an...
Source: The American Journal of Surgical Pathology - April 16, 2021 Category: Pathology Tags: Original Articles Source Type: research

Replacing Molecular Genetic Testing With Immunohistochemistry Using Antibodies That Recognize the Protein Products of Gene Rearrangements: “Next-generation” Immunohistochemistry
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

The SS18-SSX Antibody Has Perfect Specificity for the SS18-SSX Fusion Protein: A Validation Study of 609 Neoplasms Including 2 Unclassified Tumors With: SS18: -Non-: SSX: Fusions
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Confirmation of NKX3-1 Expression in EWSR1-NFATC2 Sarcoma and Mesenchymal Chondrosarcoma Using Monoclonal Antibody Immunohistochemistry, RT-PCR, and RNA In Situ Hybridization
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Pseudocarcinomatous Squamous Hyperplasia Involving Bone
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Jawbone Necrosis With Pseudoepitheliomatous Hyperplasia
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Letters to the Editor Source Type: research

Pulmonary Adenocarcinomas of Low Malignant Potential: Proposed Criteria to Expand the Spectrum Beyond Adenocarcinoma In Situ and Minimally Invasive Adenocarcinoma
Lung cancer screening has improved mortality among high-risk smokers but has coincidentally detected a fraction of nonprogressive adenocarcinoma historically classified as bronchoalveolar carcinoma (BAC). In the National Lung Screening Trial (NLST) the majority of BAC—comprising 29% of computed tomography–detected stage I lung adenocarcinoma—were considered overdiagnosis after extended follow-up comparison with the control arm. In the current classification, adenocarcinoma in situ and minimally invasive adenocarcinoma have replaced BAC but together comprise only ∼5% of stage I lung adenocarcinoma. Lep...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Diagnostic Accuracy of a Reduced Immunohistochemical Panel in Medulloblastoma Molecular Subtyping, Correlated to DNA-methylation Analysis
Medulloblastomas (MBs) are the most frequent childhood malignant brain tumor. Four histopathologic variants and 4 genetic subgroups have been defined in the World Health Organization (WHO) 2016 Classification and constitute major risk stratification items directly affecting the patient management. Although MB subgroups have been molecularly defined, immunohistochemical surrogates are needed. The aim of our retrospective study was to evaluate the concordance between immunohistochemistry, using 4 antibodies (YAP1, GAB1, OTX2, and β-catenin), and DNA-methylation profiling in MB subgrouping. From a series of 155 MBs, the ...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Striking Association of Lymphoid Enhancing Factor (LEF1) Overexpression and DUSP22 Rearrangements in Anaplastic Large Cell Lymphoma
Anaplastic large cell lymphomas (ALCLs) are broadly classified into ALK-positive and ALK-negative. ALK-negative ALCL is composed of DUSP22-rearranged, TP63-rearranged, and triple-negative cases. While lymphoid enhancer–binding factor (LEF1) plays a crucial role in T-cell maturation, limited data exist on its expression in T-cell lymphomas, including ALCL. We characterized the expression of LEF1 in ALCL by immunohistochemistry. LEF1 nuclear expression in the neoplastic cells was graded as negative (0), weak (1+), intermediate (2+), or strong (3+), with the percentage of LEF1-positive neoplastic cells recorded. A total...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Mesonephric (Wolffian-derived) Adenocarcinoma of the Female Urethra
In conclusion, MA, similar to those occurring in the female genital tract and distinct from the recognized Müllerian-derived carcinomas, may present primarily as urethral tumors. MA in the urethra probably shares a common pathogenesis with vaginal MA as both may originate from the same caudal loci of mesonephric remnants along the closely apposed anterior vaginal and posterior urethral walls. MA should be considered in future classifications for urethral tumors and we recommend that the confusing term “mesonephroid adenocarcinoma” should no longer be used. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Postneoadjuvant Pure and Predominantly Pure Intralymphatic Breast Carcinoma: Case Series and Literature Review
Locally advanced breast cancer is typically treated with neoadjuvant chemotherapy to decrease tumor size and optimize surgical results. Cases of pathologic complete response, are associated with favorable long-term outcomes. The American Joint Committee on Cancer (AJCC) defines pathologic complete response as a lack of residual invasive disease in the breast or lymph nodes or only residual ductal carcinoma in situ. Three studies have examined the unique pattern of postneoadjuvant pure or predominantly pure intralymphatic carcinoma. These studies are small and the prognosis associated with this disease pattern is still uncl...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clear Cell Change in Reactive Angiogenesis: A Potential Diagnostic Pitfall
Reactive angiogenesis is commonplace, occurs in many circumstances, and is important in the repair of injured tissue. Histologically, it is characterized by newly formed capillaries arranged in a lobular architecture and lined by plump endothelial cells. We have encountered a form of reactive angiogenesis not well described; composed of large endothelial cells with abundant clear cytoplasm that causes diagnostic challenges. The cohort includes 10 patients, aged 4 to 61, mean 40 years; 7 males, 3 females. One case involved bone (ilium), and 9 involved soft tissue: fingers (n=2), toes (n=2), hip joint (n=1), shoulder (n=1), ...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic and Molecular Cytogenetic Analysis of 8 Cases With Uterine Cervical Ewing Sarcoma: Case Series With Literature Review
Ewing sarcoma (ES) is a highly malignant tumor that rarely occurs in the uterine cervix. Herein, we report 8 cases with ES arising primarily in the uterine cervix by focusing on clinicopathologic and molecular cytogenetic features and differential diagnoses. Eight cases of cervical ES were diagnosed between February, 2012, and September, 2018. The age of patients ranged from 13 to 47 years. Abnormal vaginal bleeding and lower abdominal pain were the most common symptoms. Histologically, the tumor was composed of uniform, round, and oval cells with a narrow rim of eosinophilic cytoplasm. Fibrous septa were observed between ...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Distal Tubular Hyperplasia: A Proposal for a Unique Form of Renal Tubular Proliferation Distinct From Papillary Adenoma
We describe a previously uncharacterized form of renal tubular proliferation that differs from papillary adenoma (with weak or negative alpha-methylacyl-CoA racemase, lack of trisomy 7 or 17, and sometimes diffuse distribution). On the basis of consistent staining for high–molecular-weight cytokeratin and GATA3, we propose the name distal tubular hyperplasia for this process. Future studies will be helpful to assess preneoplastic potential and etiology. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

The Myoepithelial Cells of Salivary Intercalated Duct-type Intraductal Carcinoma Are Neoplastic: A Study Using Combined Whole-slide Imaging, Immunofluorescence, and: RET: Fluorescence In Situ Hybridization
Intraductal carcinoma (IDC) is a salivary gland tumor currently believed to be analogous to breast ductal carcinoma in situ, consisting of a complex neoplastic epithelial proliferation surrounded by a continuous layer of myoepithelial cells presumed to be native and non-neoplastic. Recent molecular insights have shown that there are at least 3 different types of IDC: (1) intercalated duct-like, with frequent NCOA4-RET fusions; (2) apocrine, with multiple mutations similar to salivary duct carcinoma; and (3) mixed intercalated duct-like and apocrine with frequent RET fusions, especially TRIM27-RET. Recent observations (eg, ...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic Characteristics of Mesonephric Adenocarcinomas and Mesonephric-like Adenocarcinomas in the Gynecologic Tract: A Multi-institutional Study
Mesonephric adenocarcinoma (MA) and mesonephric-like adenocarcinoma (MLA) are uncommon neoplasms of the gynecologic tract that have until recently been poorly understood. Although their morphologic, immunohistochemical, and molecular profiles have been recently defined, little is known about their clinical behavior. Small studies have demonstrated inconsistent findings and no large studies have examined the clinical behavior of these adenocarcinomas. In this multi-institutional study, representing the largest and most stringently defined cohort of cases to date, we examined the clinicopathologic features of 99 MAs and MLAs...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

MYB RNA In Situ Hybridization Facilitates Sensitive and Specific Diagnosis of Adenoid Cystic Carcinoma Regardless of Translocation Status
In this study, we sought to determine whether a novel chromogenic RNA in situ hybridization (ISH) platform could directly detect MYB RNA overexpression and offer a rapid diagnostic adjunct for AdCC. We performed MYB RNA ISH on 84 cases of AdCC as well as 128 other salivary tumors and 108 basaloid and sinonasal carcinomas that mimic AdCC. MYB RNA ISH was 92% sensitive for AdCC, including 97% of cases with MYB rearrangement and 83% without MYB rearrangement by FISH. It was also 89% specific for AdCC overall, with 95% specificity among other salivary tumors and 81% specificity in basaloid and sinonasal carcinomas. In contrast...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Predictive Patterns of Glutamine Synthetase Immunohistochemical Staining in CTNNB1-mutated Hepatocellular Adenomas
Some hepatocellular adenoma (HCA) subtypes are characterized by different CTNNB1 mutations, leading to different beta-catenin activation levels, hence variable immunostaining patterns of glutamine synthetase (GS) expression, and different risks of malignant transformation. In a retrospective multicentric study of 63 resected inflammatory (n=33) and noninflammatory (n=30) molecularly confirmed CTNNB1-mutated b-(I)HCA, we investigated the predictive potential of 3 known GS patterns as markers for CTNNB1 exon 3, 7/8 mutations. Pattern 1 (diffuse homogenous) allowed recognition of 17/21 exon 3 non-S45 mutated b-(I)HCA. Pattern...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Vasculogenic Mesenchymal Tumor: A Clinicopathologic and Molecular Study of 55 Cases of a Distinctive Neoplasm Originating From Mediastinal Yolk Sac Tumor and an Occasional Precursor to Angiosarcoma
We report 55 postchemotherapy resections of primary nonseminomatous mediastinal germ cell tumors with prominent vasculogenic features showing the formation of rudimentary to well-developed neoplastic vessels within primitive mesenchyme. These cases represented 25% of a cohort of 221 such specimens. The patients were 19 to 49 years old (mean, 28 y) and 98% had serological evidence of yolk sac tumor. The vasculogenic lesions, felt to represent a neoplastic reiteration of embryonic vasculogenesis in the splanchnic mesoderm of the yolk sac, were further subdivided into teratoma with vasculogenic stroma (n=9), vasculogen...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Contemporary Characterization and Recategorization of Adult Unclassified Renal Cell Carcinoma
Our recent study of early-onset unclassified eosinophilic renal cell carcinoma (RCC) demonstrated that two third of cases could be reclassified by performing a limited number of immunohistochemistry stains. Following the same approach, we aimed to investigate what proportion of adult unclassified RCC could be reclassified. We identified 79 cases. The mean age at presentation was 58 years (range, 29 to 84 y). Tumors were grouped based on their predominant morphologic features as oncocytic (n=23); papillary (n=22); clear cell (n=22); mucinous tubular and spindle cell (MTSC; n=5); rhabdoid (n=4); or lacking a dominant ...
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Salivary Duct Carcinoma With Rhabdoid Features—No or Aberrant Expression of E-cadherin and Genetic Changes in CDH1: Immunohistochemical and Genetic Analyses of 17 Cases
In conclusion, we propose that SDCRF is the salivary counterpart of PLCB due to its morphology and immunophenotype, and the genetic status of CDH1. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - March 19, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic Features of Chronic Intestinal Schistosomiasis and Its Distinction From Crohn Disease
Chronic intestinal schistosomiasis (CIS) can mimic chronic colitis of other etiologies, particularly inflammatory bowel disease. Recognizing clinical and pathologic features unique to schistosomiasis can facilitate differential diagnosis. Clinical, endoscopic, imaging, macroscopic, and histologic features of 40 CIS cases were reviewed and compared with 40 cases of Crohn disease (CD). The most common symptoms of CIS were abdominal pain, distention, bloody stool, weight loss, and anemia. Lesions were mainly located in the rectum and/or left colon in 67.5% of patients. Polyps were seen colonoscopically in 57.1% and yellow gra...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Molecularly Classified Uterine FIGO Grade 3 Endometrioid Carcinomas Show Distinctive Clinical Outcomes But Overlapping Morphologic Features
FIGO grade 3 endometrioid endometrial carcinoma (EEC) is a heterogenous group of tumors with variable molecular and clinicopathologic characteristics but is treated clinically as a single entity. There is a need for additional objective markers to help guide management. The aim of this study was to evaluate a cohort of FIGO grade 3 EEC to validate the prognostic impact of molecular classification using POLE mutation (POLE-mut) analysis and immunohistochemistry for p53 and mismatch repair proteins. A secondary aim was to assess for any morphologic or immunophenotypic correlates among the molecular groups. Ninety-five cases ...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

SMARCA4/SMARCA2-deficient Carcinoma of the Esophagus and Gastroesophageal Junction
We present the first series of undifferentiated carcinoma of the esophagus and gastroesophageal junction with this characteristic morphology associated with loss of SMARCA4 and/or SMARCA2 expression. This tumor type likely arises from dedifferentiation of a lower grade carcinoma in some cases, and Barrett esophagus and appears to be associated with an aggressive clinical course. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Masson Trichrome and Sulfated Alcian Blue Stains Distinguish Light Chain Deposition Disease From Amyloidosis in the Lung
Light chain deposition disease, characterized by nonamyloidogenic deposits of immunoglobulin light chains, is rare in the lung and possibly underdiagnosed due to low clinical suspicion and lack of readily accessible tests. We encountered a case of pulmonary light chain deposition disease (PLCDD) in which light chain deposits appeared crimson red with a Masson trichrome (MT) stain and salmon pink with a sulfated Alcian blue (SAB) stain. This prompted us to characterize a series of PLCDD cases and assess the utility of MT and SAB stains to distinguish them from amyloidosis. From the pathology archives of 2 institutions spann...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

A Critical Assessment of Postneoadjuvant Therapy Pancreatic Cancer Regression Grading Schemes With a Proposal for a Novel Approach
Currently, there is no consensus on the optimal tumor response score (TRS) system to assess regression in pancreatic cancers resected after neoadjuvant therapy. We developed a novel TRS (Royal North Shore [RNS] system) based on estimating the percentage of tumor bed occupied by viable cancer and categorized into 3 tiers: grade 1 (≤10%), grade 2 (11% to 75%), and grade 3 (>75%). We assessed 147 resected carcinomas with this and other TRS systems (College of American Pathologists [CAP], MD Anderson Cancer Center [MDACC], and Evans). The 3-tiered RNS system predicted median survival after surgery for grades 1, 2, and 3 ...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Biomarkers for Risk Stratification in Patients With Previously Untreated Follicular Lymphoma Receiving Anti–CD20-based Biological Therapy
Follicular lymphoma (FL) is an indolent B-cell neoplasm of germinal center origin. Standard treatment regimens consist of anti-CD20 therapy with or without chemotherapy. While high response rates to initial therapy are common, patients ultimately relapse or have progressive disease. Clinical risk factors such as the Follicular Lymphoma International Prognostic Index (FLIPI) have been identified, but there is a need for prognostic and predictive biomarkers. We studied markers of lymphoma cells and tumor microenvironment by immunohistochemistry in tissue samples from patients enrolled in 1 of 4 phase 2 trials of anti–C...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Mixed Endometrioid Adenocarcinoma and Müllerian Adenosarcoma of the Uterus and Ovary: Clinicopathologic Characterization With Emphasis on its Distinction From Carcinosarcoma
Mullerian adenosarcoma is a biphasic neoplasm composed of benign or atypical Müllerian epithelium and a malignant mesenchymal component that is usually, but not always, of low grade. Focal architectural or cytologic atypia of the epithelial component resembling atypical hyperplasia may uncommonly be present and foci of adenocarcinoma have been rarely reported. Whether the coexistence of these 2 tumor components is a result of independent primaries (collision tumor), adenocarcinoma arising from the epithelial component of the adenosarcoma, an unusual form of carcinosarcoma or some other mechanism is uncertain. To estab...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic Features and Diagnostic Implications of Pyloric Gland Metaplasia in Intestinal Specimens
Pyloric gland metaplasia (PGM) is a histopathologic change usually seen after inflammatory injury and, although described in association with inflammatory bowel disease (IBD) and particularly Crohn disease (CD), its significance is still debated. We evaluated long-term correlates of PGM in a large cohort of 601 intestinal specimens, 227 (37.8%) biopsies, and 374 (62.2%) resections, from 567 different patients, 328 (57.8%) male and 239 (42.2%) female, with a mean age of 43.4±15.8 years. During mean clinical follow-up of 83.5±48.1 months, 511 (90.1%) patients were diagnosed with IBD, 457 (89.4%) with CD, and 53...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

A Diagnostic Approach to the Identification of Burkitt-like Lymphoma With 11q Aberration in Aggressive B-Cell Lymphomas
Rare cases of aggressive B-cell lymphomas with a morphology similar to Burkitt lymphoma (BL) present with the BL-typical immunophenotype, but lacked MYC translocation (MYC-negative Burkitt-like lymphoma: mnBLL). A proportion of those with an imbalance pattern in chromosome 11q has been designated Burkitt-like lymphoma with 11q aberration in the recent update of the World Health Organization (WHO) classification. Because of the problems in the identification of Burkitt-like lymphoma with 11q aberration, our goal was to retrospectively analyze their frequency in a cohort of “candidate” aggressive lymphomas (cohor...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

ALK-positive Histiocytosis of the Breast: A Clinicopathologic Study Highlighting Spindle Cell Histology
In this study, we report 3 cases of ALK-positive histiocytosis of the breast. The patients were Asian women, aged 16 to 45 years. Two patients presented with an isolated breast mass, while 1 exhibited multiorgan involvement. The latter patient received ALK inhibitor after surgery, which led to complete remission. Histologically, well-circumscribed tumors displayed fascicular and storiform growth of uniform, nonatypical spindle cells admixed with lymphocytic infiltrates. Fewer conventional epithelioid histiocytes with lobulated or clefted nuclei were observed within the same breast tumors in 2 cases or within a concomitant ...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research

Aberrant GATA3 Staining in Prostatic Adenocarcinoma: A Potential Diagnostic Pitfall
Distinguishing between poorly differentiated urothelial carcinoma and high-grade prostatic adenocarcinoma is a common challenge in genitourinary pathology, particularly when the tumor involves the bladder neck or prostatic urethra. Clinically, the distinction between these 2 tumors can also be difficult. Proper diagnosis in these patients is essential as they have differing prognoses and clinical management. GATA3 is thought to be a sensitive and relatively specific marker of urothelial carcinoma. However, there is scant data regarding GATA3 labeling of high-grade prostatic adenocarcinoma. The aim of this study is to descr...
Source: The American Journal of Surgical Pathology - February 18, 2021 Category: Pathology Tags: Original Articles Source Type: research