The American Journal of Surgical Pathology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Mesonephric-like Endometrial Carcinoma: Results From Immunohistochemical Screening of 300 Endometrial Carcinomas and Carcinosarcomas for This Often Overlooked and Potentially Aggressive Entity
Mesonephric-like endometrial carcinoma is a rare but frequently misclassified and aggressive malignancy. KRAS mutations, limited estrogen receptor (ER) expression, and TTF-1, GATA3, and luminal CD10 expression are described in these tumors, but an immunohistochemistry-based screening approach has not been studied. We assessed 300 endometrial carcinomas/carcinosarcomas to ascertain the specificity of TTF-1/GATA3/luminal CD10 expression with or without ER staining for this diagnosis. Next-generation sequencing and morphologic review were performed on screen-positive cases. In all, 3% (9/300) were TTF-1+; 2 coexpressed GATA3....
Source: The American Journal of Surgical Pathology - June 27, 2022 Category: Pathology Tags: Original Articles Source Type: research

The T Category of Distal Extrahepatic Bile Duct Carcinoma: A Comparative Analysis With Invasive Tumor Thickness
The T category of distal extrahepatic bile duct carcinoma (DBDC) is based on invasion depth from the basal lamina to the deepest infiltrating tumor cells. Recently, invasive tumor thickness (ITT) was proposed, defined as maximal vertical distance of invasive tumor components regardless of the basal lamina. We compared the predictive value of T category, and ITT grading in 424 surgically resected DBDCs. DBDCs were categorized as 6 Tis (1.4%), 134 T1 (12 mm; 18.9%). With ITT, there were 6 G0 (no invasion; 1.4%), 3 G1 ( (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - June 27, 2022 Category: Pathology Tags: Original Articles Source Type: research

SWI/SNF Complex-deficient Undifferentiated Carcinoma of the Gastrointestinal Tract: Clinicopathologic Study of 30 Cases With an Emphasis on Variable Morphology, Immune Features, and the Prognostic Significance of Different SMARCA4 and SMARCA2 Subunit Deficiencies
Undifferentiated carcinoma of the gastrointestinal tract has variable rhabdoid features. Expression of switch/sucrose nonfermenting (SWI/SNF) complex subunits is reportedly lost in a portion of cases; however, the prognostic significance of this loss remains unknown. Herein, 30 undifferentiated carcinoma cases were assessed for the expression of 4 SWI/SNF complex subunits (SMARCB1, SMARCA2, SMARCA4, and ARID1A). Tumor origin sites comprised stomach (40.0%), large intestine (20.0%), small intestine (16.7%), lower esophagus and stomach fundus (13.3%), ileocecal junction (3.3%), rectum (3.3%), and pancreas (3.3%). The tumors ...
Source: The American Journal of Surgical Pathology - June 27, 2022 Category: Pathology Tags: Original Articles Source Type: research

MYB RNA In Situ Hybridization Is a Useful Diagnostic Tool to Distinguish Breast Adenoid Cystic Carcinoma From Other Triple-negative Breast Carcinomas
Breast adenoid cystic carcinoma (AdCC) has overlapping features with basal-like triple-negative breast carcinoma (TNBC), yet carries a more favorable prognosis, and accurate diagnosis is critical. Like salivary gland AdCC, breast AdCC demonstrates recurrent alterations in the MYB gene. Novel chromogenic RNA in situ hybridization (ISH) for MYB has emerged as sensitive and specific for salivary gland AdCC. Here, we evaluate MYB RNA ISH in invasive ductal carcinomas (IDCs) including basal-like TNBC, and in the histologic mimics ductal carcinoma in situ (DCIS) and collagenous spherulosis. MYB RNA ISH was also performed on prev...
Source: The American Journal of Surgical Pathology - June 27, 2022 Category: Pathology Tags: Original Articles Source Type: research

Is it Time for a Molecular-based Classification System for Sinonasal Squamous Cell Carcinoma?
No abstract available (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - June 27, 2022 Category: Pathology Tags: Editorial Source Type: research

Diffuse Midline Gliomas With Histone H3 K27M Mutation in Adults and Children: A Retrospective Series of 164 Cases
Diffuse midline glioma, H3 K27M-mutant (H3 K27M-mt DMG), is a rare and highly aggressive tumor that is more common in children than in adults. Few studies have compared the differences between pediatric and adult patients with this rare tumor. We here report our retrospective study of 94 adult and 70 pediatric cases of diffuse midline glioma. Surgical tumor samples were analyzed by routine histopathology and immunohistochemistry for H3 K27M, IDH1 R132H, ATRX, p53, OLIG2, glial fibrillary acidic protein, and Ki-67; Sanger sequencing for hot mutation spots in genes including H3F3A, HIST1H3B, IDH1, IDH2, TERT, and BRAF; and m...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Clinicopathologic Characteristics and Prognostic Factors of Primary and Recurrent Pleomorphic Adenoma: A Single Institution Retrospective Study of 705 Cases
This study investigated the prognostic features of primary and recurrent PAs. A total of 705 PAs (613 primary and 92 recurrent) were analyzed. The following parameters: age, site and size, status of resection, histologic features, and clinical management were documented and correlated with recurrence-free survival. For primary PAs: The mean patient age was 50 years (female/male: 2/1), the median size was 2.1 cm (range: 0.5 to 9.0 cm), and the most common location was the parotid (92%). Tumors showed the following: complete encapsulation (25%), involvement of the surrounding salivary gland/fat (74%), hypercellularity (2...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Pediatric Gastrointestinal Histopathology in Patients With Tetratricopeptide Repeat Domain 7A (TTC7A) Germline Mutations: A Rare Condition Leading to Multiple Intestinal Atresias, Severe Combined Immunodeficiency, and Congenital Enteropathy
In conclusion, the unique histopathologic characteristics of TTC7A mutation-associated enteropathy described herein more fully describe this novel disease entity in infants who present with congenital enteropathy or enterocolitis. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

UHRF1 Immunohistochemical Staining Separates Benign Reactive Spindle Cell Mesothelial Proliferations From Sarcomatoid Mesotheliomas
The separation of benign from malignant mesothelial proliferations is often a difficult pathologic problem. UHRF1 (ubiquitin-like with plant homeodomain and ring finger domains-1) is a regulator of DNA methylation and an epigenetic driver of various human cancers. It has recently been reported that UHRF1 is overexpressed in mesotheliomas. We asked whether UHRF1 immunohistochemistry could be used to separate benign from malignant mesothelial proliferations. Initial studies showed that UHRF1 stained mesothelial cells but also endothelial and other non-neoplastic cells, so that accurate counting of positive mesothelial cells ...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Sinusoidal Growth Pattern of Hepatic Melanoma Metastasis: Implications for Histopathologic Diagnosis
We describe 11 metastatic melanoma cases in liver with the rare sinusoidal pattern, 3 of which were subtle and easy to miss on routine hematoxylin and eosin stain. Given that sinusoidal metastasis does not elicit a tissue reaction, it is prudent for the pathologists to be aware of this pattern of metastases and have a low threshold to order immunostains for accurate diagnosis and optimal patient care. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Recurrent Loss of Heterozygosity in Pancreatic Neuroendocrine Tumors
In this study 214 patients with grade 1, 2, or 3 pancreatic neuroendocrine tumors had their tissue examined for chromosomal copy number alterations using next-generation sequencing. Univariate and multivariate statistical analyses were performed with all-cause mortality and disease-specific mortality as the end comparators. As such, the cohort stratified into 3 different clinically relevant chromosomal subgroups: an indolent subgroup characterized by loss of chromosome 11 in relative isolation, an aggressive subgroup characterized by losses of chromosomes 1, 2, 3, 6, 10, 11, 16, and 22 and with no loss of chromosomes 4, 5,...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Metatypical Adenoid Cystic Carcinoma: A Variant Showing Prominent Squamous Differentiation With a Predilection for the Sinonasal Tract and Skull Base
Adenoid cystic carcinoma is a malignant salivary gland neoplasm, commonly involving the major and minor salivary glands. Adenoid cystic carcinoma arising in the skull base region is considerably less common and is characterized by aggressive clinical behavior, perineural invasion, and intracranial extension. Classically, these tumors are composed of ductal and myoepithelial cells, arranged as tubules and cribriform structures, as well as in a solid pattern when higher in grade. The distinctive molecular findings in this tumor are the gene fusions involving the MYB/MYBL1 and NFIB genes. Squamous differentiation, trabecular,...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

NKX6-1 Is a Less Sensitive But Specific Biomarker of Chromophobe Renal Cell Carcinoma
In conclusion, NKX6-1 may be a novel potential marker for differentiating chRCC from other renal neoplasms, especially from RO. (Source: The American Journal of Surgical Pathology)
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Hemolysis in Early Infancy: Still a Cause of Cholestatic Neonatal Giant Cell Hepatitis
Before the prophylactic use of anti-D antibodies in pregnancy, hemolytic anemia of the newborn was the most common cause of hyperbilirubinemia. Nowadays, given the rarity of hemolytic anemia of the newborn, hepatobiliary abnormalities, perinatal infections, and metabolic disorders have become the most common conditions in the differential diagnosis of neonatal cholestasis. Here, we report 3 instances of cholestatic giant cell hepatitis in 3 infants who had Coombs’ positive hemolysis due to ABO incompatibility in 1, Rh incompatibility in another, and combined ABO and Rh incompatibility in the third. Although rare, cholest...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research

Composite Classic Hodgkin Lymphoma and Follicular Lymphoma: A Clinicopathologic Study of 22 Cases With Review of 27 Additional Cases in the Literature
Composite classic Hodgkin lymphoma and follicular lymphoma (CHLFL) is a rare and poorly characterized entity. Herein, we report the clinicopathologic features of 22 cases of CHLFL from 3 institutions and we assess 27 additional cases reported in the literature. In our cohort (n=22), patients with CHLFL had a median age of 61 years and an equal male to female incidence. Most cases (95%) arose de novo with the remaining patients having a history of non-Hodgkin lymphoma. CHLFL always involved lymph nodes (100%) and most cases (95%) revealed 2 distinct areas separately diagnostic for CHL and FL. The CHL component represented a...
Source: The American Journal of Surgical Pathology - May 22, 2022 Category: Pathology Tags: Original Articles Source Type: research