MUC4 is a valuable marker for distinguishing secretory carcinoma of the salivary glands from its mimics.

Aims: Secretory carcinoma (SC) (synonym: mammary analogue secretory carcinoma) is a low-grade salivary gland tumour that occurs in both major and minor salivary glands. SC is known for its wide morphological, architectural and immunohistochemical spectrum, which overlaps with those of several salivary gland neoplasms, including acinic cell carcinoma (AciCC) and intercalated duct-type intraductal carcinoma (IDC) in major salivary glands, and polymorphous adenocarcinoma (PAC) in minor salivary glands. These tumours share with SC some morphological features and SOX10 immunoreactivity; also, with the exception of AciCC, they all coexpress S100 and mammaglobin.

Diagnostic value of 3D dynamic contrast-enhanced magnetic resonance imaging in lymph node metastases of head and neck tumors: a correlation study with histology.

Background: Accurate staging of cervical lymph nodes (LN) is pivotal for further clinical management of patients with head and neck cancer. Functional magnetic resonance imaging (MRI) such as three-dimensional (3D) dynamic contrast-enhanced (DCE) acquisition might improve the diagnosis of cervical LN metastases.

Purpose: To evaluate the additional diagnostic value of high-resolution 3D T1-weighted DCE in detecting LN metastasis compared to standard morphological imaging criteria in patients with head and neck tumors as correlated to histopathology.

Langerhans Cell Histiocytosis Associated With Renal Cell Carcinoma Is a Neoplastic Process: Clinicopathologic and Molecular Study of 7 Cases.

Langerhans cell histiocytosis (LCH) is a rare histiocytic disorder composed of Langerhans cells admixed with reactive mononuclear and granulocytic cells, associated with prominent eosinophils. LCH is considered a neoplasm, driven in most cases by oncogenic RAS/RAF/MEK/ERK pathway mutations. The disease predominantly affects children.

Adenomatoid Tumor of the Uterus: A Report of 6 Unusual Cases With Prominent Cysts Including 4 With Diffuse Myometrial Involvement, 4 With Uterine Serosal Involvement, and 2 Presenting in Curettage Specimens.

We evaluated the clinicopathologic features of 6 adenomatoid tumors of the uterus with unusual features. All the tumors differed grossly from the usual adenomatoid tumor, typically being ill-defined and occupying >50% of the myometrium, essentially replacing it in 4. The neoplasm extended to the endometrium in 2 cases and in one of these it formed an intracavitary mass; in both the tumor was first diagnosed in a curettage.

Genetic testing and surveillance in infantile myofibromatosis: a report from the SIOPE Host Genome Working Group.

Infantile myofibromatosis (IM), which is typically diagnosed in young children, comprises a wide clinical spectrum ranging from inconspicuous solitary soft tissue nodules to multiple disseminated tumors resulting in life-threatening complications. Familial IM follows an autosomal dominant mode of inheritance and is linked to PDGFRB germline variants. Somatic PDGFRB variants were also detected in solitary and multifocal IM lesions.

Microbiome Patterns in Matched Bile, Duodenal, Pancreatic Tumor Tissue, Drainage, and Stool Samples: Association with Preoperative Stenting and Postoperative Pancreatic Fistula Development.

Postoperative complications after pancreatic surgery are still a significant problem in clinical practice. The aim of this study was to characterize and compare the microbiomes of different body compartments (bile duct, duodenal mucosa, pancreatic tumor lesion, postoperative drainage fluid, and stool samples; preoperative and postoperative) in patients undergoing pancreatic surgery for suspected pancreatic cancer, and their association with relevant clinical factors (stent placement, pancreatic fistula, and gland texture). For this, solid (duodenal mucosa, pancreatic tumor tissue, stool) and liquid (bile, drainage fluid) biopsy samples of 10 patients were analyzed using 16s rRNA gene next-generation sequencing.

Successful BRAF/MEK inhibition in a patient with -mutated extrapancreatic acinar cell carcinoma.

Pancreatic acinar cell carcinoma (PAC) is a rare disease with a poor prognosis. Treatment options for metastatic PAC are limited and often follow chemotherapeutic regimens for pancreatic ductal adenocarcinoma. Although recurrent genomic alterations, such as fusions and defects in genes involved in homologous recombination DNA repair, have been described in PAC, data on the clinical efficacy of molecularly guided, targeted treatment are scarce.

Colorectal Adenocarcinomas Harboring ALK Fusion Genes: A Clinicopathologic and Molecular Genetic Study of 12 Cases and Review of the Literature.

This study determined the frequency and the clinicopathologic and genetic features of colorectal carcinomas driven by oncogenic fusions of the anaplastic lymphoma kinase gene (ALK). Of the 8150 screened tumors, 12 (0.15%) were immunohistochemically ALK-positive with D5F3 antibody.

Characterization of PD-1 and PD-L1 Expression in Papillary Renal Cell Carcinoma: Results of a Large Multicenter Study.

Background: Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) play a decisive role as prognostic markers in clear-cell renal cell carcinoma (RCC). To date, the role of PD-1/PD-L1 as a prognostic marker in papillary RCC (pRCC) remains scarce.

Patients And Methods: Patients' sample collection was a joint collaboration of the nationwide PANZAR consortium - a multicenter study.

Disentangling inflammatory from fibrotic disease activity by fibroblast activation protein imaging.

Objectives: To date, there is no valuable tool to assess fibrotic disease activity in humans in vivo in a non-invasive way. This study aims to uncouple inflammatory from fibrotic disease activity in fibroinflammatory diseases such as IgG-related disease.

Methods: In this cross-sectional clinical study, 27 patients with inflammatory, fibrotic and overlapping manifestations of IgG-related disease underwent positron emission tomography (PET) scanning with tracers specific for fibroblast activation protein (FAP; Ga-FAP inhibitor (FAPI)-04), F-fluorodeoxyglucose (FDG), MRI and histopathological assessment.

TERT promoter mutation analysis as a surrogate to morphology and immunohistochemistry in problematic spindle cell lesions of the urinary bladder.

Aims: Pseudosarcomatous myofibroblastic proliferations (PSMPs) of the urinary bladder are diagnostically challenging. Diagnostic difficulties are mainly due to frequent cytokeratin expression, variable ALK expression and worrisome morphological features suggestive of malignancy. Conversely, sarcomatoid urothelial carcinoma (UC) may show bland inflammatory myofibroblastic tumour (IMT)-like morphology.

Targeted sequencing of FH-deficient uterine leiomyomas reveals biallelic inactivating somatic fumarase variants and allows characterization of missense variants.

Uterine leiomyomas (ULs) constitute a considerable health burden in the general female population. The fumarate hydratase (FH) deficient subtype is found in up to 1.6% and can occur in hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome.

Recurrent Loss of SMARCA4 in Sinonasal Teratocarcinosarcoma.

Molecular analysis has reshaped the landscape of high grade sinonasal tumors by defining novel entities and identifying recurrent mutations in established tumor types. However, sinonasal teratocarcinosarcoma (TCS), a rare and aggressive tumor with intermixed teratomatous, carcinomatous, and sarcomatous elements, remains poorly understood. The multiphenotypic differentiation of TCS has engendered persistent controversy about its histogenesis and leads to diagnostic overlap with several other malignancies.

Malignant teratoid tumor of the thyroid gland: an aggressive primitive multiphenotypic malignancy showing organotypical elements and frequent DICER1 alterations-is the term "thyroblastoma" more appropriate?

Primary thyroid teratomas are exceedingly rare. Mature and immature variants recapitulate their gonadal counterparts (predilection for infants/children, triphasic germ layer differentiation, and favorable outcome). On the other hand, the so-called malignant teratomas affect predominantly adults and elderly, are highly aggressive, and, according to a few published cases, harbor DICER1 mutations.

YAP1-MAML2-Rearranged Poroid Squamous Cell Carcinoma (Squamoid Porocarcinoma) Presenting as a Primary Parotid Gland Tumor.

Porocarcinoma (synonym: malignant eccrine poroma) is a rare aggressive carcinoma type with terminal sweat gland duct differentiation. The squamous variant of porocarcinoma is even less frequent and might be indistinguishable from conventional squamous cell carcinoma (SCC). We herein describe the first case of a carcinoma presenting as a primary parotid gland malignancy in a 24-year-old male without any other primary tumor.

How Much Liver Tissue Is Required for Sufficient Histological Staging in Patients with Primary Biliary Cholangitis?

Introduction: Histological alterations in primary biliary cholangitis (PBC) are heterogeneously distributed throughout the liver. Thus, the quality of histological staging is probably dependent on the available amount of liver tissue. The goals of this study were to test this hypothesis and to define biopsy conditions for obtaining sufficient tissue.

ALK rearranged renal cell carcinoma (ALK-RCC): a multi-institutional study of twelve cases with identification of novel partner genes CLIP1, KIF5B and KIAA1217.

ALK rearranged renal cell carcinoma (ALK-RCC) has recently been included in 2016 WHO classification as a provisional entity. In this study, we describe 12 ALK-RCCs from 8 institutions, with detailed clinical, pathological, immunohistochemical (IHC), fluorescence in situ hybridization (FISH), and next generation sequencing (NGS) analyses. Patients' age ranged from 25 to 68 years (mean, 46.

YAP1-NUTM1 Gene Fusion in Porocarcinoma of the External Auditory Canal.

Gene fusions involving the NUTM1 gene (NUT) represent defining genetic markers of a highly aggressive carcinoma type with predilection for the midline structures of children and young adults, hence the original description as NUT midline carcinoma. Recent studies have increasingly documented involvement of the NUTM1 gene in the pathogenesis of other entities as well. We herein describe two cases of auditory canal carcinomas with features of porocarcinoma, both harboring a newly described YAP1-NUTM1 gene fusion.

Morphological features useful in the differential diagnosis between undifferentiated carcinoma and gastrointestinal stromal tumor.

Undifferentiated (sarcomatoid) carcinomas may closely mimic gastrointestinal stromal tumors (GISTs) due to possible histological and immunohistochemical overlap between these two entities. To avoid unnecessary employment of a wide spectrum of immunohistochemical stainings and molecular genetics and thus decrease costs, finding simple morphological features to target further investigation of such neoplasms of the gastrointestinal tract would be helpful. Five cases classified as undifferentiated (sarcomatoid) carcinomas with a definite proof of the diagnosis, i.

Aberrant Expression of Glyceraldehyde-3-Phosphate Dehydrogenase (GAPDH) in Warthin Tumors.

The Warthin tumor represents the second most frequent benign tumor of the parotid gland and is characterized by the presence of oncocytes rich in structurally and functionally altered mitochondria. Next to its role in metabolism, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is also implicated in cellular mitophagy. Immunohistochemistry was carried out on Warthin tumor and normal control (parotid gland with striated ducts) tissues, using anti-GAPDH specific antibodies followed by digital image analysis.