Analysis of ASCL1/NEUROD1/POU2F3/YAP1 Yields Novel Insights for the Diagnosis of Olfactory Neuroblastoma and Identifies Sinonasal Tuft Cell-Like Carcinoma.

The diagnosis and treatment of sinonasal small round epithelial/neuroepithelial malignancies depend on the expression of conventional neuroendocrine markers (NEMs), such as synaptophysin, chromogranin A, INSM1, and CD56/NCAM1. However, these tumors remain diagnostically challenging because of overlapping histologic and immunohistochemical features. The transcriptional regulators ASCL1, NEUROD1, POU2F3, and YAP1 are novel NEM (nNEM) used for the subtyping of small-cell lung cancer (SCLC).

The Complexity of Tobacco Smoke-Induced Mutagenesis in Head and Neck Cancer.

Tobacco smoke, alone or combined with alcohol, is the predominant cause of head and neck cancer (HNC). Here, we further explore how tobacco exposure contributes to cancer development by mutational signature analysis of 265 whole-genome sequenced HNC from eight countries. Six tobacco-associated mutational signatures were detected, including some not previously reported.

The Mutographs biorepository: A unique genomic resource to study cancer around the world.

Large-scale biorepositories and databases are essential to generate equitable, effective, and sustainable advances in cancer prevention, early detection, cancer therapy, cancer care, and surveillance. The Mutographs project has created a large genomic dataset and biorepository of over 7,800 cancer cases from 30 countries across five continents with extensive demographic, lifestyle, environmental, and clinical information. Whole-genome sequencing is being finalized for over 4,000 cases, with the primary goal of understanding the causes of cancer at eight anatomic sites.

TIROSEC: Molecular, Clinical and Histopathological Profile of Papillary Thyroid Carcinoma in a Colombian Cohort.

Introduction: In Colombia, thyroid cancer ranks among the highest incidences, yet our population lacks studies on its molecular profile. This study aims to characterize clinical, histopathologic and molecular data in a Colombian cohort with papillary thyroid carcinoma (PTC).

Methods: A retrospective review of clinical history, clinicopathologic characteristics, treatment and 5-10-year follow-up for all patients was done.

Prevalence of SARS-CoV-2 infection and SARS-CoV-2-specific antibody detection among healthcare workers and hospital staff of a university hospital in Colombia.

Objective: The aim of this study was to determine current and previous SARS-COV-2 infection, and describe risk factors associated with seropositivity, among HCWs and hospital staff between June and October of 2020.

Methodology: Data from the day of enrollment for a prospective cohort study were analyzed to determine point prevalence and seroprevalence of SARS-CoV-2 infection in HCWs and hospital staff of a university hospital in Colombia. Respiratory samples were collected to perform RT-PCR tests, along with blood samples to measure SARS-CoV-2 IgM and IgG antibodies.

Biomarkers of human papillomavirus (HPV)-driven head and neck cancer in Latin America and Europe study: Study design and HPV DNA/p16 status.

Background: Human papillomavirus (HPV)-driven head/neck squamous cell carcinomas (HNSCC) prevalence varies globally. We evaluated HPV DNA and p16 in formalin fixed paraffin embedded (FFPE) HNSCC from Argentina, Brazil, Colombia, and Peru.

Methods: HPV was genotyped by PCR-hybridization.

Carcinoma of the rete testis: A rare testicular tumor.

Carcinoma of the rete testis is a rare malignant tumor which frequently occurs in middle-aged to older patients and has an aggressive biological behavior. We present the case of a 57-year-old man who presented with an ill-defined mass in the right testicle. The patient underwent a radical orchidectomy.

Predictors of Survival After Head and Neck Squamous Cell Carcinoma in South America: The InterCHANGE Study.

Purpose: Head and neck squamous cell carcinoma (HNSCC) incidence is high in South America, where recent data on survival are sparse. We investigated the main predictors of HNSCC survival in Brazil, Argentina, Uruguay, and Colombia.

Methods: Sociodemographic and lifestyle information was obtained from standardized interviews, and clinicopathologic data were extracted from medical records and pathologic reports.

Helicobacter pylori culture as a key tool for diagnosis in Colombia.

Introduction: The presence of H. pylori in the stomach is associated with gastric pathologies. However, its diagnosis through culture methods is challenging because of its complex nutritional requirements and microaerophilic conditions for optimal growth.

Epithelioid hemangioendothelioma of the parotid gland: A case report in an unusual location with a review of the literature.

Epithelioid hemangioendothelioma (EHE) is a malignant vascular tumor that usually affects the liver, lung, bone and deep soft tissues of the extremities or trunk. To our knowledge, only 3 cases in the parotid gland have been reported to date. We report a case of a 62-year-old woman who presented with a 1-year history of a slow-growing, painless mass over the left mandibular angle.

Esophageal tuberculosis in an HIV-positive patient mimicking a spindle cell tumor.

Tuberculosis (TB) of the esophagus is an extremely rare condition, even in immunocompromised patients. We report the case of a 24-year-old man with a past history of HIV and pulmonary tuberculosis who presented with dysphagia and a 2cm submucosal mass in the proximal esophagus. The biopsy was diagnosed as a spindle cell neoplasm in another center.

Advantage of Z-stacking for teleconsultation between the USA and Colombia.

Introduction: There is an emerging need for telecytology in Colombia as the demand for cytopathology has increased. However, due to economic and technological constraints telecytology services are limited. Our aim was to evaluate the diagnostic feasibility of using whole slide imaging with and without Z-stacking for telecytology in Colombia, South America.

Malignant Solitary Fibrous Tumor of the Humerus: A Case Report of an Extremely Rare Primary Bone Tumor.

Solitary fibrous tumor (SFT) is a spindle-shaped cell neoplasm originally described in the pleura, but subsequently found in many anatomic sites. Only few cases of primary SFTs in the bone have been previously described in the literature. We present the case of an 86-year-old man with a 1-week history of pain in his left arm.

Esophageal Pyogenic Granuloma: A Case Report and Review of the Literature.

Pyogenic granuloma (PG) is a capillary hemangioma mainly found in the skin and oral mucosa, but rarely described in the esophagus. We report the case of a 66-year-old man who consulted for retrosternal pain. Endoscopic studies showed a 28-mm polypoid mass located at the distal esophageal mucosa.

Evaluation of Helicobacter pylori Infection and Clarithromycin Resistance in Strains From Symptomatic Colombian Children.

The aim of the study was to determine the current prevalence of Helicobacter pylori in symptomatic Colombian children and evaluate the presence of mutations associated with clarithromycin resistance. Biopsies from 133 children were analyzed. The gastric fragment was used for urease test and reused for polymerase chain reaction sequencing of the 23SrDNA gene.

Accuracy and interobserver agreement of retroareolar frozen sections in nipple-sparing mastectomies.

In the last decades, surgical treatment of breast cancer has enormously changed. As a result, nipple-sparing mastectomy (NSM) has evolved as an oncologically safe and cosmetic approach. NSM includes a subareolar frozen section to evaluate malignancy.

Proximal-Type Epithelioid Sarcoma: Report of an Unusual Case in the Uterine Cervix.

Epithelioid sarcoma is a rare malignant mesenchymal neoplasm (less than 1% of all sarcomas) with epithelioid morphology. Among the 2 subtypes, proximal represents only one-third of cases and commonly involves deep tissues of pelvic region, including the perineum, genital area, and groin, and occurs more frequently in older patients who present a more aggressive course. In the female genital tract, proximal-type epithelioid sarcoma (PES) mainly affects the vulva and is extremely uncommon in the uterus.

Cytologic findings of mammary analogue secretory carcinoma arising in the thyroid.

Mammary analogue secretory carcinoma (MASC) of the salivary gland, first described by Skálová et al in 2010, is a tumor that morphologically and genetically resembles breast secretory carcinoma harboring ETV6-NTRK3 fusion gene. To date, only seven cases of primary thyroid MASC have been described. The overall findings are similar to those seen in the salivary gland counterpart including the ETV6-NTRK3 fusion gene.

Endometriosis mimicking glandular atypia in a cervical cytology.

Endometriosis involving the uterine cervix is a rare condition that can lead to diagnostic errors in the interpretation of Pap smear. We report the case of a 41-year-old patient in whom the initial Pap smear revealed three-dimensional clusters of glandular cells with elongated nuclei, occasional mitosis, and atypia, which was interpreted as atypical glandular cells, not otherwise specified (NOS). The patient was taken to colposcopy and endocervical biopsy.

Co-expressed miRNAs in gastric adenocarcinoma.

Co-expression networks may provide insights into the patterns of molecular interactions that underlie cellular processes. To obtain a better understanding of miRNA expression patterns in gastric adenocarcinoma and to provide markers that can be associated with histopathological findings, we performed weighted gene correlation network analysis (WGCNA) and compare it with a supervised analysis. Integrative analysis of target predictions and miRNA expression profiles in gastric cancer samples was also performed.

Unusual morphology of desmoplastic small round cell tumor from an ascitic fluid in the postchemotherapy setting.

Desmoplastic small round cell tumor (DSRCT) is a malignant neoplasm that most often presents in male adolescents as an abdominal mass. Cytological features have been previously described, but only two reports noted post chemotherapy changes on effusions. We report a case of a 15-year-old male with DSRCT status postchemotherapy that presented with ascitis.

Hepatocellular carcinoma with both fibrolamellar and classical components: an unusual morphological pattern.

Fibrolamellar carcinoma (FLC) is an uncommon form of primary liver malignancy with unique clinical, histological, and biological characteristics. It is usually seen in young adults without underlying liver disease. Histologically, it shows large cells with abundant eosinophilic cytoplasm, large vesicular nuclei, prominent nucleoli, and lamellar type fibrosis.

The "drunken honeycomb" feature of pulmonary mucinous adenocarcinoma: a diagnostic pitfall of bronchial brushing cytology.

Pulmonary mucinous adenocarcinoma (PMA) is the terminology recently proposed in the new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) International Multidisciplinary Classification of Lung Adenocarcinoma Guidelines for most tumors previously classified as mucinous bronchioloalveolar carcinomas (mBACs). PMA is histologically characterized by lepidic growth and at least some degree of invasive growth of goblet or columnar neoplastic cells with abundant intracytoplasmic mucin. We report here the cytologic features of PMA in a bronchial brushing specimen.