A machine learning algorithm improves the diagnostic accuracy of the histologic component of antibody mediated rejection (AMR-H) in cardiac transplant endomyocardial biopsies.

Background: Pathologic antibody mediated rejection (pAMR) remains a major driver of graft failure in cardiac transplant patients. The endomyocardial biopsy remains the primary diagnostic tool but presents with challenges, particularly in distinguishing the histologic component (pAMR-H) defined by 1) intravascular macrophage accumulation in capillaries and 2) activated endothelial cells that expand the cytoplasm to narrow or occlude the vascular lumen. Frequently, pAMR-H is difficult to distinguish from acute cellular rejection (ACR) and healing injury.

Distinguishing preferences of human APOBEC3A and APOBEC3B for cytosines in hairpin loops, and reflection of these preferences in APOBEC-signature cancer genome mutations.

The APOBEC3 enzymes convert cytosines in single-stranded DNA to uracils to protect against viruses and retrotransposons but can contribute to mutations that diversify tumors. To understand the mechanism of mutagenesis, we map the uracils resulting from expression of APOBEC3B or its catalytic carboxy-terminal domain (CTD) in Escherichia coli. Like APOBEC3A, the uracilomes of A3B and A3B-CTD show a preference to deaminate cytosines near transcription start sites and the lagging-strand replication templates and in hairpin loops.

Usefulness and Limitations of Current Diagnostic Strategies for Pulmonary Mucosa-Associated Lymphoid Tissue Lymphoma: Lessons Learned From a Large Cohort.

Context.—: The pathologic diagnosis of pulmonary extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is challenging.

Objective.

Distinguishing preferences of human APOBEC3A and APOBEC3B for cytosines in hairpin loops, and reflection of these preferences in APOBEC-signature cancer genome mutations.

The APOBEC3 family of enzymes convert cytosines in single-stranded DNA to uracils thereby causing mutations. These enzymes protect human cells against viruses and retrotransposons, but in many cancers they contribute to mutations that diversify the tumors and help them escape anticancer drug treatments. To understand the mechanism of mutagenesis by APOBEC3B, we expressed the complete enzyme or its catalytic carboxy-terminal domain (CTD) in repair-deficient and mapped the resulting uracils using uracil pull-down and sequencing technology.

Lymphoid Interstitial Pneumonia (LIP) Revisited: A Critical Reappraisal of the Histologic Spectrum of "Radiologic" and "Pathologic" LIP in the Context of Diffuse Benign Lymphoid Proliferations of the Lung.

The use of lymphoid interstitial pneumonia (LIP) as a diagnostic term has changed considerably since its introduction. Utilizing a multi-institutional collection of 201 cases from the last 20 years that demonstrate features associated with the LIP rubric, we compared cases meeting strict histologic criteria of LIP per American Thoracic Society (ATS)/European Respiratory Society (ERS) consensus ("pathologic LIP"; n=62) with cystic cases fulfilling radiologic ATS/ERS criteria ("radiologic LIP"; n=33) and with other diffuse benign lymphoid proliferations. "Pathologic LIP" was associated with immune dysregulation including autoimmune disorders and immune deficiency, whereas "radiologic LIP" was only seen with autoimmune disorders.

Primary Pulmonary Hyalinizing Clear Cell Carcinoma: Case Series With Review of Literature.

Hyalinizing clear cell carcinomas of tracheobronchial origin are very rare salivary gland type tumors accounting for less than 1% of lung tumors with only 13 cases reported to date. Their radiological features, morphological spectrum, and molecular features are not well described. To perform a clinicopathological analysis of primary pulmonary hyalinizing clear cell carcinomas.

Traditional risk factors and nodal yield-still relevant with high-quality risk-adapted adjuvant treatment for locally advanced head and neck cancer?

Objective: Patients with locally advanced head and neck cancer (LAHNC) often undergo multimodal therapy including radical resection of the primary tumor and neck dissection (ND) followed by risk-adapted adjuvant radio(chemo)therapy (R(C)T). Quality parameters influencing local control and survival of these patients have been postulated: resection status (R status), extranodal extension (ENE), interval to adjuvant treatment ≤6 weeks, R(C)T given when indicated, and nodal yield (NY) ≥18 lymph nodes per neck. For other solid tumors the trend is towards less extensive lymph node surgery to avoid toxicity such as lymphedema, damage to peripheral nerves, dysesthesia, or paresthesia.

Surgical Pathology of Diffuse Parenchymal Lung Disease in Patients With Psoriasis or Psoriatic Arthritis.

Context.—: Diffuse parenchymal lung disease (DPLD) is a well-recognized complication of systemic connective tissue disease (CTD) but rarely arises in patients with psoriasis or psoriatic arthritis, a poorly understood phenomenon.

Objective.

Late Complications of COVID-19.

Context.—: Studies of lungs in patients with COVID-19 have focused on early findings.

Objective.

Intraoperative central diabetes insipidus in a postpartum patient during decompression of base of brain lesion: Missing out the diagnosis of Sheehan's syndrome?

A 35-year-old female presented with headache in the third week postpartum period following uneventful cesarean delivery. She had left sided ptosis, pain, and numbness over left face since third trimester. Post-delivery magnetic resonance imaging revealed invading left sphenoid sinus meningioma.

Normal inflammatory markers in giant cell arteritis with long-standing cranial and symptomatic large-vessel involvement.

We report the case of a 78-year-old woman who presented with cardiovascular risk factors and a history of an atypical transient ischaemic attack. She was referred by her primary care physician to the vascular surgery department at our institution for evaluation of progressive weakness, fatigue, arm claudication and difficulty assessing the blood pressure in her right arm. She was being considered for surgical revascularisation, but a careful history and review of her imaging studies raised suspicion for vasculitis, despite her normal inflammatory markers.

Intraocular pressure and injection forces during intravitreal injection into enucleated porcine eyes.

Injection of biological molecules into the intravitreous humor is of increasing interest for the treatment of posterior segment eye diseases such as age-related degenerative macular degeneration. The injection volume is limited by an increase in intraocular pressure (IOP) and 50-100 µL are typically used for most intravitreally (IVT) applied commercial products. Direct measurement of IOP is difficult and has not been studied dependent on solution properties and injection rates.

Pulmonary Injury Resulting from Vaping or e-Cigarette Use: Imaging Appearances at Presentation and Follow-up.

Electronic cigarette or vaping product use-associated lung injury most frequently presents with an acute lung injury pattern at CT, manifesting as multifocal ground-glass opacity and/or consolidation, typically multifocal and multilobar, possibly with subpleural sparing. Areas of organization, manifesting as contracting consolidation, mild architectural distortion, intralobular lines, lobular distortion, and traction bronchiectasis may occur as the illness evolves. A CT appearance resembling hypersensitivity pneumonitis, reflecting the exquisitely bronchiolocentric micronodular lesions of organizing pneumonia and acute lung injury seen at histopathologic findings in these patients, may be encountered.

Radiologic and Pathologic Correlation in EVALI.

The purpose of this article is to characterize the appearance on CT of e-cigarette or vaping product use-associated lung injury (EVALI) in a cohort with histopathologic evidence of this disorder. Twenty-four patients with EVALI were identified. Chest CT examinations were reviewed by two radiologists for various chest CT findings.

Utility of Bronchoalveolar Lavage and Transbronchial Biopsy in Patients with Interstitial Lung Disease.

Purpose: Bronchoalveolar lavage and transbronchial biopsy can be a useful tool in the evaluation of interstitial lung disease (ILD), but patient selection for this procedure remains poorly defined. Determining clinical characteristics that help with patient selection for bronchoscopy may improve confidence of ILD classification while limiting potential adverse outcomes associated with surgical lung biopsy. The purpose of this study is to identify factors that were associated with change in multidisciplinary ILD diagnosis (MDD) before and after incorporation of BAL and TBBx data.

E-Cigarette or Vaping Product Use-Associated Lung Injury: A Review for Pathologists.

Context.—: Vaping is the inhalation of heated aerosol from a small battery-powered device as a method to deliver nicotine or other substances. A recent outbreak of severe respiratory illness primarily in the United States has put a spotlight on vaping and its potential risks.

Diffuse epithelioid malignant mesothelioma of the pleura presenting as a hydropneumothorax and vertebral body invasion.

Malignant mesothelioma is an uncommon form of neoplastic transformation of the mesothelial cells that line the serosal surfaces of the body. It most commonly affects the pleura and is often associated with pleural effusions and pleural-based masses. The annual incidence in the United States is only 3300 cases, representing less than 0.

CD68/CD31 immunohistochemistry double stain demonstrates increased accuracy in diagnosing pathologic antibody-mediated rejection in cardiac transplant patients.

Pathologic antibody-mediated rejection (pAMR) occurs in 10% of cardiac transplant patients and is associated with increased mortality. The endomyocardial biopsy remains the primary diagnostic tool to detect and define pAMR. However, certain challenges arise for the pathologist.

Role of FDG PET/CT in the Eighth Edition of TNM Staging of Non-Small Cell Lung Cancer.

Lung cancer is the leading cause of cancer-related mortality in the United States, and accurate staging plays a vital role in determining prognosis and treatment. The recently revised eighth edition of the TNM staging system for lung cancer defines new T and M descriptors and updates stage groupings on the basis of substantial differences in survival. There are new T descriptors that are based on the findings at histopathologic examination, and T descriptors are reassigned on the basis of tumor size and extent.

Series of rare lung diseases mimicking imaging patterns of common diffuse parenchymal lung diseases.

Diffuse parenchymal lung diseases (DPLDs) encompass a variety of restrictive and obstructive lung pathologies. In this article, the authors discuss a series of rare pulmonary entities and their high-resolution computed tomography imaging appearances, which can mimic more commonly encountered patterns of DPLDs. These cases highlight the importance of surgical lung biopsies in patients with imaging findings that do not show typical imaging features of usual interstitial pneumonia.