Larsen, Brandon T.

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. Objective.— To familiarize pathologists with vaping, the cytologic and histopathologic features of vaping-associated acute lung injury, and the role of pathology in this diagnosis. Data Sources.— A targeted literature review was performed. Conclusions.— Most cases of vaping-associated lung injury have been linked to vaping products containing tetrahydrocannabinol or other cannabinoids. Lung biopsies show a spectrum of nonspecific acute lung injury patterns (organizing pneumonia, diffuse alveolar damage, acute fibrinous, and organizing pneumonia, or combinations of the above), accompanied by prominent, foamy macrophage accumulation. Injury is usually accentuated around small airways. Lipid-laden macrophages can be identified in bronchioloalveolar lavage fluid in most patients and these can be highlighted using lipid stains, such as oil red O, but the clinical utility of this finding remains unclear, as lipid-laden macrophages can be seen in a wide variety of processes and should not be relied upon to make the diagnosis. Classic histologic features of exogenous lipoid pneumonia have not been identified in tissue samples. Lightly pigmented macrophages, similar to those seen with traditional cigarette smoking, are present in some cases but are usually a minor feature. To date, no specific pathologic features for vaping-related injury have been identified, and it remains a diagnosis of exclusion that requires clinicopathologic correlation.

Common variable immunodeficiency (CVID) and selective immunoglobulin A deficiency (IgAD) often cause chronic lung disease, but the pulmonary pathologic features of these systemic diseases are poorly recognized by pathologists. It has been claimed that CVID cases show a characteristic combination of noncaseating granulomas-lymphoid proliferations termed granulomatous-lymphocytic interstitial lung disease (GLILD). We present 34 surgical lung biopsy cases of CVID and 4 of IgAD. Noncaseating granulomas were seen in 23/34 (68%) CVID and 2/4 (50%) IgAD cases. A statistically identical pattern of benign lymphoid proliferation was found in CVID and IgAD whether or not granulomas were present. Organizing pneumonia, sometimes considered a part of GLILD, was seen in 25/34 (74%) CVID and 2/4 (50%) IgAD cases and did not correlate with the presence of granulomas. On follow-up, 3 CVID patients died (only 1 of pulmonary disease), while 21 others are alive at 1 to 300 months with no difference by presence or absence of granulomas. Three IgAD patients with follow-up are alive. We conclude that CVID and IgAD are indistinguishable in surgical lung biopsies and a subset of both show patterns that would qualify as GLILD, while other cases lack granulomas but have identical patterns of lymphoid infiltration and organizing pneumonia. We suggest that GLILD is neither a specific nor a useful entity, and biopsies from CVID and IgAD patients should be diagnosed simply by microscopic pattern(s) observed. The prognosis of CVID with lymphoid infiltrates with or without granulomas in this series was good, contrary to claims in the literature about GLILD.

Greater than 2000 cases of vaping‐associated pulmonary injury and 39 deaths reported in the United States have heightened public awareness and assumed major public health significance over recent months. Currently, knowledge of the effects of various vaping agents on the respiratory tract is in its infancy. Additional understanding of the agents implicated in these lung injuries as well as a correlation between bronchoalveolar lavage and lung biopsy samples is required.

Aims Limited data exist on atypical lipomatous tumour (ALT)/well‐differentiated liposarcoma (WDL) and de‐differentiated liposarcoma (DDLPS) in children and young adults. Methods and results Cases of ALT/WDL/DDLPS arising in patients aged ≤ 40 years were collected from multiple institutional and consultation archives. A total of 116 cases of ALT/WDL (75) and DDLPS (41) were identified, representing fewer than 5% of these tumours seen at our institutions during this time‐period. The patients (59 male/57 female) ranged in age from 8 to 40 years. Sites included deep central (abdomen/retroperitoneum/pelvis/groin) ( n = 60), extremity ( n = 42), trunk ( n = 5), head/neck ( n = 8) and mediastinum ( n = 1). De‐differentiated patterns included: high‐grade pleomorphic sarcoma, myxofibrosarcoma‐like, heterologous rhabdomyoblastic differentiation, low‐grade spindle cell sarcoma and homologous lipoblastic differentiation. Forty‐one patients experienced a local recurrence and 11 patients with DDLPS developed metastasis. ALT arising in the extremities had lower recurrence rates than deep central WDL (5‐year recurrence‐free survival 88.9% versus 59.0%; P = 0.002), while patients with deep central DDLPS experienced significantly more adverse events compared to WDL at this site (5‐year event‐free survival 11.9% versus 59.0%) ( P < 0.0001). Seven (of eight) head/neck tumours had follow‐up available; five recurred, and one patient (DDLPS) with recurrence also experienced a metastasis. The single mediastinal tumour (DDLPS) recurred and metastasised. Conclusion ALT/WDL and DDLPS occurring in patients aged ≤ 40 years is rare, but exhibits similar morphological features to its counterparts in older adults, including potential for heterologous and homologous de‐differentiation in the latter. Although case numbers are limited, tumours arising in the head and neck exhibit high rates of adverse events, suggesting that classification as WDL rather than ALT is more appropriate.

Immune checkpoint inhibitors (ICIs) have revolutionized oncology, but are associated with immune-related adverse events. Clinically, pneumonitis is a well-recognized complication, but its histopathologic features are poorly understood. Institutional archives were searched for patients having ICI therapy and subsequent lung tissue sampling. After excluding infectious cases, 9 patients (5 women, median: 59 y) were identified with clinically suspected ICI-related pneumonitis. Clinical history, imaging, and pathology slides were reviewed. Patients received pembrolizumab (6 cases), nivolumab (1), ipilimumab followed by pembrolizumab (1), or pembrolizumab followed by nivolumab (1); the latter experienced pneumonitis with both agents. Treatment duration ranged from 1 to 33 cycles (median: 8). Three patients received concurrent chemotherapy and 1 received radiation; the remainder received ICI monotherapy. Symptoms were nonspecific; 2 patients were asymptomatic. Thoracic imaging showed bilateral ground glass or nodular opacities in all cases, often with pleural effusion. Histologically, organizing pneumonia was seen in 7 patients, all with subclinical or mild disease, admixed with vague non-necrotizing airspace granulomas in 3 cases; all 6 patients with follow-up did well. One patient had acute fibrinous pneumonitis and 1 had diffuse alveolar damage; both died. All 9 cases showed foamy macrophages and pneumocyte vacuolization; 6 had rare eosinophils. ICI-related pneumonitis presents as bilateral ground-glass opacities or nodules, and usually manifests as organizing pneumonia histopathologically, often with vague non-necrotizing airspace granulomas. Foamy macrophages and pneumocyte vacuolization are characteristic and rare eosinophils are often seen. Less commonly, acute fibrinous pneumonitis or diffuse alveolar damage can occur, which may be fatal.

Tissue microarrays (TMAs) are important tools to conserve precious tissue resources from increasingly smaller biopsies and to control experimental costs and variation across sample sets. The quality assurance assessment of TMA materials created at centralized biobanks has not been standardized. Herein, we outline 2 processes for the construction of TMAs (“recipient block” and “tape” methods) and the associated preconstruction quality control measures (pathology review, protein and RNA assessment, map creation, and storage conditions) developed by the AIDS Cancer Specimen Resource (ACSR) Network’s Science and Technology Core. These steps provide a suggested framework for quality assessment that allows end-users, receiving materials from tissue banks, confidence in their experimental results.

Introduction: Takayasu arteritis is a large-vessel vasculitis that may cause oculo-cerebral ischemia. We report a patient with visual loss as initial manifestation, and discuss transcranial Doppler (TCD) findings before and after surgical revascularization. Case Description: A 19-year-old female developed episodes of transient positional right vision loss, progressing to permanent right vision loss and bright light-induced left amaurosis. Examination demonstrated subclavian bruits, palpable epigastrium aortic pulsation, faint radial pulses, right retinal pallor, arteriolar narrowing, and bilateral boxcarring. Head and neck computed tomography angiogram demonstrated left subclavian origin and right common carotid artery occlusion, and severe innominate and left common carotid artery stenosis. TCD demonstrated right ophthalmic artery flow reversal and nonpulsatile waveforms with dampened spectra in the right anterior circulation. Corticosteroids, methotrexate, infliximab, and dual-antiplatelet therapy were initiated. Eleven weeks later, the patient underwent ascending aortic aneurysm repair and bilateral carotid artery bypass with an aortic graft. Pathology was consistent with chronic active Takayasu arteritis. Two weeks postoperatively, left eye visual symptoms resolved; right visual loss persisted. Postoperative TCD showed marked improvement in cerebral perfusion. Conclusions: Retinal ischemia in young women should prompt emergent inflammatory and systemic vascular evaluation. In our subject, prolonged right retinal ischemia had dismal prognosis despite carotid-aortic revascularization, whereas left retinal boxcarring reversed. Surgical revascularization is recommended for severely symptomatic oculo-cerebrovascular disease, once inflammation is better controlled with immunosuppressive therapy. TCD documented the presence and monitored the subsequent resolution of blood flow changes causing retinal and brain hypoxia.

AbstractVerruconis gallopava is an environmental dematiaceous fungus that is recognized increasingly as a cause of human disease, especially for immunocompromised persons. Infection can range from superficial and localized lesions to pulmonary involvement and disseminated disease, including central nervous system abscesses. Optimal therapy is undefined. We report a patient post cardiac transplant who had pulmonary infection with V gallopava and was treated successfully with posaconazole.