Distant metastasis from morphologically low-grade spiradenocarcinoma: A report of two cases.

Malignant tumors arising from benign eccrine spiradenomas are rare. They are divided by morphology into low-grade and high-grade spiradenocarcinomas, with prognosis and metastatic potential closely linked to their histopathologic features. Tumors with low-grade morphology are known for their indolent behavior, with only two reported instances of metastatic spread. We report herein two further low-grade metastatic spiradenocarcinomas resulting in distant metastasis. Both tumors showed a background of a benign spiradenoma and subtle histopathologic signs of malignant transformation, characterized by loss of the dual-cell population, up to moderate cytological atypia and increased mitotic activity. Both patients developed metastases to the lungs years after the initial presentation, and one showed additional lymph nodal disease. We show that even the morphologically low-grade tumors may rarely show more aggressive behavior. Although often challenging, recognition of the morphologically low-grade malignant spiradenocarcinoma and long-term follow-up of the patients are important to detect metastatic disease.

Historical shift in pathological type of progressive massive fibrosis among coal miners in the USA.

BACKGROUND: Pneumoconiosis among coal miners in the USA has been resurgent over the past two decades, despite modern dust controls and regulatory standards. Previously published studies have suggested that respirable crystalline silica (RCS) is a contributor to this disease resurgence. However, evidence has been primarily indirect, in the form of radiographic features. METHODS: We obtained lung tissue specimens and data from the National Coal Workers' Autopsy Study. We evaluated specimens for the presence of progressive massive fibrosis (PMF) and used histopathological classifications to type these specimens into coal-type, mixed-type and silica-type PMF. Rates of each were compared by birth cohort. Logistic regression was used to assess demographic and mining characteristics associated with silica-type PMF. RESULTS: Of 322 cases found to have PMF, study pathologists characterised 138 (43%) as coal-type, 129 (40%) as mixed-type and 55 (17%) as silica-type PMF. Among earlier birth cohorts, coal-type and mixed-type PMF were more common than silica-type PMF, but their rates declined in later birth cohorts. In contrast, the rate of silica-type PMF did not decline in cases from more recent birth cohorts. More recent year of birth was significantly associated with silica-type PMF. CONCLUSIONS: Our findings demonstrate a shift in PMF types among US coal miners, from a predominance of coal- and mixed-type PMF to a more commonly encountered silica-type PMF. These results are further evidence of the prominent role of RCS in the pathogenesis of pneumoconiosis among contemporary US coal miners.

Evidence for Environmental-Human Microbiota Transfer at a Manufacturing Facility with Novel Work-related Respiratory Disease.

Rationale: Workers' exposure to metalworking fluid (MWF) has been associated with respiratory disease.Objectives: As part of a public health investigation of a manufacturing facility, we performed a cross-sectional study using paired environmental and human sampling to evaluate the cross-pollination of microbes between the environment and the host and possible effects on lung pathology present among workers.Methods: Workplace environmental microbiota were evaluated in air and MWF samples. Human microbiota were evaluated in lung tissue samples from workers with respiratory symptoms found to have lymphocytic bronchiolitis and alveolar ductitis with B-cell follicles and emphysema, in lung tissue samples from control subjects, and in skin, nasal, and oral samples from 302 workers from different areas of the facility. In vitro effects of MWF exposure on murine B cells were assessed.Measurements and Main Results: An increased similarity of microbial composition was found between MWF samples and lung tissue samples of case workers compared with control subjects. Among workers in different locations within the facility, those that worked in the machine shop area had skin, nasal, and oral microbiota more closely related to the microbiota present in the MWF samples. Lung samples from four index cases and skin and nasal samples from workers in the machine shop area were enriched with Pseudomonas, the dominant taxa in MWF. Exposure to used MWF stimulated murine B-cell proliferation in vitro, a hallmark cell subtype found in the pathology of index cases.Conclusions: Evaluation of a manufacturing facility with a cluster of workers with respiratory disease supports cross-pollination of microbes from MWF to humans and suggests the potential for exposure to these microbes to be a health hazard.

Severe lung disease characterized by lymphocytic bronchiolitis, alveolar ductitis, and emphysema (BADE) in industrial machine-manufacturing workers.

BACKGROUND: A cluster of severe lung disease occurred at a manufacturing facility making industrial machines. We aimed to describe disease features and workplace exposures. METHODS: Clinical, functional, radiologic, and histopathologic features were characterized. Airborne concentrations of thoracic aerosol, metalworking fluid, endotoxin, metals, and volatile organic compounds were measured. Facility airflow was assessed using tracer gas. Process fluids were examined using culture, polymerase chain reaction, and 16S ribosomal RNA sequencing. RESULTS: Five previously healthy male never-smokers, ages 27 to 50, developed chest symptoms from 1995 to 2012 while working in the facility's production areas. Patients had an insidious onset of cough, wheeze, and exertional dyspnea; airflow obstruction (mean FEV1 = 44% predicted) and reduced diffusing capacity (mean = 53% predicted); and radiologic centrilobular emphysema. Lung tissue demonstrated a unique pattern of bronchiolitis and alveolar ductitis with B-cell follicles lacking germinal centers, and significant emphysema for never-smokers. All had chronic dyspnea, three had a progressive functional decline, and one underwent lung transplantation. Patients reported no unusual nonoccupational exposures. No cases were identified among nonproduction workers or in the community. Endotoxin concentrations were elevated in two air samples; otherwise, exposures were below occupational limits. Air flowed from areas where machining occurred to other production areas. Metalworking fluid primarily grew Pseudomonas pseudoalcaligenes and lacked mycobacterial DNA, but 16S analysis revealed more complex bacterial communities. CONCLUSION: This cluster indicates a previously unrecognized occupational lung disease of yet uncertain etiology that should be considered in manufacturing workers (particularly never-smokers) with airflow obstruction and centrilobular emphysema. Investigation of additional cases in other settings could clarify the cause and guide prevention.

Squamous intraepithelial lesions in cervical tissue samples of limited adequacy and insufficient for grading as low or high grade: outcome, clinico-pathological correlates, and predictive role of p16INK4a and Ki67 biomarker staining.

OBJECTIVE: Cervical tissue samples of limited adequacy but with pathological features of squamous intraepithelial lesions (SIL) may not be gradable and result in a diagnosis of ungraded SIL (SILQ). SILQ outcome, clinico-pathological correlates, and the predictive role of biomarker staining are unknown. MATERIALS AND METHODS: Among 17,551 colposcopy attendees, 478 (2.7%) had SILQ. Glass slides of 472 were reviewed. Positive [high SIL (HSIL), adenocarcinoma in situ (AIS), or carcinoma] and negative [negative for intraepithelial lesion or malignancy (NILM) or low SIL (LSIL)] outcomes were based on the worst pathology in 24 months of follow-up. p16 and Ki67 immunohistochemistry of 80 random SILQ and 149 controls (44 NILM, 15 LSIL, 75 HSIL, and 15 AIS) was scored as unsatisfactory, positive, or negative. Biomarker and outcome status were correlated, and sensitivity, specificity positive predictive value (PPV), and negative predictive value (NPV) were calculated. RESULTS: Of the total cases, 332 (1.9%) were reviewed as SILQ, and follow-up for 329 was positive in 134 (41%). Atypical glandular cells, AIS, atypical squamous cells (cannot exclude HSIL), HSIL referral Pap test (70% vs. 47%, p < .001), and HSIL colposcopic impression (33% vs. 19%, p < .001) were more frequent among positive compared with negative outcomes. Best SILQ sensitivity (89%) and NPV (77%) occurred with combined biomarkers, and best specificity (52%) and PPV (58%) occurred with Ki67. All 4 performance metrics among the controls were high. CONCLUSIONS: The 2% frequency and 41% positive outcome highlight the clinical importance of SILQ. The referral Pap test and colposcopic impression could prioritize follow-up colposcopy for some SILQ, and negative staining with both biomarkers could eliminate further colposcopy in others.

Characterizing Lung Particulates Using Quantitative Microscopy in Coal Miners With Severe Pneumoconiosis.

CONTEXT.­: Current approaches for characterizing retained lung dust using pathologists' qualitative assessment or scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) have limitations. OBJECTIVE.­: To explore polarized light microscopy coupled with image-processing software, termed quantitative microscopy-particulate matter (QM-PM), as a tool to characterize in situ dust in lung tissue of US coal miners with progressive massive fibrosis. DESIGN.­: We developed a standardized protocol using microscopy images to characterize the in situ burden of birefringent crystalline silica/silicate particles (mineral density) and carbonaceous particles (pigment fraction). Mineral density and pigment fraction were compared with pathologists' qualitative assessments and SEM/EDS analyses. Particle features were compared between historical (born before 1930) and contemporary coal miners, who likely had different exposures following changes in mining technology. RESULTS.­: Lung tissue samples from 85 coal miners (62 historical and 23 contemporary) and 10 healthy controls were analyzed using QM-PM. Mineral density and pigment fraction measurements with QM-PM were comparable to consensus pathologists' scoring and SEM/EDS analyses. Contemporary miners had greater mineral density than historical miners (186 456 versus 63 727/mm3; P = .02) and controls (4542/mm3), consistent with higher amounts of silica/silicate dust. Contemporary and historical miners had similar particle sizes (median area, 1.00 versus 1.14 µm2; P = .46) and birefringence under polarized light (median grayscale brightness: 80.9 versus 87.6; P = .29). CONCLUSIONS.­: QM-PM reliably characterizes in situ silica/silicate and carbonaceous particles in a reproducible, automated, accessible, and time/cost/labor-efficient manner, and shows promise as a tool for understanding occupational lung pathology and targeting exposure controls.

Pathologic Findings in Severe Coal Workers' Pneumoconiosis in Contemporary US Coal Miners.

CONTEXT.­: The pathology of coal workers' pneumoconiosis (CWP) and its most severe form-progressive massive fibrosis (PMF)-in US coal miners has changed in recent years. Severe disease is occurring in younger miners and has been linked to an increase in silica dust exposure. OBJECTIVE.­: To update the description of the pathologic features of CWP in contemporary miners compared to historical miners. DESIGN.­: This study is a retrospective expert classification of lung tissue from 85 historical and contemporary coal miners with PMF. Significant pathologic features were scored by using a standardized instrument with consensus achieved for major findings, including newly defined categories of PMF as coal-type, mixed-type, and silica-type. RESULTS.­: Pathologic features associated with silica dust exposure, including silica-type PMF, mineral dust alveolar proteinosis (MDAP), and immature (early stage) silicotic nodules were increased in contemporary miners. Detailed descriptions of the pathology of contemporary CWP with illustrative figures are provided. CONCLUSIONS.­: Silica-related pathologies are more common in contemporary miners. Severe forms of CWP can be detected by subtyping PMF lesions (if present) or by identification of mature and immature silicotic nodules, coal mine dust-related alveolar proteinosis, and severe inflammation in coal miners' lungs. Silica-type PMF cases showed significantly higher levels of MDAP than either mixed- or coal-type PMF (P < .001). High profusion of birefringent silica/silicate particles was observed more frequently in cases with immature (early stage) silicotic nodules (P = .04). Severe inflammation was also significantly increased in contemporary miners (P = .03). Our findings underscore the urgent need to revise current exposure limits and monitoring of respirable crystalline silica in US coal mines.

Mining Tenure and Job Duties Differ Among Contemporary and Historic Underground Coal Miners With Progressive Massive Fibrosis.

OBJECTIVE: To characterize differences in mining jobs and tenure between contemporary (born 1930+, working primarily with modern mining technologies) and historic coal miners with progressive massive fibrosis (PMF). METHODS: We classified jobs as designated occupations (DOs) and non-DOs based on regulatory sampling requirements. Demographic, occupational characteristics, and histopathological PMF type were compared between groups. RESULTS: Contemporary miners ( n = 33) had significantly shorter mean total (30.4 years vs 37.1 years, P = 0.0006) and underground (28.8 years vs 35.8 years, P = 0.001) mining tenure compared with historic miners ( n = 289). Silica-type PMF was significantly more common among miners in non-DOs (30.1% vs 15.8%, P = 0.03) and contemporary miners (58.1% vs 15.2%, P < 0.0001). CONCLUSIONS: Primary jobs changed over time with the introduction of modern mining technologies and likely changed exposures for workers. Elevated crystalline silica exposures are likely in non-DOs and require attention.

Prolonged SARS-CoV-2 infection following rituximab treatment: clinical course and response to therapeutic interventions correlated with quantitative viral cultures and cycle threshold values.

BACKGROUND: Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA is completed through reverse transcriptase-PCR (RT-PCR) from either oropharyngeal or nasopharyngeal swabs, critically important for diagnostics but also from an infection control lens. Recent studies have suggested that COVID-19 patients can demonstrate prolonged viral shedding with immunosuppression as a key risk factor. CASE PRESENTATION: We present a case of an immunocompromised patient with SARS-CoV-2 infection demonstrating prolonged infectious viral shedding for 189 days with virus cultivability and clinical relapse with an identical strain based on whole genome sequencing, requiring a multi-modal therapeutic approach. We correlated clinical parameters, PCR cycle thresholds and viral culture until eventual resolution. CONCLUSIONS: We successfully demonstrate resolution of viral shedding, administration of COVID-19 vaccination and maintenance of viral clearance. This case highlights implications in the immunosuppressed patient towards infection prevention and control that should consider those with prolonged viral shedding and may require ancillary testing to fully elucidate viral activity. Furthermore, this case raises several stimulating questions around complex COVID-19 patients around the role of steroids, effect of antiviral therapies in absence of B-cells, role for vaccination and the requirement of a multi-modal approach to eventually have successful clearance of the virus.

Pathology and Mineralogy Demonstrate Respirable Crystalline Silica Is a Major Cause of Severe Pneumoconiosis in U.S. Coal Miners.

Rationale: The reasons for resurgent coal workers' pneumoconiosis and its most severe forms, rapidly progressive pneumoconiosis and progressive massive fibrosis (PMF), in the United States are not yet fully understood. Objectives: To compare the pathologic and mineralogic features of contemporary coal miners with severe pneumoconiosis with those of their historical counterparts. Methods: Lung pathology specimens from 85 coal miners with PMF were included for evaluation and analysis. We compared the proportion of cases with pathologic and mineralogic findings in miners born between 1910 and 1930 (historical) with those in miners born in or after 1930 (contemporary). Results: We found a significantly higher proportion of silica-type PMF (57% vs. 18%; P < 0.001) among contemporary miners compared with their historical counterparts. Mineral dust alveolar proteinosis was also more common in contemporary miners compared with their historical counterparts (70% vs. 37%; P < 0.01). In situ mineralogic analysis showed that the percentage (26.1% vs. 17.8%; P < 0.01) and concentration (47.3 × 108 vs. 25.8 × 108 particles/cm3; P = 0.036) of silica particles were significantly greater in specimens from contemporary miners compared with their historical counterparts. The concentration of silica particles was significantly greater when silica-type PMF, mineral dust alveolar proteinosis, silicotic nodules, or immature silicotic nodules were present (P < 0.05). Conclusions: Exposure to respirable crystalline silica appears causal in the unexpected surge of severe disease in contemporary miners. Our findings underscore the importance of controlling workplace silica exposure to prevent the disabling and untreatable adverse health effects afflicting U.S. coal miners.

Clinicopathological determinants of vaginal and premalignant-malignant cervico-vaginal polyps of the lower female genital tract.

OBJECTIVE: To establish pathology frequencies for polyps in the vagina and cervix and to identify determinants of vaginal polyps and premalignant-malignant cervico-vaginal polyps. MATERIALS AND METHODS: The pathology reports of all cervico-vaginal polyps examined for 6 years at a single institution were classified, and frequencies were calculated. In 2 separate case-control studies, clinical and pathological variables of vaginal cases were compared with cervical controls, and premalignant-malignant cases were compared with benign controls. Differences in variables that were abstracted from patients' chart and pathology reviews were tested for significance. RESULTS: There were 4,402 polyps; 4,340 cervical (98.6%), 62 vaginal (1.4%), 4,268 benign (97.0%), 62 premalignant-malignant (1.4%) (CIN, endometrial hyperplasia, and carcinoma), and 72 unsatisfactory (1.6%). Age was a significant determinant of vaginal and premalignant-malignant polyps, and polyp size and number were significant determinants of vaginal polyps. Vaginal polyps were 3 times more frequent among women 40 years and younger and twice as frequent among those 60 years and older (p < .001). Premalignant-malignant polyps were twice as frequent among women 40 years and younger (p = .04), and malignant polyps were 6 times more frequent in those 60 years and older, which approached statistical significance (p = .09). Multiple polyps were 2 times more frequent (p = .04) and greater than 2 cm was 4 times (p = .01) more frequent among vaginal polyps. CONCLUSIONS: Vaginal polyps and premalignant-malignant cervico-vaginal polyps are rare. Vaginal polyps are larger and multiple and cervico-vaginal polyps in younger and older women are at greater risk of premalignant-malignant changes.

WT1 immunoprofiling and comparison of malignant Mullerian mixed tumors of the female genital tract.

A malignant Mullerian mixed tumor (MMMT) is a biphasic homologous or heterologous malignancy of the female genital tract. WT1 (Wilms tumor 1) is both a tumor suppressor gene and oncogene overexpressed in the nuclei of some gynecologic carcinomas. Expression in MMMT is incompletely described. Whole sections from 16 MMMTs were stained with WT1 (N terminus) using a standard immunoperoxidase technique. There were 7 heterologous and 9 homologous tumors and 10 were endometrial, 5 were ovarian, and 1 was of peritoneal origin. The tissue and cell staining pattern and score (intensity by amount) were evaluated and correlated with the tumor subtype and anatomic location. Among the 16 tumors, 81.3% showed mostly stromal and cytoplasmic staining and a score of 3 or 6. Staining was positive in 80% of the endometrial and ovarian tumors and the 1 peritoneal tumor and in all heterologous and 66.7% of the homologous tumors. The immunoprofile correlated with tumor subtype but not with anatomic location. Stromal and epithelial staining was more frequent (83.3%) in homologous tumors and differed significantly (P=0.009) from the heterologous types where stromal staining prevailed (85.7%). MMMT is another genital tract malignancy which can over express WT1 and the immunoprofile may assist in tumor subtyping.

Multidrug-resistant Aeromonas hydrophila causing fatal bilateral necrotizing fasciitis in an immunocompromised patient: a case report.

BACKGROUND: Aeromonas hydrophila is a water-dwelling, gram-negative rod-shaped bacterium, associated with diarrheal illness and, less commonly, necrotizing skin and soft tissue infections, especially among immunocompromised patients. Necrotizing fasciitis is associated with a high mortality rate, especially when caused by Aeromonas spp. Our patient was infected with an extremely aggressive form of multidrug-resistant Aeromonas spp. that produced both an extended-spectrum ß-lactamase and an AmpC enzyme. Aeromonads are being recognized as important emerging pathogens because of their inherent antibiotic resistance profiles compounded by other virulence factors. These difficult-to-treat organisms can have significant implications in both clinical and public health settings. CASE PRESENTATION: A 37-year-old Caucasian male with immunosuppression due to aplastic anemia being treated with cyclosporine, presented to hospital with relapsed disease. While in hospital, he subsequently developed overwhelming sepsis secondary to bilateral lower extremity necrotizing fasciitis. The necrotizing fasciitis was caused by a multidrug-resistant strain of A. hydrophila. Despite broad-spectrum antibiotics and aggressive surgical debridement, he succumbed to this severe invasive infection. CONCLUSIONS: Necrotizing fasciitis caused by Aeromonas spp. is a rare infection that may have a poor clinical outcome, particularly if the diagnosis is delayed and/or the organism is highly virulent and multidrug resistant. Enhanced education of clinicians and microbiologists is required to prevent unnecessary complications and improve survival.

Multiple Thromboembolic Events from a Left Atrial Appendage Occlusion Device.

Left atrial appendage occlusion devices are an alternative to oral anticoagulation in patients with nonvalvular atrial fibrillation who are at risk of ischemic stroke. Thromboprophylaxis after implantation is recommended, but the optimal regimen is unknown. We report a clinicopathologic case in which thrombus adherent to an incompletely endothelialized WATCHMAN device (Boston Scientific, Marlborough, MA) resulted in multiple thromboembolic events, contributing to a fatal outcome. This case illustrates uncertainties regarding the device's endothelialization process.

Tumour thrombus of the inferior vena cava extending into the right atrium in the setting of colon cancer.

Tumour thrombus is seen in renal cell and hepatocellular carcinoma, but is rarely reported in colorectal cancer. A woman aged 46 years, with metastatic colonic adenocarcinoma, was found to have a large mass in the inferior vena cava (IVC) extending into the right atrium. Although this lesion was initially thought to be bland thrombus, imaging with contrast-enhanced CT scan and contrast-enhanced ultrasound supported the diagnosis of tumour thrombus. Despite the large size of the lesion, the patient was asymptomatic. Her lack of symptoms, and poor overall prognosis from her cancer led to the decision to avoid aggressive surgical or radiological interventions. Several months later, the patient passed away. At autopsy, there was no evidence of fatal embolisation from the pre-existing thrombus. Diagnosis of tumour thrombus in the IVC is difficult and management can be challenging due to the significant risks associated with treatment options.

Underrecognition of pathologist contributions to articles published in a major multidisciplinary medical journal.

The Canadian Medical Association Journal (CMAJ) is a high-impact multidisciplinary medical journal. We have observed instances in which a pathology diagnosis, documented with gross or microscopic images, forms an integral part of a CMAJ article, but a pathologist is neither an author nor acknowledged as a contributor. To examine the hypothesis that pathologist contributions are underrecognized and/or underdocumented, we reviewed all CMAJ articles over a 6-year period (September 2003-2009), and correlated the use of pathology images with pathologist authorship or contribution. For each article containing pathology images, department affiliations of authors were determined, and acknowledgments were assessed. Although only 1.7% of articles contained pathology images, 47% (26/55) of these articles did not include a pathologist as either an author or a contributor. We conclude that important intellectual contributions of pathologists are underrecognized and suggest that the scientific credibility of pathology data is in doubt when pathologists do not take on full responsibility of authorship or are not acknowledged as contributors.