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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to present with pulmonary and extra-pulmonary organ complications. In comparison with the 2009 pandemic (pH1N1), SARS-CoV-2 infection is likely to lead to more severe disease, with multi-organ effects, including cardiovascular disease. SARS-CoV-2 has been associated with acute and long-term cardiovascular disease, but the molecular changes that govern this remain unknown. In this study, we investigated the host transcriptome landscape of cardiac tissues collected at rapid autopsy from seven SARS-CoV-2, two pH1N1, and six control patients using targeted spatial transcriptomics approaches. Although SARS-CoV-2 was not detected in cardiac tissue, host transcriptomics showed upregulation of genes associated with DNA damage and repair, heat shock, and M1-like macrophage infiltration in the cardiac tissues of COVID-19 patients. The DNA damage present in the SARS-CoV-2 patient samples, were further confirmed by γ-H2Ax immunohistochemistry. In comparison, pH1N1 showed upregulation of interferon-stimulated genes, in particular interferon and complement pathways, when compared with COVID-19 patients. These data demonstrate the emergence of distinct transcriptomic profiles in cardiac tissues of SARS-CoV-2 and pH1N1 influenza infection supporting the need for a greater understanding of the effects on extra-pulmonary organs, including the cardiovascular system of COVID-19 patients, to delineate the immunopathobiology of SARS-CoV-2 infection, and long term impact on health.
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COVID-19 , Enfermedades Cardiovasculares , Humanos , SARS-CoV-2 , Transcriptoma , InterferonesRESUMEN
BACKGROUND AND OBJECTIVE: Current guidelines for the diagnosis of idiopathic pulmonary fibrosis (IPF) provide specific criteria for diagnosis in the setting of multidisciplinary discussion (MDD). We evaluate the utility and reproducibility of these diagnostic guidelines, using clinical data from the Australian IPF Registry. METHODS: All patients enrolled in the registry undergo a diagnostic review whereby international IPF guidelines are applied via a registry MDD. We investigated the clinical applicability of these guidelines with regard to: (i) adherence to guidelines, (ii) Natural history of IPF diagnostic categories and (iii) Concordance for diagnostic features. RESULTS: A total of 417 participants (69% male, 70.6 ± 8.0 years) with a clinical diagnosis of IPF underwent MDD. The 23% of participants who did not meet IPF diagnostic criteria displayed identical disease behaviour to those with confirmed IPF. Honeycombing on radiology was associated with a worse prognosis and this translated into poorer prognosis in the 'definite' IPF group. While there was moderate agreement for IPF diagnostic categories, agreement for specific radiological features, other than honeycombing, was poor. CONCLUSION: In clinical practice, physicians do not always follow IPF diagnostic guidelines. We demonstrate a cohort of IPF patients who do not meet IPF diagnostic guideline criteria, based largely on their radiology and lack of lung biopsy, but who have outcomes identical to those with IPF.
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Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Anciano , Australia , Biopsia , Estudios de Cohortes , Femenino , Adhesión a Directriz , Humanos , Fibrosis Pulmonar Idiopática/patología , Pulmón/patología , Masculino , Persona de Mediana Edad , Pronóstico , Radiografía Torácica , Sistema de Registros , Reproducibilidad de los ResultadosAsunto(s)
Linfoma de Células B Grandes Difuso/complicaciones , Linfoma de Células B Grandes Difuso/patología , Embolia Pulmonar/complicaciones , Neoplasias Vasculares/secundario , Biopsia , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Vasculares/complicaciones , Neoplasias Vasculares/patologíaRESUMEN
The nomenclature and diagnostic criteria of well-differentiated papillary mesothelial tumour (WDPMT) have been changed in the 2021 World Health Organization (WHO) classification of thoracic tumours, and a new entity, mesothelioma in situ (MIS), introduced. Histologically these two entities may be similar. However, MIS is regarded as a precursor to invasive mesothelioma and requires demonstration of loss of BAP1 and/or MTAP/CDKN2A for diagnosis, whereas performance of these ancillary tests is desirable but not essential for a diagnosis of WDPMT, in which the significance of BAP1 and/or MTAP/CDKN2A loss is not well understood or well defined. Against this backdrop, we undertook an investigation of 21 cases of WDPMT, identified from our case files and diagnosed according to 2021 WHO criteria, to explore the relationship between histology and BAP1 and MTAP/CDKN2A expression with clinical features including asbestos exposure, focality of tumours and clinical outcome. There were 18 women and three men, with ages ranging from 23-77 years (median 62 years), in which six had a history of asbestos exposure, two had no exposure, and in 13 exposure history was unavailable. Of 20 peritoneal tumours and one pleural tumour, 13 were detected incidentally at the time of surgery for unrelated conditions and eight peritoneal tumours were multifocal at the time of diagnosis. BAP1 immunohistochemistry (IHC) was performed in all 21 tumours, with nine tumours showing BAP1 expression loss. MTAP/CDKN2A testing was performed in 14 tumours, comprising MTAP IHC in 12 and CDKN2A fluorescence in situ hybridisation (FISH) in two, with three tumours showing MTAP/CDKN2A expression loss. Two tumours with MTAP/CDKN2A loss also showed BAP1 expression loss. Four patients progressed to invasive mesothelioma, including one male with a pleural tumour and asbestos exposure, and three females with multifocal peritoneal tumours, two with asbestos exposure and one without exposure. BAP1 expression loss was seen in all tumours from the four patients who progressed to invasive mesothelioma, whilst two of these tumours showed retained MTAP IHC and two were not tested. There was one patient with a tumour with MTAP loss and retained BAP1 who died from unrelated causes 5 months after diagnosis. Eight patients received WDPMT-specific treatment in addition to the initial excision. Survival for all patients ranged from 4-218 months, with one patient dying of mesothelioma at 49 months. Based on our results in this series of 21 patients with WDPMT diagnosed according to 2021 WHO criteria, we propose that WDPMT with BAP1 expression loss may best be regarded as papillary MIS and that a history of asbestos exposure and the presence of multifocal tumours in patients diagnosed with WDPMT should prompt ancillary testing with BAP1 IHC. Further we propose that BAP1 IHC should be essential in the diagnosis of WDPMT, with the diagnosis restricted to those tumours which show retained BAP1 expression. However more studies in larger cohorts of patients are needed to explore the relationship between BAP1 expression and MTAP loss in WDPMT, which will help to define this entity and separate it more clearly from MIS and invasive mesothelioma.
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Biomarcadores de Tumor , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Mesotelioma , Proteínas Supresoras de Tumor , Ubiquitina Tiolesterasa , Humanos , Ubiquitina Tiolesterasa/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Anciano , Adulto , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Mesotelioma/patología , Mesotelioma/metabolismo , Mesotelioma/diagnóstico , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/análisis , Purina-Nucleósido Fosforilasa/metabolismo , Adulto Joven , Mesotelioma Maligno/patología , Mesotelioma Maligno/diagnóstico , Mesotelioma Maligno/metabolismo , Neoplasias Mesoteliales/patología , Neoplasias Mesoteliales/metabolismo , Neoplasias Mesoteliales/diagnóstico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pleurales/patología , Neoplasias Pleurales/metabolismo , Neoplasias Pleurales/diagnóstico , InmunohistoquímicaRESUMEN
Background: Constrictive pericarditis associated with actinomycosis infection is a rare and challenging diagnosis due to its insidious manifestation. We describe the successful treatment of pericardial infiltration and constriction due to actinomycosis. Case summary: A 50-year-old Aboriginal man presented with insidious onset of fatigue, dyspnoea, pleuritic chest pain, fever, drenching sweats, severe exercise intolerance to 50â m, and recurrent itchy skin lesions over 8 months. Prior investigations, including serial fluorodeoxyglucose (FDG)-Positron emission tomography scans, found a progressively enlarging, metabolically active anterior mediastinal mass with two biopsies on separate occasions showing no malignancy, granulomas, tuberculosis, or other pathology. Screening for infective, autoimmune, and connective tissue disease was negative. A transthoracic echocardiogram (TTE) showed fibrinous pericarditis with extensive myocardial tethering and constrictive physiology confirmed on heart catheterization. A pericardial biopsy showed inflammatory tissue only. Biopsy of a skin lesion on the buttock showed abscess formation with Splendore Hoeppli phenomenon with Gram-positive and Grocott-positive filamentous bacteria suggestive of actinomyces, confirmed by 16S rRNA gene sequencing. He was diagnosed with cardiac actinomycosis, likely due to mediastinal infiltration from a lung infection, with haematogenous spread and treated with Penicillin G with adjunctive high-dose steroid therapy with resolution of symptoms and marked improvement in TTE features of constriction after 6 weeks. Discussion: Actinomycosis is an extremely rare cause of pericardial infiltration and constriction yet highly sensitive to penicillin, highlighting the importance of accurate diagnosis. Corticosteroids are a useful adjunct to prevent chronic constrictive pericarditis and to avoid the high morbidity and mortality associated with pericardiectomy.
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An investigator-initiated, Australia-wide multi-centre retrospective observational study was undertaken to investigate the real-world prevalence of programmed death ligand-1 (PD-L1) expression in non-small cell lung carcinoma (NSCLC). Multiple centres around Australia performing PD-L1 immunohistochemistry (IHC) were invited to participate. Histologically confirmed NSCLC of any stage with a PD-L1 IHC test performed for persons aged ≥18 years between 1 January 2018 and 1 January 2020, and eligible for review, were identified at each centre, followed by data extraction and de-identification, after which data were submitted to a central site for collation and analysis. In total data from 6690 eligible PD-L1 IHC tests from histologically (75%) or cytologically (24%) confirmed NSCLC of any stage were reviewed from persons with a median age of 70 years, 43% of which were female. The majority (81%) of tests were performed using the PD-L1 IHC SP263 antibody with the Ventana BenchMark Ultra platform and 19% were performed using Dako PD-L1 IHC 22C3 pharmDx assay. Reported PD-L1 tumour proportion score (TPS) was ≥50% for 30% of all tests, with 62% and 38% scoring PD-L1 ≥1% and <1%, respectively. Relative prevalence of clinicopathological features with PD-L1 scores dichotomised to <50% and ≥50%, or to <1% and ≥1%, were examined. Females scored ≥1% slightly more often than males (64% vs 61%, respectively, p=0.013). However, there was no difference between sexes or age groups (<70 or ≥70 years) where PD-L1 scored ≥50%. Specimens from patients with higher stage (III/IV) scored ≥1% or ≥50% marginally more often compared to specimens from patients with lower stage (I/II) (p≤0.002). Proportions of primary and metastatic specimens did not differ where PD-L1 TPS was ≥1%, however more metastatic samples scored TPS ≥50% than primary samples (metastatic vs primary; 34% vs 27%, p<0.001). Cytology and biopsy specimens were equally reported, at 63% of specimens, to score TPS ≥1%, whereas cytology samples scored TPS ≥50% slightly more often than biopsy samples (34% vs 30%, respectively, p=0.004). Resection specimens (16% of samples tested) were reported to score TPS ≥50% or ≥1% less often than either biopsy or cytology samples (p<0.001). There was no difference in the proportion of tests with TPS ≥1% between PD-L1 IHC assays used, however the proportion of tests scored at TPS ≥50% was marginally higher for 22C3 compared to SP263 (34% vs 29%, respectively, p<0.001). These real-world Australian data are comparable to some previously published global real-world data, with some differences noted.
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Antígeno B7-H1 , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Australia/epidemiología , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/análisis , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/metabolismo , PrevalenciaRESUMEN
The incidence of pseudotumor formation has been reported to be 1% in patients with metal-on-metal resurfacing arthroplasties. This complication is not exclusive to these patients. We report a case of pseudotumor formation secondary to femoral head-neck corrosion after a metal-on-polyethylene uncemented total hip arthroplasty.
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Artroplastia de Reemplazo de Cadera/métodos , Prótesis de Cadera/efectos adversos , Polietileno , Quiste Poplíteo/etiología , Femenino , Humanos , Persona de Mediana Edad , Diseño de PrótesisRESUMEN
Introduction: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS TBNA) is an important means of obtaining a tissue for advanced lung cancer. Optimizing the EBUS TBNA needling technique is important to maintain procedural simplicity and maximize sample quality for emerging molecular diagnostics. Methods: We prospectively explored three versus 10 agitations of the needle in sequential passes into the lymph node using separate needles. Resulting Diff-Quik cytology smears were quantitatively assessed using microscopic (tumor cell cellularity, abundance scores, erythrocyte contamination) and DNA yields. Microscopy was reported by two cytopathologists, and an inter-rater assessment was made by four additional cytopathologists. Results: In 86 patients confirmed as having malignant disease by EBUS TBNA (45 males, 41 females), a mean of 5.3 smears were made per patient with a total of 459 smears scored by pathologists and 168 paired smears extracted for DNA. There was no significant difference between three versus 10 agitations for smear cellularity (p = 0.44), DNA yield (p = 0.84), or DNA integrity (p = 0.20), but there was significantly less contamination by erythrocytes from three agitations (chi-square p = 0.008). There was significantly more DNA in the first pass into the node using three agitations than with other passes and with 10 agitations (pass × agitations interaction, p = 0.031). Reviewing pathologists correctly classified smears as more than or equal to 25% cellularity 86.3% of the time (κ = 0.63 [95% confidence interval: 0.55-0.71]). Conclusions: Three agitations are noninferior to 10 agitations for overall abundance of malignant cells and DNA content on smears. A smear with adequate DNA for panel sequencing could almost always be made with the first needle pass using three agitations.
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Diffuse malignant mesothelioma (MM) is an incurable tumour of the serosal membranes, which is often caused by exposure to asbestos and commonly diagnosed at advanced stage. Malignant mesothelioma in situ (MMIS) is now included as diagnostic category by the World Health Organization (WHO). However, our international survey of 34 pulmonary pathologists with an interest in MM diagnosis highlights inconsistency regarding how the diagnosis is being made by experts, despite published guidelines. Whilst the WHO restricts the diagnosis to surgical samples, the very concept has implication for cytological diagnosis, which is already regarded as controversial in itself by some. MMIS is currently only applicable as precursor to MM with an epithelioid component, and raises the possibility for different molecular pathways for different histological MM subtypes. The clinical implications of MMIS at this stage are uncertain, but aggressive therapies are being initiated in some instances. Based on the results of the survey we here present a critical appraisal of the concept, its clinical and conceptual implications and provide practice suggestions for diagnosis. A low threshold for ancillary testing is suggested. The designations of 'malignant mesothelioma, cannot exclude MMIS' or 'atypical mesothelial proliferation with molecular indicators of malignancy, so-called MMIS' could be used on cytology samples, adding 'no evidence of invasion in sample provided' for surgical samples. Clinical and radiological correlation are integral to diagnosis and best done at multidisciplinary meetings. Finally, collaborative studies are required to improve our understanding of MMIS.
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Mesotelioma Maligno/diagnóstico , Citodiagnóstico , Diagnóstico Precoz , Humanos , Mesotelioma Maligno/clasificación , Mesotelioma Maligno/patología , Mesotelioma Maligno/terapia , Patólogos , Membrana Serosa/patología , Encuestas y Cuestionarios , Organización Mundial de la SaludRESUMEN
We present a case of late presentation nontropical endomyocardial fibrosis isolated to the right ventricle and tricuspid valve (TV). In response to deteriorating hemodynamics, surgical debulking and TV removal were performed before initiation of centralized venoarterial extracorporeal membrane oxygenation support. Definitive endomyocardial resection with a TV prosthesis was then successfully completed. (Level of Difficulty: Advanced.).
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We report the case of a 42-year-old female with a history of finger clubbing which improved during pregnancy, a history of unexplained hepatosplenomegaly, and subsequent non-specific interstitial pneumonia with respiratory failure. Given a personal and family history of early greying of the hair, the peripheral blood monocyte telomere length was measured and was confirmed to be <1st centile, explaining the multiorgan presentation. She was treated with prednisolone, mycophenolate mofetil, and the synthetic androgen danazol with a dramatic improvement in respiratory failure and lung function. After 18 months of danazol treatment, the peripheral blood monocyte telomere length had returned to the normal range.
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BACKGROUND: Neoadjuvant immunotherapy targeting immune checkpoint programmed death-1 (PD-1) is under investigation in various tumour settings including non-small-cell lung cancer (NSCLC). Preclinical models demonstrate the superior power of the immunotherapy provided in a neoadjuvant (pre-operative) compared with an adjuvant (post-operative) setting to eradicate metastatic disease and induce long-lasting antigen-specific immunity. Novel effective immunotherapy combinations are widely sought in the oncology field, targeting non-redundant mechanisms of immune evasion. A promising combination partner with anti-PD1 in NSCLC is denosumab, a monoclonal antibody blocking receptor activator of NF-κB ligand (RANKL). In preclinical cancer models and in a large retrospective case series in NSCLC, anti-cancer activity has been reported for the combination of immune checkpoint inhibition (ICI) and denosumab. Furthermore, clinical trials of ICI and denosumab are underway in advanced melanoma and clear-cell renal cell carcinoma. However, the mechanism of action of combination anti-PD1 and anti-RANKL is poorly defined. METHODS: This open-label multicentre trial will randomise by minimisation 30 patients with resectable stage IA (primary > 2 cm) to IIIA NSCLC to a neoadjuvant treatment regime of either two doses of nivolumab (3 mg/kg every 2 weeks) or two doses of nivolumab (same regimen) plus denosumab (120 mg every 2 weeks, following nivolumab). Each treatment arm is of equal size and will be approximately balanced with respect to histology (squamous vs. non-squamous) and clinical stage (I-II vs. IIIA). All patients will receive surgery for their tumour 2 weeks after the final dose of neoadjuvant therapy. The primary outcome will be translational research to define the tumour-immune correlates of combination therapy compared with monotherapy. Key secondary outcomes will include a comparison of rates of the following between each arm: toxicity, response (pathological and radiological), and microscopically complete resection. DISCUSSION: The POPCORN study provides a unique platform for translational research to determine the mechanism of action of a novel proposed combination immunotherapy for cancer. TRIAL REGISTRATION: Prospectively registered on Australian New Zealand Clinical Trials Registry (ACTRN12618001121257) on 06/07/2018.
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Antineoplásicos Inmunológicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/terapia , Terapia Neoadyuvante/métodos , Adulto , Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Quimioterapia Adyuvante , Ensayos Clínicos Fase I como Asunto , Ensayos Clínicos Fase II como Asunto , Denosumab/farmacología , Denosumab/uso terapéutico , Femenino , Humanos , Pulmón/efectos de los fármacos , Pulmón/patología , Pulmón/cirugía , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Márgenes de Escisión , Estudios Multicéntricos como Asunto , Estadificación de Neoplasias , Nivolumab/farmacología , Nivolumab/uso terapéutico , Neumonectomía , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Supervivencia sin Progresión , Ligando RANK/antagonistas & inhibidoresRESUMEN
Purpose: Reliable and reproducible methods for identifying PD-L1 expression on tumor cells are necessary to identify responders to anti-PD-1 therapy. We tested the reproducibility of the assessment of PD-L1 expression in non-small cell lung cancer (NSCLC) tissue samples by pathologists.Experimental Design: NSCLC samples were stained with PD-L1 22C3 pharmDx kit using the Dako Autostainer Link 48 Platform. Two sample sets of 60 samples each were designed to assess inter- and intraobserver reproducibility considering two cut points for positivity: 1% or 50% of PD-L1 stained tumor cells. A randomization process was used to obtain equal distribution of PD-L1 positive and negative samples within each sample set. Ten pathologists were randomly assigned to two subgroups. Subgroup 1 analyzed all samples on two consecutive days. Subgroup 2 performed the same assessments, except they received a 1-hour training session prior to the second assessment.Results: For intraobserver reproducibility, the overall percent agreement (OPA) was 89.7% [95% confidence interval (CI), 85.7-92.6] for the 1% cut point and 91.3% (95% CI, 87.6-94.0) for the 50% cut point. For interobserver reproducibility, OPA was 84.2% (95% CI, 82.8-85.5) for the 1% cut point and 81.9% (95% CI, 80.4-83.3) for the 50% cut point, and Cohen's κ coefficients were 0.68 (95% CI, 0.65-0.71) and 0.58 (95% CI, 0.55-0.62), respectively. The training was found to have no or very little impact on intra- or interobserver reproducibility.Conclusions: Pathologists reported good reproducibility at both 1% and 50% cut points. More adapted training could potentially increase reliability, in particular for samples with PD-L1 proportion, scores around 50%. Clin Cancer Res; 23(16); 4569-77. ©2017 AACR.
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Antígeno B7-H1/análisis , Biomarcadores de Tumor/análisis , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Variaciones Dependientes del Observador , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Humanos , Inmunohistoquímica/métodos , Inmunohistoquímica/normas , Neoplasias Pulmonares/diagnóstico , Patólogos/normas , Patólogos/estadística & datos numéricos , Patología Clínica/métodos , Patología Clínica/normas , Juego de Reactivos para Diagnóstico/normas , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Patients with metastatic breast cancer often have pulmonary symptoms with varying aetiologies. Transtuzumab is an extremely important drug used in the treatment of Her 2 neu over-expressing breast cancers. In this report we describe a case of organizing pneumonia associated with use of transtuzumab in metastatic breast cancer. Only three such cases have previously been reported. CASE DESCRIPTION: A 43 year old lady with Her 2 neu 3+, estrogen and progesterone receptor positive, metastatic breast cancer was started on weekly transtuzumab and albumen bound paclitaxel. She was admitted with an episode of bilateral pneumonitis after her fourth dose of therapy. It was managed conservatively with antibiotics. Subsequently, single agent transtuzumab was administered resulting in an anaphylactoid reaction followed by worsening dyspnoea requiring hospitalization and oxygen support for 3 days. DISCUSSION AND EVALUATION: The pneumonitis warranted further investigations including bronchoscopy which were performed. Bronchoscopic biopsy was consistent with a diagnosis of organizing pneumonia. Transtuzumab was stopped and she was started on steroids (dexamethasone). She improved remarkably and was discharged home on hormonal therapy, lapatinib and tapering doses of steroids. CONCLUSION: Organizing pneumonia closely mimics infection or progressive disease and can be difficult to diagnose in the setting of malignancy. Correct diagnosis is of paramount importance since delay in treatment can result in significantly adverse patient outcomes.
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INTRODUCTION: We investigated whether a group of pathologists could reproducibly apply the International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) classification for lung adenocarcinoma to a cohort of stage 1 tumors and whether this architectural classification and/or other parameters could demonstrate survival advantage. METHODS: A total of 145 cases of 7 edition of tumor, node, metastasis stage 1 adenocarcinoma were retrospectively reviewed for predominant architectural pattern, including cribriform pattern, nuclear grade, mitotic index, and necrosis. The parameters were assessed for reproducibility and survival and using multivariate analysis, compared with stage, age, and sex. RESULTS: The majority of tumors had a mixed architecture with the acinar pattern being the most common predominant architecture. Micropapillary and cribriform architecture were the least frequent patterns. This study demonstrated that a group of five pathologists could reproducibly apply the IASLC/ATS/ERS classification. Although there were insufficient cribriform-predominant adenocarcinomas for assessment, when the percentage of all cribriform was combined with other architectures, it was associated with a worse prognosis. The majority of the parameters assessed demonstrated significance with univariate analysis but only mitotic index, as assessed by the highest count/10 high-power fields remained significant with multivariate analysis. CONCLUSION: In this study of resected stage 1 primary lung adenocarcinoma, we found mitotic index to be the only independent prognostic marker. It was more closely associated with outcome than either pathologic T stage or IASLC/ATS/ERS architecture-based classification. Further validation of concordance and reproducibility in reporting mitotic index, as well as validation of prognostic significance, needs to be undertaken in independent data sets.