Endoscopic follow-up of low-grade precancerous bronchial lesions in high-risk patients: long-term results of the SELEPREBB randomised multicentre trial.

BACKGROUND: 3-9% of low-grade preinvasive bronchial lesions progress to cancer. This study assessed the usefulness of an intensive bronchoscopy surveillance strategy in patients with bronchial lesions up to moderate squamous dysplasia. METHODS: SELEPREBB (ClinicalTrials.gov NCT00213603) was a randomised study conducted in 17 French centres. After baseline lung computed tomography (CT) and autofluorescence bronchoscopy (AFB) to exclude lung cancer and bronchial severe squamous dysplasia or carcinoma in situ (CIS), patients were assigned to standard surveillance (arm A) with CT and AFB at 36 months or to intensive surveillance (arm B) with AFB every 6 months. Further long-term data were obtained with a median follow-up of 4.7 years. RESULTS: 364 patients were randomised (A: 180, B: 184). 27 patients developed invasive lung cancer and two developed persistent CIS during the study, with no difference between arms (OR 0.63, 95% CI 0.20-1.96, p=0.42). Mild or moderate dysplasia at baseline bronchoscopy was a significant lung cancer risk factor both at 3 years (8 of 74 patients, OR 6.9, 95% CI 2.5-18.9, p<0.001) and at maximum follow-up (16 of 74 patients, OR 5.9, 95% CI 2.9-12.0, p<0.001). Smoking cessation was significantly associated with clearance of bronchial dysplasia on follow-up (OR 0.12, 95% CI 0.01-0.66, p=0.005) and with a reduced risk of lung cancer at 5 years (OR 0.15, 95% CI 0.003-0.99, p=0.04). CONCLUSION: Patients with mild or moderate dysplasia are at very high risk for lung cancer at 5 years, with smoking cessation significantly reducing the risk. Whereas intensive bronchoscopy surveillance does not improve patient outcomes, the identification of bronchial dysplasia using initial bronchoscopy maybe useful for risk stratification strategies in lung cancer screening programmes.

Vascular Ehlers-Danlos syndrome (vEDS): CT and histologic findings of pleural and lung parenchymal damage.

OBJECTIVES: To describe CT features of lung involvement in patients with vascular Ehlers-Danlos syndrome (vEDS), a rare genetic condition caused by pathogenic variants within the COL3A1 gene, characterized by recurrent arterial, digestive, and pulmonary events. MATERIAL AND METHODS: All consecutive vEDS patients referred to the national tertiary referral center for vEDS, between 2004 and 2016, were included. Chest CT scans obtained during the initial vascular work-up were reviewed retrospectively by two chest radiologists for lung involvement. Five surgical samples underwent histologic examination. RESULTS: Among 136 enrolled patients (83 women, 53 men; mean age 37 years) with molecularly confirmed vEDS, 24 (17.6%) had a history of respiratory events: 17 with pneumothorax, 4 with hemothorax, and 3 with hemoptysis that required thoracic surgery in 11. CT scans detected lung parenchymal abnormalities in 78 (57.3%) patients: emphysema (mostly centrilobular and paraseptal) in 44 (32.3%), comparable for smokers and non-smokers; clusters of calcified small pulmonary nodules in 9 (6.6%); and cavitated nodules in 4 (2.9%). Histologic examination of surgical samples found arterial abnormalities, emphysema with alveolar ruptures in 3, accompanied by diffuse hemorrhage and increased hemosiderin resorption. CONCLUSION: In vEDS patients, identification of lung parenchymal abnormalities is common on CT. The most frequently observed CT finding was emphysema suggesting alveolar wall rupture which might facilitate the diagnostic screening of the disease in asymptomatic carriers of a genetic COL3A1 gene mutation. The prognostic value and evolution of these parenchymal abnormalities remain to be evaluated. KEY POINTS: • Patients with vEDS can have lung parenchymal changes on top of or next to thoracal vascular abnormalities and that these changes can be present in asymptomatic cases. • The presence of these parenchymal changes is associated with a slightly higher incidence of respiratory events (although not statistically significant). • Identification of the described CT pattern by radiologists and chest physicians may facilitate diagnostic screening.

In situ BCL2 expression is an independent prognostic factor in HIV-associated DLBCL, a LYMPHOVIR cohort study.

The prognostic value of cell of origin (COO) classification and BCL2 expression is not well established in diffuse large B-cell lymphoma (DLBCL) patients with human immunodeficiency virus (HIV) infection in the recent era. Phenotypic patterns were determined by immunohistochemistry (IHC) of pathological samples from patients with HIV-associated DLBCL prospectively enrolled in the French AIDS and Viral Hepatitis CO16 Lymphovir cohort between 2008 and 2015. Molecular subgroup classification into germinal centre B-cell (GCB) and non-GCB subtypes was determined using the Hans algorithm. Among 52 samples of systemic DLBCL subjected to centralized pathological analysis, 25 of the 42 tested for BCL2 expression were positive. Samples were further classified into GCB (n = 19) and non-GCB (n = 16) subtypes and 17 remained unclassified. In multivariable analysis, BCL2 expression was an independent pejorative prognostic biomarker [4-year progression-free survival (PFS): 52% for BCL2+ vs. 88% for BCL2- , P = 0·02] and tended to reduce 4-year overall survival (OS) (63% for BCL2+ vs. 88% for BCL2- , P = 0·06). The difference between CGB and non-GCB subtypes on PFS and OS did not reach significance (4-year PFS: 79% for GCB vs. 53% for non-GCB, P = 0·24 and 4-year OS: 78% for GCB vs. 69% for non-GCB, P = 0·34). BCL2 expression determined by IHC is an independent pejorative prognostic biomarker in HIV-associated DLBCL in the recent era. This supports the investigation of new therapeutic strategies in patients with BCL2 expression.

Semantic Integrative Digital Pathology: Insights into Microsemiological Semantics and Image Analysis Scalability.

Being able to provide a traceable and dynamic second opinion has become an ethical priority for patients and health care professionals in modern computer-aided medicine. In this perspective, a semantic cognitive virtual microscopy approach has been recently initiated, the MICO project, by focusing on cognitive digital pathology. This approach supports the elaboration of pathology-compliant daily protocols dedicated to breast cancer grading, in particular mitotic counts and nuclear atypia. A proof of concept has thus been elaborated, and an extension of these approaches is now underway in a collaborative digital pathology framework, the FlexMIm project. As important milestones on the way to routine digital pathology, a series of pioneer international benchmarking initiatives have been launched for mitosis detection (MITOS), nuclear atypia grading (MITOS-ATYPIA) and glandular structure detection (GlaS), some of the fundamental grading components in diagnosis and prognosis. These initiatives allow envisaging a consolidated validation referential database for digital pathology in the very near future. This reference database will need coordinated efforts from all major teams working in this area worldwide, and it will certainly represent a critical bottleneck for the acceptance of all future imaging modules in clinical practice. In line with recent advances in molecular imaging and genetics, keeping the microscopic modality at the core of future digital systems in pathology is fundamental to insure the acceptance of these new technologies, as well as for a deeper systemic, structured comprehension of the pathologies. After all, at the scale of routine whole-slide imaging (WSI; ∼0.22 µm/pixel), the microscopic image represents a structured 'genomic cluster', enabling a naturally structured support for integrative digital pathology approaches. In order to accelerate and structure the integration of this heterogeneous information, a major effort is and will continue to be devoted to morphological microsemiology (microscopic morphology semantics). Besides insuring the traceability of the results (second opinion) and supporting the orchestration of high-content image analysis modules, the role of semantics will be crucial for the correlation between digital pathology and noninvasive medical imaging modalities. In addition, semantics has an important role in modelling the links between traditional microscopy and recent label-free technologies. The massive amount of visual data is challenging and represents a characteristic intrinsic to digital pathology. The design of an operational integrative microscopy framework needs to focus on scalable multiscale imaging formalism. In this sense, we prospectively consider some of the most recent scalable methodologies adapted to digital pathology as marked point processes for nuclear atypia and point-set mathematical morphology for architecture grading. To orchestrate this scalable framework, semantics-based WSI management (analysis, exploration, indexing, retrieval and report generation support) represents an important means towards approaches to integrating big data into biomedicine. This insight reflects our vision through an instantiation of essential bricks of this type of architecture. The generic approach introduced here is applicable to a number of challenges related to molecular imaging, high-content image management and, more generally, bioinformatics.

Liver biopsy analysis has a low level of performance for diagnosis of intermediate stages of fibrosis.

BACKGROUND & AIMS: There is controversy about the performance of noninvasive tests such as FibroTest in diagnosing intermediate stages of fibrosis. We investigated whether this controversy results from limitations of biopsy analysis for intermediate-stage fibrosis and inappropriate determination of the standard area under the receiver-operator characteristic curve (AUROC). METHODS: To determine whether biopsy has a lower diagnostic performance for fibrosis stage F2 (few septa) vs F1 (fibrosis without septa), compared with its performance for F1 vs F0 or F4 vs F3, we determined the fibrotic areas of large surgical samples collected from 20 consecutive patients with chronic liver disease or normal liver tissue that surrounded tumors. We analyzed digitized images of 27,869 virtual biopsies of increasing length and also analyzed data from 6500 patients with interpretable FibroTest results who also underwent biopsy analysis. RESULTS: The overall performance of biopsy analysis (by Obuchowski measure) increased with biopsy length from 0.885 for 5-mm to 0.912 for 30-mm samples (P < .0001). The performance of biopsy was lower for the diagnosis of F2 vs F1 samples (weighted AUROC [wAUROC] = 0.505) than for F1 vs F0 (wAUROC = 0.773; 53% difference; P < .0001) or F4 vs F3 (wAUROC = 0.700; 39% difference; P < .0001), even when 30-mm biopsy samples were used. The performance of FibroTest was also lower for the diagnosis of F2 vs F1 samples (wAUROC = 0.512) than for F1 vs F0 samples (wAUROC = 0.626; 22% difference; P < .0001) or F4 vs F3 (wAUROC = 0.628; 23% difference; P < .0001). However, the FibroTest had smaller percentage differences among wAUROC values than biopsy. CONCLUSIONS: Biopsy has a low level of diagnostic performance for fibrosis stages F2 and F1. The recommendation for biopsy analysis, instead of a validated biomarker panel such as FibroTest, for the diagnosis of intermediate stages of fibrosis is therefore misleading.

Pulmonary involvement in Erdheim-Chester disease: a single-center study of thirty-four patients and a review of the literature.

OBJECTIVE: Erdheim-Chester disease (ECD) is a rare form of non-Langerhans' cell histiocytosis that may present with pulmonary involvement. We undertook the current study to evaluate the characteristic features of pulmonary involvement in ECD, in the largest single-center series of patients reported to date. METHODS: We performed a retrospective study of the characteristics of 34 consecutive patients with biopsy-proven ECD who were referred to the internal medicine department of Pitié-Salpêtrière Hospital between 1981 and November 2008. RESULTS: Data were obtained from 23 men and 11 women. The median age at the time of diagnosis was 53.7 years (range 16-73 years), and the median followup was 3.5 years (1.4-5.3 years). Eight patients (24%) had pulmonary symptoms. High-resolution computed tomography (HRCT) scans of the chest revealed involvement of lung parenchyma in 18 patients (53%) and of the pleura in 14 patients (41%). Bronchoalveolar lavage fluid analysis revealed the presence of an opalescent aspirate in all the patients studied. Treatment with corticosteroids and/or interferon-α (IFNα) resulted in a marked improvement of the pulmonary lesions in only a single patient. Comparison of the survival between patients with and those without pulmonary involvement yielded no significant difference between the groups (P = 0.82). CONCLUSION: Pulmonary involvement in ECD has been overlooked in previous studies. HRCT reveals typical lesions in most patients. There is no clear response of these lesions to corticosteroids and IFNα. The overall prognosis of the disease is poor, but pulmonary involvement does not appear to be a major prognostic factor in ECD.

Comprehensive Molecular and Pathologic Evaluation of Transitional Mesothelioma Assisted by Deep Learning Approach: A Multi-Institutional Study of the International Mesothelioma Panel from the MESOPATH Reference Center.

INTRODUCTION: Histologic subtypes of malignant pleural mesothelioma are a major prognostic indicator and decision denominator for all therapeutic strategies. In an ambiguous case, a rare transitional mesothelioma (TM) pattern may be diagnosed by pathologists either as epithelioid mesothelioma (EM), biphasic mesothelioma (BM), or sarcomatoid mesothelioma (SM). This study aimed to better characterize the TM subtype from a histological, immunohistochemical, and molecular standpoint. Deep learning of pathologic slides was applied to this cohort. METHODS: A random selection of 49 representative digitalized sections from surgical biopsies of TM was reviewed by 16 panelists. We evaluated BAP1 expression and CDKN2A (p16) homozygous deletion. We conducted a comprehensive, integrated, transcriptomic analysis. An unsupervised deep learning algorithm was trained to classify tumors. RESULTS: The 16 panelists recorded 784 diagnoses on the 49 cases. Even though a Kappa value of 0.42 is moderate, the presence of a TM component was diagnosed in 51%. In 49% of the histological evaluation, the reviewers classified the lesion as EM in 53%, SM in 33%, or BM in 14%. Median survival was 6.7 months. Loss of BAP1 observed in 44% was less frequent in TM than in EM and BM. p16 homozygous deletion was higher in TM (73%), followed by BM (63%) and SM (46%). RNA sequencing unsupervised clustering analysis revealed that TM grouped together and were closer to SM than to EM. Deep learning analysis achieved 94% accuracy for TM identification. CONCLUSION: These results revealed that the TM pattern should be classified as non-EM or at minimum as a subgroup of the SM type.

Msx and dlx homeogene expression in epithelial odontogenic tumors.

Epithelial odontogenic tumors are rare jaw pathologies that raise clinical diagnosis and prognosis dilemmas notably between ameloblastomas and clear cell odontogenic carcinomas (CCOCs). In line with previous studies, the molecular determinants of tooth development-amelogenin, Msx1, Msx2, Dlx2, Dlx3, Bmp2, and Bmp4-were analyzed by RT-PCR, ISH, and immunolabeling in 12 recurrent ameloblastomas and in one case of CCOC. Although Msx1 expression imitates normal cell differentiation in these tumors, other genes showed a distinct pattern depending on the type of tumor and the tissue involved. In benign ameloblastomas, ISH localized Dlx3 transcripts and inconstantly detected Msx2 transcripts in epithelial cells. In the CCOC, ISH established a lack of both Dlx3 and Msx2 transcripts but allowed identification of the antisense transcript of Msx1, which imitates the same scheme of distribution between mesenchyme and epithelium as in the cup stage of tooth development. Furthermore, while exploring the expression pattern of signal molecules by RT-PCR, Bmp2 was shown to be completely inactivated in the CCOC and irregularly noticeable in ameloblastomas. Bmp4 was always expressed in all the tumors. Based on the established roles of Msx and Dlx transcription factors in dental cell fates, these data suggest that their altered expression is a proposed trail to explain the genesis and/or the progression of odontogenic tumors.

Fluorescence diagnosis and flat lesions of urothelium: new challenges for pathologists and urologists (Review).

Bladder cancer is a common malignancy. Recurrence rate and progression vary greatly depending on factors such as tumor multiplicity, size, previous recurrence rates, tumor stage, tumor grade and the presence of carcinoma in situ. Treatment is expensive, recent studies demonstrated that superficial bladder cancer is a major economic burden. It is necessary to establish new kinds of techniques to improve diagnosis, therapy and follow-up, such as fluorescence diagnosis, without adding significant risk of complications. As urologists have a better sight of bladder lesions with fluorescence diagnosis, pathologists will be asked in the future to evaluate more frequently flat lesions, which up to now would not have been a matter of concern. For several reasons it is very important to have accurate and precise definitions of these flat lesions. First to permit uniform treatment of large groups of patients and second to see in large cohorts the evolution and natural history of several flat lesions, not always well known up to now. The aim of the study was to review the most important flat lesions, to demonstrate the difficulty of classifying several lesions, to introduce to urologists the new problems linked to FD and to suggest new models for accurate analysis. How far can we go in our answer as pathologists and how will it change the patient management?

Aurora-A/STK-15 is differentially expressed in the micropapillary variant of bladder cancer.

INTRODUCTION: Micropapillary carcinoma (MPC) of the bladder is a rare and aggressive histologic variant of urothelial carcinoma (UC). At the time of presentation, most MPC are muscle invasive with frequent vascular invasion (VI). Our series explores protein expression of markers known to be indicators of poor clinical outcome and progression, trying to explain aggressiveness of MPC. PATIENTS AND METHODS: 18 patients with MPC were reviewed. We explored protein expression of p53, MIB-1, Aurora-A and survivin in MPC and compared their expression to conventional urothelial carcinoma (CUC) of the same grade and stage. RESULTS: Patients, aged 46-85 years, underwent transurethral resection or cystoprostatectomy for UC. MPC was either pure (39%) or only partially present (61%). 55% of the patients died. VI was seen in 95%. MPC displayed overexpression of p53 and MIB-1, Aurora-A and survivin. No statistically significant difference could be made with CUC except for Aurora-A (p = 0.03). CONCLUSIONS: This is the first study to explore different markers of bad clinical outcome in MPC. We suggest that Aurora-A via mechanisms implied into early steps of mitosis might play a role in aggressive clinical behavior of MPC.

Pulmonary veno-occlusive disease: clinical, functional, radiologic, and hemodynamic characteristics and outcome of 24 cases confirmed by histology.

Pulmonary veno-occlusive disease (PVOD) is defined by specific pathologic changes of the pulmonary veins. A definite diagnosis of PVOD thus requires a lung biopsy or pathologic examination of pulmonary explants or postmortem lung samples. However, lung biopsy is hazardous in patients with severe pulmonary hypertension, and there is a need for noninvasive diagnostic tools in this patient population. Patients with PVOD may be refractory to pulmonary arterial hypertension (PAH)-specific therapy and may even deteriorate with it. It is important to identify such patients as soon as possible, because they should be treated cautiously and considered for lung transplantation if eligible. High-resolution computed tomography of the chest can suggest PVOD in the setting of pulmonary hypertension when it shows nodular ground-glass opacities, septal lines, lymph node enlargement, and pleural effusion. Similarly, occult alveolar hemorrhage found on bronchoalveolar lavage in patients with pulmonary hypertension is associated with PVOD. We conducted the current study to identify additional clinical, functional, and hemodynamic characteristics of PVOD. We retrospectively reviewed 48 cases of severe pulmonary hypertension: 24 patients with histologic evidence of PVOD and 24 randomly selected patients with idiopathic, familial, or anorexigen-associated PAH and no evidence of PVOD after meticulous lung pathologic evaluation. We compared clinical and radiologic findings, pulmonary function, and hemodynamics at presentation, as well as outcomes after the initiation of PAH therapy in both groups. Compared to PAH, PVOD was characterized by a higher male:female ratio and higher tobacco exposure (p < 0.01). Clinical presentation was similar except for a lower body mass index (p < 0.02) in patients with PVOD. At baseline, PVOD patients had significantly lower partial pressure of arterial oxygen (PaO2), diffusing lung capacity of carbon monoxide/alveolar volume (DLCO/VA), and oxygen saturation nadir during the 6-minute walk test (all p < 0.01). Hemodynamic parameters showed a lower mean systemic arterial pressure (p < 0.01) and right atrial pressure (p < 0.05), but no difference in pulmonary capillary wedge pressure. Four bone morphogenetic protein receptor II (BMPR2) mutations have been previously described in PVOD patients; in the current study we describe 2 additional cases of BMPR2 mutation in PVOD. Computed tomography of the chest revealed nodular and ground-glass opacities, septal lines, and lymph node enlargement more frequently in patients with PVOD compared with patients with PAH (all p < 0.05). Among the 16 PVOD patients who received PAH-specific therapy, 7 (43.8%) developed pulmonary edema (mostly with continuous intravenous epoprostenol, but also with oral bosentan and oral calcium channel blockers) at a median of 9 days after treatment initiation. Acute vasodilator testing with nitric oxide and clinical, functional, or hemodynamic characteristics were not predictive of the subsequent occurrence of pulmonary edema on treatment. Clinical outcomes of PVOD patients were worse than those of PAH patients.

High-dose acetylcysteine in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis is a chronic progressive disorder with a poor prognosis. METHODS: We conducted a double-blind, randomized, placebo-controlled multicenter study that assessed the effectiveness over one year of a high oral dose of acetylcysteine (600 mg three times daily) added to standard therapy with prednisone plus azathioprine. The primary end points were changes between baseline and month 12 in vital capacity and in single-breath carbon monoxide diffusing capacity (DL(CO)). RESULTS: A total of 182 patients were randomly assigned to treatment (92 to acetylcysteine and 90 to placebo). Of these patients, 155 (80 assigned to acetylcysteine and 75 to placebo) had usual interstitial pneumonia, as confirmed by high-resolution computed tomography and histologic findings reviewed by expert committees, and did not withdraw consent before the start of treatment. Fifty-seven of the 80 patients taking acetylcysteine (71 percent) and 51 of the 75 patients taking placebo (68 percent) completed one year of treatment. Acetylcysteine slowed the deterioration of vital capacity and DL(CO): at 12 months, the absolute differences in the change from baseline between patients taking acetylcysteine and those taking placebo were 0.18 liter (95 percent confidence interval, 0.03 to 0.32), or a relative difference of 9 percent, for vital capacity (P=0.02), and 0.75 mmol per minute per kilopascal (95 percent confidence interval, 0.27 to 1.23), or 24 percent, for DL(CO) (P=0.003). Mortality during the study was 9 percent among patients taking acetylcysteine and 11 percent among those taking placebo (P=0.69). There were no significant differences in the type or severity of adverse events between patients taking acetylcysteine and those taking placebo, except for a significantly lower rate of myelotoxic effects in the group taking acetylcysteine (P=0.03). CONCLUSIONS: Therapy with acetylcysteine at a dose of 600 mg three times daily, added to prednisone and azathioprine, preserves vital capacity and DL(CO) in patients with idiopathic pulmonary fibrosis better than does standard therapy alone.

Fibrous remodeling of the pulmonary venous system in pulmonary arterial hypertension associated with connective tissue diseases.

Pulmonary arterial hypertension is a severe complication of connective tissue diseases. It is currently well established that pulmonary arterial hypertension associated with connective tissue diseases such as systemic sclerosis is frequently less responsive or even refractory to pulmonary vasodilator therapies. In that setting, pulmonary venoocclusive disease is believed to contribute to treatment failures. We therefore hypothesized that pulmonary arterial hypertension associated with connective tissue diseases may be associated with obstructive lesions of pulmonary veins. Lung samples from 8 patients with pulmonary arterial hypertension associated with connective tissue disease (4 limited systemic sclerosis, 2 systemic lupus erythematosus, 1 mixed connective tissue diseases, and 1 rheumatoid arthritis) were studied by light microscopy and analyzed by immunohistochemistry (5 postmortem samples, 3 explants after lung transplantation). Findings were compared with 29 pulmonary arterial hypertension cases from patients displaying neither connective tissue diseases nor associated conditions. We found that (a) 6 (75%) of 8 patients with pulmonary arterial hypertension associated with connective tissue diseases showed significant obstructive pulmonary vascular lesions predominating in veins/preseptal venules, as compared with 5 (17.2%) of 29 non-connective tissue diseases control pulmonary arterial hypertension; (b) lesions of small muscular arteries were consistently present in pulmonary arterial hypertension associated with connective tissue diseases, showing mostly intimal fibrosis and thrombotic lesions; and (c) 6 of 8 lung samples from patients with pulmonary arterial hypertension associated with connective tissue diseases revealed perivascular inflammatory infiltration. In conclusion, our study highlights the fact that pulmonary arterial hypertension complicating the course of connective tissue diseases may be characterized by a more frequent involvement of pulmonary veins and may thus explain why these patients are less prone to respond to specific pulmonary arterial hypertension treatment as compared with idiopathic pulmonary arterial hypertension.

Pulmonary vascular lesions in end-stage idiopathic pulmonary fibrosis: Histopathologic study on lung explant specimens and correlations with pulmonary hemodynamics.

In patients presenting with idiopathic pulmonary fibrosis (IPF), modifications of pulmonary vessels are well defined in fibrotic areas but have not been accurately assessed in the intervening patches of preserved lung. Moreover, the relation between pulmonary vessel lesions and pulmonary hemodynamics is not well known. We therefore designed a retrospective study on lung explant specimens from 26 patients with a firm diagnosis of IPF who had undergone lung transplantation. Our aim was to (1) describe the vascular lesions, especially in preserved lung areas, and (2) correlate them with pulmonary hemodynamics. In dense fibrotic zones, thickening of the arterial and venous wall with severe luminal narrowing was present in each patient. In architecturally preserved lung zones, occlusion of venules and small pulmonary veins was observed in 65% of the patients, although there were only mild changes of muscular pulmonary arteries. We found a significant positive correlation between the macroscopic extent of lung fibrosis and mean pulmonary artery pressure, but we failed to find a relation between mean pulmonary artery pressure and venous/venular lesions in nonfibrotic areas. Our study points out that in many patients with IPF, nonfibrotic lung areas demonstrate an occlusive venopathy, the signification of which remains undetermined.

Pulmonary hyalinizing granuloma: a multicenter study of 5 new cases and review of the 135 cases of the literature.

Pulmonary hyalinizing granuloma (PHG) is a rare disease characterized by single or multiple benign lung nodules mimicking lung neoplasma. Histologic analysis reveals homogenous hyaline lamellae, usually surrounded by collection of plasma cells, lymphocytes and histiocytes in a perivascular distribution. The clinical and radiological findings have been described in small series, but the long-term outcomes have rarely been reported. The objectives were to describe the clinical, radiological and outcomes of PHG in new cases and through a literature review. Patients with PHG were found by a multicenter search among French departments of internal medicine, pulmonology and anatomo-pathology. Review of the literature was made through the National Library of Medicine's MEDLINE database using keywords "hyalinizing granuloma." Five news cases and 135 cases of the literature were found. There were 82 men and 57 women, mean age at the diagnosis 44.6 years (15-83). Patients were frequently asymptomatic (n = 39, 27.4 %). The nodule was unique in 37 cases (28.9 %) and multiple in 91 cases (71.1 %). 18FDG PET scan revealed hypermetabolism of the nodule in 9/15 cases (60 %). A systemic disease was associated in 65 cases (mainly mediastinal and retroperitoneal fibrosis, autoimmune, tumoral or infectious disease or thromboembolism). The outcomes were evaluated in 73 patients when follow-up was available: 14 patients had a surgical resection of the nodule. Forty-five patients did not receive any immunosuppressive drug. Among these patients, 2 improved, 29 were stable and 14 worsened. Corticosteroids were used as a monotherapy in 19 patients and led to radiological improvement in 8 cases, stabilization in 8 cases and worsening in 3 cases. Five patients were treated with corticosteroids and at least one immunosuppressive drug and 4 patients improved. PHG is a rare benign disease, mimicking lung neoplasma, frequently associated with systemic diseases.

Long-term controlled immortalization of a primate hepatic progenitor cell line after Simian virus 40 T-Antigen gene transfer.

Hepatoblasts are bipotent progenitors of both hepatocytes and cholangiocytes. The lack of stable in vitro culture systems for such cells makes it necessary to generate liver progenitor cell lines by means of immortalization. In this study, we describe the long-term behaviour of a clone of simian foetal hepatic progenitor cells immortalized by Simian virus 40 (SV40) large T-antigen (T-Ag) flanked by loxP sites. Immortalization was associated with the re-expression of telomerase activity, which decreased at late passages (population doubling 120) after more than a year in culture. This decrease was concomitant to telomere shortening and karyotypic instability. However, the chromosomes carrying the p53 gene remained intact and long-term immortalized progenitor cells maintained contact inhibition and proliferative properties. They also displayed the features of a normal bipotent phenotype. We constructed a retroviral vector expressing an inducible Cre recombinase and transferred it into the immortalized progenitors. Activation of the Cre recombinase by 4-hydroxy-tamoxifen induced SV40 T-Ag excision, leading to the death of cells expressing Cre recombinase. Immortalized progenitors at late passages stopped growing and eventually disappeared after transplantation into the livers of immunocompromised mice. These cells provide a novel model to study hepatic differentiation and carcinogenesis.

Ocular adnexal marginal zone B cell lymphoma: a clinical and pathologic study of 23 cases.

To better characterize ocular adnexal marginal zone lymphoma of mucosa-associated lymphoid tissue (MZL-MALT), we analyzed the clinical and pathologic features of 23 patients (11 men, 12 women, median age 66 years). The tumor was confined to one ocular structure in 18 cases (conjunctiva, n=8; orbit, n=8; or lacrimal gland, n=2). Concurrent extraorbital disease was detected by the staging procedure in five patients, and preferentially involved other MALT sites. Histogenetic B cell marker studies, available in 13 cases, showed an early post-germinal center (GC) phenotype (BCL-6(-)/IRF4(+)/CD138(-)) (n=5) or a late post-GC phenotype (BCL-6(-)/IRF4(+)/CD138(+)) (n=8), which could be helpful for discrimination from other types of small-B cell lymphoma. BCL10 was positive in 12 of 13 patients tested, with nuclear (n=4) or cytoplasmic (n=8) immunoreactivity. These staining patterns ruled out t(1;14)(p22;q32) translocation. T(11;18)(q21;q21), another MZL-MALT-specific translocation, was detected by reverse transcriptase polymerase chain reaction in four of 15 patients tested. Clinical outcome was excellent but the overall relapse rate was 26.1% with a median follow-up of 39 months (range 6-132 months). Regardless of the disease stage at diagnosis, combined chemotherapy and radiotherapy seemed to be more effective than chemotherapy alone in ocular adnexal MZL-MALT, as persistent complete remission was achieved in nine patients receiving combination therapy, while six of 14 patients treated with chemotherapy alone relapsed.