Preservation of Organs to Be Transplanted: An Essential Step in the Transplant Process.

Organ transplantation remains the treatment of last resort in case of failure of a vital organ (lung, liver, heart, intestine) or non-vital organ (essentially the kidney and pancreas) for which supplementary treatments exist. It remains the best alternative both in terms of quality-of-life and life expectancy for patients and of public health expenditure. Unfortunately, organ shortage remains a widespread issue, as on average only about 25% of patients waiting for an organ are transplanted each year. This situation has led to the consideration of recent donor populations (deceased by brain death with extended criteria or deceased after circulatory arrest). These organs are sensitive to the conditions of conservation during the ischemia phase, which have an impact on the graft's short- and long-term fate. This evolution necessitates a more adapted management of organ donation and the optimization of preservation conditions. In this general review, the different aspects of preservation will be considered. Initially done by hypothermia with the help of specific solutions, preservation is evolving with oxygenated perfusion, in hypothermia or normothermia, aiming at maintaining tissue metabolism. Preservation time is also becoming a unique evaluation window to predict organ quality, allowing repair and/or optimization of recipient choice.

Transplantation for pulmonary arterial hypertension with congenital heart disease: Impact on outcomes of the current therapeutic approach including a high-priority allocation program.

Patients with end-stage pulmonary arterial hypertension due to congenital heart disease have limited access to heart-lung transplantation or double-lung transplantation. We aimed to assess the effects of a high-priority allocation program established in France in 2007. We conducted a retrospective study to compare waitlist and posttransplantation outcomes before versus after implementation of the high-priority allocation program. We included 67 consecutive patients (mean age at listing, 33.2 ± 10.5 years) with pulmonary arterial hypertension due to congenital heart disease listed for heart-lung transplantation or double-lung transplantation from 1997 to 2016. At one month, the incidences of transplantation and death before transplantation were 3.5% and 24.6% in 1997-2006, 4.8% and 4.9% for patients on the regular list in 2007-2016, and 41.2% and 7.4% for patients listed under the high-priority allocation program (p < .001 and p = .0001, respectively). Overall survival was higher in patients listed in 2007-2016 (84.2% and 61.2% at 1 and 10 years vs. 36.8% and 22.1%, p = .0001). Increased incidence of transplantation, decreased waiting list mortality, and improved early and long-term outcomes were observed in patients with pulmonary arterial hypertension due to congenital heart disease listed for transplantation in the recent era, characterized by implementation of a high-priority allocation program.

Surgical Resection of Tumors Invading the Inferior Vena Cava at the Hepatic Vein and Thoracic Levels.

BACKGROUND: Our aim was to describe the results of our program of surgical resection of tumors invading the inferior vena cava (IVC) at the hepatic and thoracic levels. We hypothesized that similar surgical outcomes may be obtained compared to tumor resection below the hepatic vein level if the liver function was preserved. METHODS: We performed a single-center retrospective study of 72 consecutive patients who underwent surgical resection from 1996 to 2019 for tumors invading the IVC. We compared two groups based on tumor location below (group I/II) or above (group III/IV) the inferior limit of hepatic veins. RESULTS: Tumor histology was similarly distributed between groups. In group III/IV (n = 35), sterno-laparotomy was used in 83% of patients, cardiopulmonary bypass in 77%, and deep hypothermic circulatory arrest in 17%; 23% underwent liver resection. Corresponding proportions in group I/II were 3%, 0%, 0%, and 8%. In group III/IV, 4 patients required emergency resection. Mortality on day 30 was 17% (n = 6) in group III/IV and 0% in group I/II (P = 0.01). There was no liver failure among the 66 postoperative survivors and 5 out of 6 patients who died postoperatively presented a preoperative or postoperative liver failure (P < 0.001). Overall survival was not significantly different between groups with a median follow-up of 15.1 months. R0 resection was achieved in 66% of group I/II and 49% of group III/IV patients (P = 0.03). CONCLUSION: Surgical resection of tumors invading the inferior vena cava at hepatic vein and thoracic levels should be reserved to carefully selected patients without preoperative liver failure to minimize postoperative mortality.

Diffusion-weighted Imaging Voxelwise-matched Analyses of Lung Cancer at 3.0-T PET/MRI: Reverse Phase Encoding Approach for Echo-planar Imaging Distortion Correction.

Background PET/MRI has drawn increasing interest in thoracic oncology due to the simultaneous acquisition of PET and MRI data. Geometric distortions related to diffusion-weighted imaging (DWI) limit the evaluation of voxelwise multimodal analyses. Purpose To assess the effectiveness of reverse phase encoding in correcting DWI geometric distortion for multimodal PET/MRI voxelwise lung tumor analyses. Materials and Methods In this prospective study, reverse phase encoding method was implemented with 3.0-T PET/MRI to correct geometric distortions related to DWI. The method was validated in dedicated phantom and then applied to 12 consecutive patients (mean age, 66 years ± 13 [standard deviation]; 10 men) suspected of having lung cancer who underwent fluorodeoxyglucose PET/MRI between October 2018 and April 2019. The effects on DWI-related image matching and apparent diffusion coefficient (ADC) regional map computation were assessed. Consequences on multimodal PET/MRI voxelwise lung tumor analyses were evaluated. Spearman correlation coefficients (rs) between the standardized uptake value (SUV) and ADC data corrected for distortion were computed from optimal realigned DWI PET data, along with bootstrap confidence intervals. Results Phantom results showed that in highly distorted areas, correcting the distortion significantly reduced the mean error against the ground truth (-25% ± 10.6 to -18.4% ± 12.6; P < .001) and the number of voxels with more than 20% error (from 85.3% to 31.4%). In the 12 patients, the coregistration of multimodal PET/MRI tumor data was improved by using the reverse phase encoding method (0.4%-44%). In all tumors, voxelwise correlations (rs) between ADC and SUV revealed null or weak monotonic relationships (mean rs of 0.016 ± 0.24 with none above 0.5). Conclusion Reverse phase encoding is a simple-to-implement method for improved diffusion-weighted multimodal PET/MRI voxelwise-matched analyses in lung cancer. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Colletti in this issue.

Secondary Extra-anatomic Infrainguinal Bypass following Lower Limb Tumoral Resection.

BACKGROUND: Soft tissue malignancy of lower limb can involve femoral triangle by direct tumoral invasion or secondary to ganglionic metastasis. Secondary arterial complications can appear during follow-up after initial tumoral resection and local radiation therapy. The aim of this study is to report our experience of secondary extra-anatomical lower limb revascularization following lower limb oncological resection with femoral bifurcation involvement. METHODS: This is a retrospective monocentric study including patients who underwent extra-anatomical iliopopliteal bypass, with a previous treated neoplasia involving homolateral femoral bifurcation. Proximal anastomosis was performed on the iliac artery, tunnelization was made through iliac wing, and distal anastomosis was done on distal superficial femoral or popliteal artery. RESULTS: Five patients underwent extra-anatomic iliopopliteal bypass for oncological purpose from 2008 to 2018 at our institution. Mean age at surgery time was 52 years (standard deviation = 19.3). Prosthetic graft was used in all cases. Primitive tumor involved Scarpa triangle in 3 cases (soft tissue sarcomas) and ganglionic metastasis involved Scarpa triangle in 2 cases (epidermoid carcinoma). Clinical presentation was ischemic in 4 cases and hemorrhagic in 1 case. One patient died during hospitalization. Of the 4 survivors, 3 patients had a patent bypass at the end of follow-up (2 had bypass thrombectomy, 1 patient had major amputation). CONCLUSIONS: Secondary iliopopliteal bypasses through the iliac wing following lower limb tumoral resection have acceptable results. It is a valid option for limb salvage especially after local radiation therapy and tumoral resection. Multidisciplinary management is necessary to obtain acceptable results and follow-up is mandatory.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation.

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24hi CD38hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24hi CD38hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9+ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24hi CD38hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

French experience of balloon pulmonary angioplasty for chronic thromboembolic pulmonary hypertension.

AIMS: To evaluate safety and efficacy of balloon pulmonary angioplasty (BPA) in a large cohort of patients with chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: From 2014 to 2017, 184 inoperable CTEPH patients underwent 1006 BPA sessions. Safety and efficacy during the first 21 months (initial period) were compared with those of the last 21 months (recent period). A total of 154 patients had a full evaluation after a median duration of 6.1 months. RESULTS: Overall, there was a significant improvement in New York Heart Association functional class, 6-min walk distance (mean change +45 m), and a significant decrease in mean pulmonary artery pressure (PAP) and in pulmonary vascular resistance (PVR) by 26% and 43%, respectively. The percentage decreases of mean PAP and PVR were 22% and 37% in the initial period versus 30% and 49% in the recent period, respectively (p<0.05). The main complications included lung injury, which occurred in 9.1% of 1006 sessions (13.3% in the initial period versus 5.9% in the recent period; p<0.001). Per-patient multivariate analysis revealed that baseline mean PAP and the period during which BPA procedure was performed (recent versus initial period) were the strongest factors related to the occurrence of lung injury. 3-year survival was 95.1%. CONCLUSION: This study confirms that a refined BPA strategy improves short-term symptoms, exercise capacity and haemodynamics in inoperable CTEPH patients with an acceptable risk-benefit ratio. Safety and efficacy improve over time, underscoring the unavoidable learning curve for this procedure.

Tracheal replacement.

Tracheal reconstruction is one of the greatest challenges in thoracic surgery when direct end-to-end anastomosis is impossible or after this procedure has failed. The main indications for tracheal reconstruction include malignant tumours (squamous cell carcinoma, adenoid cystic carcinoma), tracheoesophageal fistula, trauma, unsuccessful surgical results for benign diseases and congenital stenosis. Tracheal substitutes can be classified into five types: 1) synthetic prosthesis; 2) allografts; 3) tracheal transplantation; 4) tissue engineering; and 5) autologous tissue composite. The ideal tracheal substitute is still unclear, but some techniques have shown promising clinical results. This article reviews the advantages and limitations of each technique used over the past few decades in clinical practice. The main limitation seems to be the capacity for tracheal tissue regeneration. The physiopathology behind this has yet to be fully understood. Research on stem cells sparked much interest and was thought to be a revolutionary technique; however, the poor long-term results of this approach highlight that there is a long way to go in this research field. Currently, an autologous tissue composite, with or without a tracheal allograft, is the only long-term working solution for every aetiology, despite its technical complexity and setbacks.

Exploring antibody-dependent adaptive immunity against aortic extracellular matrix components in experimental aortic aneurysms.

BACKGROUND: Recent evidence suggests that adaptive immunity develops during abdominal aortic aneurysm evolution. Uncertainties remain about the antigens implicated and their role in inducing rupture. Because antigens from the extracellular matrix (ECM) have been suspected, the aim of this experimental study was to characterize the role of adaptive immunity directed against antigens from the aortic ECM. METHODS: In a first step, an experimental model of abdominal aortic aneurysm rupture based on adaptive immunity against the ECM was developed and characterized. Forty 4-week-old male Lewis rats were divided into two groups. In the ECM group (n = 20), rats were presensitized against the guinea pig aortic ECM before implantation of a decellularized aortic xenograft (DAX). In the control group (n = 20), rats were not presensitized before DAX implantation. In each group, half the rats were sacrificed at day 3 to analyze early mechanisms involved after DAX implantation. In a second step, we aimed to assess which ECM component was most efficient in inducing rupture. For this purpose, the nonfibrillar and fibrillar ECM components were sequentially extracted from the guinea pig aortic wall. Forty Lewis rats were then divided into four groups. Each group was presensitized against one ECM component (structural glycoproteins and proteoglycans, collagen, elastin alone, and elastin-associated glycoproteins) before DAX implantation. Apart from those that experienced rupture, rats were sacrificed at day 21. Xenografts were harvested for histologic, immunofluorescence, and conditioned medium analyses. RESULTS: In total, early aortic rupture occurred in 80% of the ECM group vs 0% of the control group (P < .001). In the ECM group, major circumferential immunoglobulin deposits were observed in combination with the C3 complement fraction, without cell infiltration. Conditioned medium analysis revealed that matrix metalloproteinase 9 and myeloperoxidase levels and elastase activities were significantly increased in this group. Immunofluorescence analysis demonstrated that myeloperoxidase co-localized with tissue-free DNA and histone H4, highlighting local neutrophil activation and formation of neutrophil extracellular traps. Following differential presensitization, it appeared that rats presensitized against structural glycoproteins and proteoglycans were significantly more susceptible to rupture after DAX implantation. CONCLUSIONS: Stimulating adaptive immunity against the aortic ECM, especially structural glycoproteins and proteoglycans, triggers rupture after DAX implantation. Further studies are needed to assess the precise proteins involved.

Should surgery be part of the multimodality treatment for stage IIIB non-small cell lung cancer?

BACKGROUND: Traditionally, treatment for stage IIIB (T4N2M0 and T1-4N3M0) NSCLC consists in definitive chemoradiation. Surgery is used only anecdotally. Here, we studied outcome for patients treated with multimodality including surgery. METHODS: Patients who underwent surgery for stage IIIB between 2000 and 2015 were retrospectively reviewed and data analyzed. Patients were selected for surgery if they would tolerate multimodality treatment, the tumor was deemed upfront resectable, and N2-N3 involvement was limited to a non-bulky single site. Survival was calculated from the date of surgery until last follow-up. Univariate and multivariate analysis were performed to identify prognostic factors. RESULTS: During the study period, 5416 patients underwent resection for NSCLC in our center. Sixty patients (1%) had clinical stage IIIB. Thirty-two patients had T4N2 NSCLC involving the carina and/or superior vena cava (n = 25, 78%), left atrium (n = 5, 16%), or other (n = 2, 6%). Half of the 28 patients with N3-disease had supraclavicular node involvement. Pneumonectomy was performed in 27 patients (45%). Twenty-nine patients (48%) had induction therapy, with chemotherapy alone. Adjuvant therapy was administered to 52 patients (87%), mostly chemoradiation. Complete resection rate was 92%. Post-operative mortality was 3%. Three- and 5-year overall survivals were 51% and 39%, respectively. Multivariate analysis identified incomplete resection (P = 0.008) and absence of adjuvant treatment (P = 0.032) as poor survival prognostic factors. CONCLUSIONS: Surgery can be considered as a component of multimodality therapy in highly selected patients with stage IIIB NSCLC based on encouraging 5-year survival of 39%.

Chronic effects of air pollution on lung function after lung transplantation in the Systems prediction of Chronic Lung Allograft Dysfunction (SysCLAD) study.

An irreversible loss in lung function limits the long-term success in lung transplantation. We evaluated the role of chronic exposure to ambient air pollution on lung function levels in lung transplant recipients (LTRs).The lung function of 520 LTRs from the Cohort in Lung Transplantation (COLT) study was measured every 6 months. The levels of air pollutants (nitrogen dioxide (NO2), particulate matter with an aerodynamic cut-off diameter of x µm (PMx) and ozone (O3)) at the patients' home address were averaged in the 12 months before each spirometry test. The effects of air pollutants on forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) in % predicted were estimated using mixed linear regressions. We assessed the effect modification of macrolide antibiotics in this relationship.Increased 12-month levels of pollutants were associated with lower levels of FVC % pred (-2.56%, 95% CI -3.86--1.25 for 5 µg·m-3 of PM10; -0.75%, 95% CI -1.38--0.12 for 2 µg·m-3 of PM2.5 and -2.58%, 95% CI -4.63--0.53 for 10 µg·m-3 of NO2). In patients not taking macrolides, the deleterious association between PM and FVC tended to be stronger and PM10 was associated with lower FEV1Our study suggests a deleterious effect of chronic exposure to air pollutants on lung function levels in LTRs, which might be modified with macrolides.

Poor predictive value of positive interim FDG-PET/CT in primary mediastinal large B-cell lymphoma.

PURPOSE: Though commonly used to assess response to therapy, the prognostic value of interim FDG-PET/CT in Primary Mediastinal Large B-cell Lymphoma (PMBCL) is unclear. METHODS: We conducted a retrospective study on 36 consecutive patients treated at our institution for a PMBCL between 2006 and 2014. All patients with a positive interim FDG-PET/CT had undergone histological restaging consisting either in a surgical debulking of the residual lesion (15 patients) or a CT-guided core needle biopsy (two patients). All FDG-PET/CT were secondarily reviewed according to the more recent Deauville criteria. RESULTS: Interim FDG-PET/CT was considered positive in 17/36 patients using visual evaluation. Among these patients, 14 had a Deauville score of 4. Histological restaging was negative in all but one case, showing inflammation and/or fibrosis. After a median follow-up of 48.5 months, a total of five patients have relapsed, two patients in the positive FDG-PET/CT group, and three patients in the negative FDG-PET/CT group, respectively. CONCLUSIONS: These data indicate that a positive interim FDG-PET/CT does not reflect persistence of active disease in the vast majority of PMBCL cases. The relapse rate appears similar regardless of interim FDG-PET/CT results and interpretation criteria. This suggests that interim FDG-PET/CT has a poor positive predictive value, thus kt should be used with caution in PMBCL.

Extracorporeal life support in lung and heart-lung transplantation for pulmonary hypertension in adults.

After bilateral lung and heart-lung transplantation in adults with pulmonary hypertension, hemodynamic and oxygenation deficiencies are life-threatening complications that are increasingly managed with extracorporeal life support (ECLS). The primary aim of this retrospective study was to assess 30-day and 1-year survival rates in patients managed with vs without post-operative venoarterial ECLS in 2008-2013. The secondary endpoints were the occurrence rates of nosocomial infection, bleeding, and acute renal failure. Of the 93 patients with pulmonary hypertension who received heart-lung (n=29) or bilateral lung (n=64) transplants, 28 (30%) required ECLS a median of 0 [0-6] hours after surgery completion and for a median of 3.0 [2.0-8.5] days. Compared to ECLS patients, controls had higher survival at 30 days (95.0% vs 78.5%; P=.02) and 1 year (83% vs 64%; P=.005), fewer nosocomial infections (48% vs 79%; P=.0006), and fewer bleeding events (17% vs 43%; P=.008). The need for renal replacement therapy was not different between groups (11% vs 17%; P=.54). Venoarterial ECLS is effective in treating pulmonary graft dysfunction with hemodynamic failure after heart-lung or bilateral lung. However, ECLS use was associated with higher rates of infection and bleeding.

Type II endoleak prevention with coil embolization during endovascular aneurysm repair in high-risk patients.

OBJECTIVE: This study evaluated endoleak level and size decrease of infrarenal abdominal aortic aneurysm (AAA) after endovascular aneurysm repair (EVAR) with coil embolization in patients at high risk for type II endoleak. METHODS: Between 2009 and 2013, 83 of 187 patients (44.3%) who underwent EVAR for AAA also underwent coil embolization of the aneurysm sac immediately after complete stent graft release because of risk factors for type II endoleak, including absence of a circumferential thrombus, two or more pairs of patent lumbar arteries, or a patent inferior mesenteric artery. Coil embolization was achieved using a 4F catheter with a microcatheter placed between the stent graft and the aneurysm wall. Computed tomography and color duplex ultrasound imaging were performed 1, 6, 12, and 24 months later to look for an endoleak and assess aneurysm sac diameter. RESULTS: Mean follow-up was 24 ± 11 months (range, 6-53 months). A mean of 12 coils (range, 4-23) was used. Technical success was achieved in all patients, with no procedurally related complications. Follow-up computed tomography showed type II endoleak in one patient. Aneurysm sac diameter was significantly decreased after 6 months (P = .001), 12 months (P = .001), and 24 months (P = .001). Surgery was required in one patient for common femoral artery occlusion unrelated to the procedure and in another patient for distal type I endoleak. CONCLUSIONS: Aneurysm sac coil embolization during EVAR for patients at risk for type II endoleak is technically feasible, safe, and effective in preventing type II endoleak. This procedure leads to rapid AAA shrinkage. Thus, coil embolization could be used routinely to improve EVAR outcomes for patients at risk for type II endoleak.

Lymphoproliferative Disorders after Lung Transplantation: Clinicopathological Characterization of 16 Cases with Identification of Very-Late-Onset Forms.

BACKGROUND: The incidence of posttransplant lymphoproliferative disorders (PTLD) has recently declined, but late cases are increasingly reported in lung transplant recipients. OBJECTIVES: We present our experience with PTLD after lung transplantation, attempting to examine the distinguishing characteristics of early versus late cases. METHODS: We have reviewed clinical and pathological data of all cases occurring in our institution between 2001 and 2014. RESULTS: Patients, aged 15-63 years, were mostly (12/16) Epstein-Barr virus (EBV) seropositive at the time of transplantation. Eleven early cases, occurring 9.4 ± 5.2 months after transplantation and mostly (9/11) prior to 2010, had EBV+ diffuse large B-cell lymphomas. Lungs and/or thoracic lymph nodes were often involved (n = 8). Treatments included reduction of immune suppression (n = 11), rituximab (n = 8) and chemotherapy (n = 7). Two patients are in complete remission at 26 and 216 months. Nine patients died 8.0 ± 6.5 months after PTLD diagnosis. Of the 5 cases with late PTLD occurring 4-23 years (mean ± SD: 10.4 ± 7.7) after transplantation (and 3/5 after 2009), 1 had pulmonary lymphomatoid granulomatosis (only endothoracic case), 1 cutaneous large T-cell lymphoma, 2 had anaplastic large cell lymphomas, and 1 Hodgkin's disease. Two of the 5 cases were EBV-, including one followed by a second EBV+ PTLD after 8 years of complete remission. Two patients were alive and well (follow-up: 44 and 151 months), one having suffered from EBV-related cholestatic hepatitis 6 years after the PTLD. CONCLUSION: Our small experience shows a trend toward (very) late occurrence, associated with more unusual clinicopathologic features, but not with a worse prognosis.

Thoracic endometriosis: clinicopathologic updates and issues about 18 cases from a tertiary referring center.

Thoracic endometriosis is defined as the ectopic presence of endometrial glands and stroma in lung or pleura and constitutes an uncommon cause of spontaneous pneumothorax in nonsmoker women in childbearing age. From 2000 to 2014, 18 (7.3%) women of 246 had a histologically proven endometriosis-related pneumothorax. The examination of thoracic samples was performed on formalin-fixed, paraffin-embedded hematoxylin and eosin-stained slides. Immunohistochemistry was carried out on all samples. The pathologic findings included endometriosis foci appearing as a triad of endometrial glands, stroma, and hemosiderin-laden macrophages in 8 patients. In the remaining 10 patients, minute nests of endometrial stroma were recognized at histologic examination and immunohistochemistry. One patient displayed diaphragmatic endometriosis and pulmonary lymphangioleiomyomatosis. Thoracic endometriosis is an uncommon cause of recurrent pneumothorax necessitating histologic confirmation. The histologic diagnosis of endometriosis may be challenging on small pleural or lung biopsies because endometriosis mostly appears as minute nests of endometrial stromal cells. Here, we present our experience on thoracic endometriosis: considering frequent interpretation difficulties of biopsy samples, we propose a multidisciplinary diagnostic algorithm.

Angiomatoid fibrous histiocytoma of the pulmonary artery: a multidisciplinary discussion.

AIMS: Angiomatoid fibrous histiocytoma (AFH) is a rare neoplastic disease usually occurring in the dermis or subcutis of the extremities of young adults or children. Although sporadic cases in deep soft tissue and visceral organs have been reported, we present here the first description of AFH developing in a large artery. METHODS AND RESULTS: Paraffin sections of the surgical specimen were stained with haematoxylin and eosin, and immunohistochemistry was performed (CKAE1/AE3, EMA, CD34, p63, CD38, smooth muscle actin, and desmin). In addition, FISH and RT-PCR were applied in order to check for EWRS rearrangement. The histomorphological features, and FISH analysis revealing rearrangement of EWSR, indicated the definitive diagnosis of AFH. RT-PCR confirmed EWSR rearrangement, and detected an EWSR1-ATF1 fusion transcript. CONCLUSIONS: A thoracic location of AFH has not been reported until very recently, and shares a differential diagnosis with diverse neoplasms, including spindle cell carcinoma and low-grade sarcoma. We describe the first reported case of thoracic AFH arising in a large vessel, and highlight distinctive histological and molecular features.

Pulmonary lymphoid neogenesis in idiopathic pulmonary arterial hypertension.

RATIONALE: Patients with idiopathic pulmonary arterial hypertension (IPAH) present circulating autoantibodies against vascular wall components. Pathogenic antibodies may be generated in tertiary (ectopic) lymphoid tissues (tLTs). OBJECTIVES: To assess the frequency of tLTs in IPAH lungs, as compared with control subjects and flow-induced PAH in patients with Eisenmenger syndrome, and to identify local mechanisms responsible for their formation, perpetuation, and function. METHODS: tLT composition and structure were studied by multiple immunostainings. Cytokine/chemokine and growth factor expression was quantified by real-time polymerase chain reaction and localized by immunofluorescence. The systemic mark of pulmonary lymphoid neogenesis was investigated by flow cytometry analyses of circulating lymphocytes. MEASUREMENTS AND MAIN RESULTS: As opposed to lungs from control subjects and patients with Eisenmenger syndrome, IPAH lungs contained perivascular tLTs, comprising B- and T-cell areas with high endothelial venules and dendritic cells. Lymphocyte survival factors, such as IL-7 and platelet-derived growth factor-A, were expressed in tLTs as well as the lymphorganogenic cytokines/chemokines, lymphotoxin-α/-ß, CCL19, CCL20, CCL21, and CXCL13, which might explain the depletion of circulating CCR6(+) and CXCR5(+) lymphocytes. tLTs were connected with remodeled vessels via an ER-TR7(+) stromal network and supplied by lymphatic channels. The presence of germinal center centroblasts, follicular dendritic cells, activation-induced cytidine deaminase, and IL-21(+)PD1(+) follicular helper T cells in tLTs together with CD138(+) plasma cell accumulation around remodeled vessels in areas of immunoglobulin deposition argued for local immunoglobulin class switching and ongoing production. CONCLUSIONS: We highlight the main features of lymphoid neogenesis specifically in the lungs of patients with IPAH, providing new evidence of immunological mechanisms in this severe condition.