Therapeutic Vaccination against Human Papillomavirus Type 16 for the Treatment of High-Grade Anal Intraepithelial Neoplasia in HIV+ Men.

PURPOSE: Anal cancer is increasing in HIV+ men who have sex with men (MSM). Treatment options for its precursor, high-grade anal intraepithelial neoplasia (HGAIN), are suboptimal. In this phase I to II dose-finding study, we assessed the safety and efficacy of the human papillomavirus type 16 (HPV16) synthetic long peptide vaccine (SLP-HPV-01) in HIV+ MSM with HPV16-positive HGAIN. PATIENTS AND METHODS: Four dosage schedules (1-5-10; 5-10-20; 10-20-40; and 40-40-40-40 µg) of SLP-HPV-01 were administered intradermally with a 3-week interval in 10 patients per dose level (DL). In each dose group, 5 patients also received 1 µg/kg pegylated IFNα-2b subcutaneously. Primary endpoints were safety and regression of HGAIN at 3, 6, and 12 months. RESULTS: Eighty-one of 134 screened patients (60%) had HPV16-negative HGAIN lesions, leaving 53 eligible patients. Thirteen patients were excluded, leaving 40 men. The vaccine was well tolerated. One patient developed a generalized rash. The highest dosage level induced the strongest immune responses. There was no indication for stronger reactivity in the IFNα groups. Up to 18 months of follow-up, 8/38 intention-to-treat patients had a complete clinical and histologic response and one had a partial response (in total 9/38, 23.7%). At the highest dosage level, the clinical response was 4/10 (40%). Stronger immune responses were detected among clinical responders. CONCLUSIONS: The highest DL is safe, immunogenic, and associated with clinical responses to HPV16-induced lesions. However, as the majority of HGAIN is caused by the other HPV types, further studies should aim at pan-HPV vaccination to prevent or treat HGAIN.

Lymphatic differentiation and microvascular proliferation in benign vascular lesions of skin and soft tissue: Diagnostic features following the International Society for The Study of Vascular Anomalies Classification-A retrospective study.

Background: Discrepancies have been noted between the clinical and histologic diagnosis of vascular malformations. Objective: To evaluate the effectiveness of the International Society for Study of Vascular Anomalies (ISSVA) classification in diagnosing benign vascular anomalies based on clinical and (immuno) histologic parameters, focusing on lymphatic differentiation and vascular proliferation. Method: A retrospective study of 121 consecutive patients with benign skin and soft-tissue vascular anomalies located in the head and neck region (pyogenic granulomas and angioma senilis were excluded) by applying multiplex immunohistochemistry staining for lymph vessels (D2-40), endothelial blood vessels, and proliferating cells (Ki67). Clinical and histologic diagnosis was revised after the ISSVA classification. Results: Initially, 64 lesions were diagnosed as tumors and 57 as malformations. Revision diagnosis following the ISSVA classification revealed 27 tumors, 90 malformations (22.2% lymphatic), and 4 non-ISSVA. Immunostaining showed lymphatic differentiation in 24 (19.8%) of 121 cases, of which 20 were malformations. Proliferative activity (Ki67+) was found in 41 (33.8%) of 121 cases, of which 8 were arteriovenous malformations. Limitation: Quality and size of materials (biopsies vs resections) and clinical information. Conclusion: The diagnostic accuracy of combined histologic and clinical approaches for identifying vascular anomalies following the ISSVA classification can be substantially enhanced by incorporating additional immunostaining techniques to evaluate lymphatic differentiation and proliferative activity, particularly in identifying the occurrence of vascular malformations.

Microvascular proliferation in arteriovenous malformation of the hand worsens during pregnancy: a case report.

Arteriovenous malformations (AVMs) are rare congenital disorders characterized by episodes of disproportionate growth that can cause pain and severe bleeding, with microvascular proliferation (MVP) associated with these episodes. Hormonal influences can also worsen the symptoms in patients with AVM. Case presentation: This case report presents a female patient with congenital vascular malformations of the left hand since birth, whose symptoms worsened during puberty and pregnancy, ultimately leading to amputation of the left hand due to unbearable pain and loss of function. Pathologic analysis revealed substantial MVP activity within the tissues of the AVM, with an expression of receptors for estrogen, growth hormone, and follicle-stimulating hormone in the vessels of the AVM, including MVP areas. Resected materials not related to pregnancy revealed chronic inflammation and fibrosis but hardly any MVP. Discussion and conclusion: These findings suggest a role for MVP in the progressive growth of AVM during pregnancy, with a potential role for hormonal influences. The case highlights the relationship between AVM symptoms and size during pregnancy and the pathological findings of MVP areas within the AVM with hormone receptor expression on proliferating vessels in resected materials.

Tissues attached to retrieved leadless pacemakers: Histopathological evaluation of tissue composition in relation to implantation time and complications.

BACKGROUND: Leadless pacemakers (LPs) have proven safe and effective, but device revisions remain necessary. Either replacing the LP or implanting a new adjacent LP is feasible. Replacement seems more appealing, but encapsulation and tissue adhesions may hamper the safety and efficacy of LP retrieval. OBJECTIVE: We determined the incidence and cellular characteristics of tissue adherent to retrieved LPs and the potential implications for end-of-life strategy. METHODS: All 15 consecutive successful Nanostim LP retrievals in a tertiary center were included. We assessed the histopathology of adherent tissue and obtained clinical characteristics. RESULTS: Adherent tissue was present in 14 of 15 retrievals (93%; median implantation duration 36 months; range 0-96 months). The tissue consisted of fibrosis (n = 2), fibrosis and thrombus (n = 9), or thrombus only (n = 3). In short-term retrievals (<1 year), mostly fresh thrombi without fibrosis were seen. In later retrievals, the tissue consisted of fibrosis often with organizing or lytic thrombi. Fibrosis showed different stages of organization, notably early fibrocellular and later fibrosclerotic tissue. Inflammatory cells were seen (n = 4) without signs of infection. Tricuspid valve material was retrieved in 1 patient after 36 months, resulting in increased tricuspid regurgitation. CONCLUSION: Our results suggest that fibrosis and thrombus adherent to LPs are common and encapsulate the LP as seen in transvenous pacemakers. LPs may adhere to the tricuspid valve or subvalvular apparatus affecting retrieval safety. The end-of-life strategy should be optimized by incorporating risk stratification for excessive fibrotic encapsulation and adhesions.

Pathological features of COVID-19-associated myocardial injury: a multicentre cardiovascular pathology study.

AIMS: Coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been associated with cardiovascular features of myocardial involvement including elevated serum troponin levels and acute heart failure with reduced ejection fraction. The cardiac pathological changes in these patients with COVID-19 have yet to be well described. METHODS AND RESULTS: In an international multicentre study, cardiac tissue from the autopsies of 21 consecutive COVID-19 patients was assessed by cardiovascular pathologists. The presence of myocarditis, as defined by the presence of multiple foci of inflammation with associated myocyte injury, was determined, and the inflammatory cell composition analysed by immunohistochemistry. Other forms of acute myocyte injury and inflammation were also described, as well as coronary artery, endocardium, and pericardium involvement. Lymphocytic myocarditis was present in 3 (14%) of the cases. In two of these cases, the T lymphocytes were CD4 predominant and in one case the T lymphocytes were CD8 predominant. Increased interstitial macrophage infiltration was present in 18 (86%) of the cases. A mild pericarditis was present in four cases. Acute myocyte injury in the right ventricle, most probably due to strain/overload, was present in four cases. There was a non-significant trend toward higher serum troponin levels in the patients with myocarditis compared with those without myocarditis. Disrupted coronary artery plaques, coronary artery aneurysms, and large pulmonary emboli were not identified. CONCLUSIONS: In SARS-CoV-2 there are increased interstitial macrophages in a majority of the cases and multifocal lymphocytic myocarditis in a small fraction of the cases. Other forms of myocardial injury are also present in these patients. The macrophage infiltration may reflect underlying diseases rather than COVID-19.

Fibrotic aortic valve disease after radiotherapy: an immunohistochemical study in breast cancer and lymphoma patients.

BACKGROUND: Radiation-associated aortic valve (AV) stenosis is frequently seen as a late sequela after thoracic radiotherapy (RT). Although the clinical relationship between thoracic radiotherapy and valvular dysfunction has been established, the process leading to accelerated aortic valve stenosis remains unclear. The aim of this study was to determine whether increased inflammatory cell infiltration, fibrosis, and calcification is present in aortic valves after radiotherapy at the time of aortic valve replacement. METHODS: Stenotic aortic valve specimens from 43 patients were obtained after surgical aortic valve replacement. A total 28 patients had previously undergone radiotherapy for breast cancer or malignant lymphoma. A total 15 patients were included as control. The valve leaflets were assessed by (immuno)histochemistry for inflammatory cell composition (CD3, CD20, CD68, and CD163) and extracellular matrix changes (collagen and calcification). RESULTS: Aortic valve cell density after radiotherapy for lymphoma was markedly decreased when compared with other groups. Irradiated aortic valve show similar (low) degrees of late T and B lymphocyte infiltration as control valves, whereas macrophage marker CD68 was decreased after radiotherapy for breast cancer. Collagen content was increased following radiotherapy. Aortic valves of patients with lymphoma contained significantly less calcified tissue when compared with the other groups. CONCLUSION: High-dose radiation at a young age (patients with lymphoma) results in cell loss and premature fibrotic aortic valve stenosis as opposed to the degenerative calcific stenosis observed in patients with breast cancer. Our findings suggest a possible dose-dependent effect of radiotherapy on aortic valve fibrosis. The active presence of inflammatory cells may be limited to the acute phase after radiotherapy.

Feasibility of mapping and cannulation of the porcine epicardial lymphatic system for sampling and decompression in heart failure research.

BACKGROUND AND AIM: The cardiac lymphatic system drains excess fluid from the cardiac interstitium. Any impairment or dysfunction of the lymph structures can result in the accumulation of interstitial fluid, and may lead to edema and eventually cardiac dysfunction. Lymph originates directly from the interstitium and carries real-time information about the metabolic state of cells in specific regions of the heart. The detailed anatomy of the epicardial lymphatic system in individuals is broadly unknown. Generally, the epicardial lymphatic system is not taken into consideration during heart surgery. This study investigates the feasibility of detailed mapping and cannulation of the porcine epicardial lymphatic system for use in preservation of explanted hearts and heart failure studies in pigs and humans. METHODS: The anatomy of the epicardial lymphatic systems of forty pig hearts was studied and documented. Using a 27 G needle, India ink was introduced directly into the epicardial lymphatic vessels in order to visualise them. Based on the anatomical findings thus obtained, two cannulation regions for the left and right principal trunks were identified. These regions were cannulated with a 26 G intravenous Venflon cannula-over-needle, and a Galeo Hydro Guide F014 wire was used to verify that the lumen was patent. RESULTS: The main epicardial lymphatic collectors were found to follow the main coronary arteries. Most of the lymph vessels drained into the left ventricular trunk, which evacuates fluid from the left heart and also partially from the right heart. The right trunk was often found to drain into the left trunk anterior basally. Right heart drainage was highly variable compared to the left. In addition, the overall cannulation success rate of the selected cannulation sites was only 57%. CONSLUSIONS: Mapping of the porcine epicardial lymphatic anatomy is feasible. The right ventricular drainage system had a higher degree of variability than the left, and the right cardiac lymph system was found to be partially cleared through the left lymphatic trunk. To improve cannulation success rate, we proposed two sites for cannulation based on these findings and the use of Venflon cannulas (26 G) for cannulation and lymph collection. This method might be helpful for future studies that focus on biochemical sample analysis and decompression. RELEVANCE FOR PATIENTS: Real-time biochemical assessment and decompression of lymph may contribute to the understanding of heart failure and eventually result in preventive measures. First its relevance should be established by additional research in both arrested and working porcine hearts. Imaging and mapping of the epicardial lymphatics may enable sampling and drainage and contribute to the prevention or treatment of heart failure. We envision that this approach may be considered in patients with a high risk of postoperative left and right heart failure during open-heart surgery.

Protease-activated receptors are potential regulators in the development of arterial endofibrosis in high-performance athletes.

OBJECTIVE: High-performance athletes can develop symptomatic arterial flow restriction during exercise caused by endofibrosis. The pathogenesis is poorly understood; however, coagulation enzymes, such as tissue factor (TF) and coagulation factor Xa, might contribute to the fibrotic process, which is mainly regulated through activation of protease-activated receptors (PARs). Therefore, the aim of this explorative study was to evaluate the presence of coagulation factors and PARs in endofibrotic tissue, which might be indicative of their potential role in the natural development of endofibrosis. METHODS: External iliac arterial specimens with endofibrosis (n = 19) were collected during surgical interventions. As control, arterial segments of the external iliac artery (n = 20) were collected post mortem from individuals with no medical history of cardiovascular disease who donated their body to medical science. Arteries were paraffinized and cut in tissue sections for immunohistochemical analysis. Positive staining within lesions was determined with ImageJ software (National Institutes of Health, Bethesda, Md). RESULTS: Endofibrotic segments contained a neointima, causing intraluminal stenosis, which was highly positive for collagen (+150%; P < .01) and elastin (+148%; P < .01) in comparison with controls. Intriguingly, endofibrosis was not limited to the intima because collagen (+213%) and elastin (+215%) were also significantly elevated in the media layer of endofibrotic segments. These findings were accompanied by significantly increased α-smooth muscle actin-positive cells, morphologically compatible with the presence of myofibroblasts. In addition, PAR1 and PAR4 and the membrane receptor TF were increased as well as coagulation factor X. CONCLUSIONS: We showed that myofibroblasts and the accompanying collagen and elastin synthesis might be key factors in the development of endofibrosis. The special association with increased presence of PARs, factor X, and TF suggests that protease-mediated cell signaling could be a contributing component in the mechanisms leading to endofibrosis.

Extracellular traps derived from macrophages, mast cells, eosinophils and neutrophils are generated in a time-dependent manner during atherothrombosis.

Extracellular traps generated by neutrophils contribute to thrombus progression in coronary atherosclerotic plaques. It is not known whether other inflammatory cell types in coronary atherosclerotic plaque or thrombus also release extracellular traps. We investigated their formation by macrophages, mast cells, and eosinophils in human coronary atherosclerosis, and in relation to the age of thrombus of myocardial infarction patients. Coronary arteries with thrombosed or intact plaques were retrieved from patients who died from myocardial infarction. In addition, thrombectomy specimens from patients with myocardial infarction were classified histologically as fresh, lytic or organised. Neutrophil and macrophage extracellular traps were identified using sequential triple immunostaining of CD68, myeloperoxidase, and citrullinated histone H3. Eosinophil and mast cell extracellular traps were visualised using double immunostaining for eosinophil major basic protein or tryptase, respectively, and citrullinated histone H3. Single- and double-stained immunopositive cells in the plaque, adjacent adventitia, and thrombus were counted. All types of leucocyte-derived extracellular traps were present in all thrombosed plaques, and in all types of the in vivo-derived thrombi, but only to a much lower extent in intact plaques. Neutrophil traps, followed by macrophage traps, were the most prominent types in the autopsy series of atherothrombotic plaques, including the adventitia adjacent to thrombosed plaques. In contrast, macrophage traps were more numerous than neutrophil traps in intact plaques (lipid cores) and organised thrombi. Mast cell and eosinophil extracellular traps were also present, but sparse in all instances. In conclusion, not only neutrophils but also macrophages, eosinophils, and mast cells are sources of etosis involved in evolving coronary thrombosis. Neutrophil traps dominate numerically in early thrombosis and macrophage traps in late (organising) thrombosis, implying that together they span all the stages of thrombus progression and maturation. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Patched-2 functions to limit Patched-1 deficient skin cancer growth.

PURPOSE: Basal cell carcinoma (BCC) is one of the most common skin cancers, and is typically driven by an aberrantly activated Hedgehog (Hh) pathway. The Hh pathway is regulated by interactions between the Patched-1 (Ptch1) and Smoothened (Smo) receptors. Smo is an activating receptor and is subject to inhibition by Ptch1. Following ligand binding to Ptch1, its inhibitory action is relieved and pathway activation occurs. This receptor interaction is pivotal to restraining uncontrolled cellular growth. Both receptors have been found to be frequently mutated in BCCs. Ptch2 is a Ptch1 paralog that exhibits overlapping functions in both normal development and tissue homeostasis. As yet, its contribution to cancer growth is poorly defined. Here we set out to assess how Ptch2 inhibits BCC growth. METHODS: We used several in vitro readouts for transcriptional and chemotactic Hh signaling in BCC-derived ASZ001 cells, and a novel xenograft model to assess in vivo BCC tumor growth. Gene editing by TALEN was used to untangle the different Ptch2-dependent responses to its ligand sonic hedgehog (Shh). RESULTS: We first defined the signaling competence of Ptch2 in Ptch1-deficient ASZ001 cells in vitro, and found that Ptch2 ligand binding drives their migration rather than eliciting a transcriptional response. We found that subsequent targeting of Ptch2 abrogated the chemotaxic effect. Next, we tested the contribution of Ptch2 to in vivo tumor growth using a xenograft model and found that reduced Ptch function results in increased tumor growth, but that selective pressure appatently acts against complete Ptch2 ablation. CONCLUSIONS: We conclude that like Ptch1, Ptch2 exerts a tumor-suppressive function in BCC cells, and that after targeting of both paralogs, ligand-independent activation of the Hh pathway contributes to tumor growth.

Immunophenotypic analysis of the chronological events of tissue repair in aortic medial dissections.

Acute medial dissection of aorta can occur in the context of a sudden and unexpected death. For medico-legal reasons it is important to estimate as accurately the histological age of dissections. We evaluated the additional value of a systematic application of immunohistochemistry, compared with conventional histology only, in determining chronological steps of injury and repair. Thirty two paraffin embedded specimens of aortic dissection were retrospectively allocated to one of four defined stages: acute (I), subacute (II), early organizing (III) and scarring (IV) using Hematoxylin and Eosin and Elastica van Gieson stained sections. Subsequent immunohistochemically staining was performed with the following markers: (myeloperoxidase (neutrophils), citrullinated-Histone 3 (neutrophil extracellular traps), CD68 (macrophages), CD3 (T-cells), CD31 and CD34 (endothelial cells), and smooth muscle actin. Immune stained sections were scored semi-quantitatively. Histologically, five cases were identified as stage I, 16 as II, 7 as III and 4 as IV. Additional immunostaining for smooth muscle cells and endothelial cells altered the classification in 25% of cases (all in groups II and III). Immunostaining and semi-quantitative grading of involvement of neutrophils, macrophages and NETs also provided specific distribution patterns over the 4 age categories, including unexpected involvement of the peri adventitial fat tissue. In conclusion, it appears that semi-quantitative immunohistochemistry of resident vascular wall cells, inflammatory cells and NETS represents a useful adjunct in detailed histopathological grading of the chronological age of aortic dissections.

The change in circulating galectin-3 predicts absence of atrial fibrillation after thoracoscopic surgical ablation.

Aims: Galectin-3 (Gal-3) is an important mediator of cardiac fibrosis, particularly in heart failure. Increased Gal-3 concentration (Gal-3), associated with increased risk of developing atrial fibrillation (AF), may reflect atrial fibrotic remodelling underlying AF progression. We aimed to investigate whether the change in serum Gal-3 reflects alterations of the arrhythmogenic atrial substrate following thoracoscopic AF surgery, and predicts absence of AF. Methods and results: Consecutive patients undergoing thoracoscopic AF surgery were included. Left atrial appendages (LAAs) and serum were collected during surgery and serum again 6 months thereafter. Gal-3 was determined in tissue and serum. Interstitial collagen in the LAA was quantified using Picrosirius red staining. Ninety-eight patients (76% male, mean age 60 ± 9 years) underwent thoracoscopic surgery for advanced AF. Patients with increased Gal-3 after ablation compared to baseline had a higher recurrence rate compared to patients with decreased or unchanged Gal-3 (HR 2.91, P = 0.014). These patients more frequently had persistent AF, longer AF duration and thick atrial collagen strands (P = 0.049). At baseline, Gal-3 was similar between patients with and without AF recurrence: 14.8 ± 3.9 µg/L vs. 13.7 ± 3.7 µg/L, respectively in serum (P = 0.16); 94.5 ± 19.4 µg/L vs. 93.3 ± 30.8µg/L, respectively in atrial myocardium (P = 0.83). There was no correlation between serum Gal-3 and left atrial Gal-3 (P = 0.20), nor between serum Gal-3 and the percentage of fibrosis in LAA (P = 0.18). Conclusion: The change of circulating Gal-3, rather than its baseline value, predicts AF recurrence after thoracoscopic ablation. Patients in whom Gal-3 increases after ablation have a high recurrence rate reflecting ongoing profibrotic signalling, irrespective of arrhythmia continuation.

Discrepancy between the clinical and histopathologic diagnosis of soft tissue vascular malformations.

BACKGROUND: Soft tissue vascular malformations are generally diagnosed clinically, according to the International Society for the Study of Vascular Anomalies (ISSVA) classification. Diagnostic histopathologic examination is rarely performed. OBJECTIVE: We sought to evaluate the validity of the current diagnostic workup without routinely performed diagnostic histopathology. METHODS: We retrospectively determined whether there were discrepancies between clinical and histopathologic diagnoses of patients with clinically diagnosed vascular malformations undergoing therapeutic surgical resections in our center (2000-2015). Beforehand, a pathologist revised the histopathologic diagnoses according to the ISSVA classification. RESULTS: Clinical and histopathologic diagnoses were discrepant in 57% of 142 cases. In these cases, the pathologist indicated the diagnosis was not at all a vascular malformation (n = 24; 17%), a completely different type of vascular malformation (n = 26; 18%), or a partially different type with regard to the combination of vessel-types involved (n = 31; 22%). Possible factors associated with the discrepancies were both clinician-related (eg, diagnostic uncertainty) and pathology-related (eg, lack of immunostaining). LIMITATIONS: Retrospective analysis of a subgroup of patients undergoing surgery. CONCLUSION: The large discrepancy between clinical and histopathologic diagnoses raises doubt about the validity of the current diagnostic workup for vascular malformations. Clear clinical and histopathologic diagnostic criteria might be essential for a uniform diagnosis.

Sudden aortic death-proposal for a comprehensive diagnostic approach in forensic and in clinical pathology practice.

BACKGROUNDS: Aortic rupture or dissection as immediate cause of sudden death is encountered in forensic and clinical autopsy practice. Despite a common denominator of 'sudden aortic death' (SAD), we expect that in both settings the diagnostic workup, being either primarily legal or primarily disease related, differs substantially, which may affect the eventual diagnoses. METHODS: We retrospectively reviewed case records of deceased persons who fitted a diagnosis of SAD in the continuous autopsy cohorts in a forensic (Suisse) and a clinical setting (The Netherlands). Clinical characteristics, data from post-mortem imaging, tissue blocks for histological analysis and results of ancillary studies were reviewed for its presence and outcome. RESULTS: SAD was found in 7.7% in the forensic versus 2.2% in the clinical autopsies. In the forensic setting, autopsy was always combined with post-mortem imaging, showing variable outcome on detection of aortic disruption and/or pericardial bleeding. Histology of aorta was performed in 12/35 cases, mostly in the natural deaths. In the clinical setting, histology of the aorta was available in all cases, but post-mortem imaging in none. In both settings, underlying aortic disease was mostly cystic medial degeneration, atherosclerosis or a combination of both, with occasional rare unexpected diagnosis. Also in both, a genetic cause of aortic dissection was revealed in a minority (three cases). CONCLUSION: Sudden aortic death (SAD) is more commonly encountered in a forensic than in a clinical setting. Major differences in the approach of SAD between these settings coincide with similarities in causes of death and underlying diseases. To ensure a correct diagnosis, we recommend that the investigation of SAD includes a study of the medical history, a full autopsy with histology of major organs including aorta, and storage of material for toxicological and genetic testing. Post-mortem radiological examination, useful for documentation and screening purposes, is feasible as non-invasive alternative when autopsy is not possible, but cannot substitute a full autopsy.

Intravascular Lipiodol Presenting as an Atrial Mass.

A 68-year-old woman, previously treated with embolization of the thoracic duct with Lipiodol (an ethiodized oil injection) and cyanoacrylate glue (a topical tissue adhesive), was admitted with an asymptomatic mass in the inferior vena cava (IVC) and right atrium. The mass was surgically removed, and pathologic analysis revealed a Lipiodol-containing thrombus. To our knowledge, this is the first clinicopathologic report of Lipiodol-induced thrombus presenting as an intracavitary mass.

CD45 is a more sensitive marker than CD3 to diagnose lymphocytic myocarditis in the endomyocardium.

To diagnose lymphocytic myocarditis (LM), immunohistopathological examination of endomyocardial biopsies (EMBs) is used with a cutoff value of at least 14 leukocytes per mm2, composed of CD3- and CD68-positive cells. We hypothesized that a more common leukocyte marker, CD45, instead of CD3 could increase the diagnostic sensitivity. Hearts of mice with acute viral myocarditis (n = 9) and of controls (n = 7) and the EMB sampling area of the left ventricular posterior wall (LVPW) obtained from autopsied hearts of patients diagnosed with LM (n = 18) and controls (n = 6) were stained with anti-CD68, anti-CD3, and anti-CD45. When applying the threshold of at least 14 leukocytes per mm2, 33% of the mice would be diagnosed with LM with the use of CD3+CD68 and 89% with the use of CD45+CD68. In the EMB sampling area of autopsied hearts, using the cutoff value of at least 14 leukocytes per mm2, CD3+CD68 could only confirm 17% of the diagnosis of LM, whereas CD45+CD68 could confirm 50% of the LM cases. Moreover, we compared inflammation in the EMB sampling area of the LVPW to the remaining myocardium of the LVPW and observed a significant increase of CD45+CD68 cells per mm2 in patients with LM. In conclusion, the use of the common leukocyte marker CD45 increases the sensitivity of the diagnosis of LM. Furthermore, the inflammatory infiltrate in the EMB sampling area is significantly increased compared with the remaining LVPW, indicating that the sampling area constitutes the highest chance for histological diagnosis of LM.

Carotid plaque fissure: An underestimated source of intraplaque hemorrhage.

BACKGROUND AND AIMS: Plaque fissuring, a phenomenon morphologically distinct from the classical rupture of a thinned fibrous cap, has not been well characterized in carotid atherosclerosis. The aim of this study was to establish the prevalence of plaque fissures in advanced carotid plaques with an otherwise intact luminal surface, and to determine whether they might be a source of intraplaque hemorrhage (IPH). METHODS: We evaluated 244 surgically intact, 'en bloc' embedded, serially sectioned carotid endarterectomy specimens and included only those plaques with a grossly intact luminal surface. RESULTS: Among the 67 plaques with grossly intact luminal surface, cap fissure was present in 39 (58%) plaques. A total of 60 individual fissures were present, and longitudinally mean fissure length was 1.3 mm. Most fissures were found distal to the bifurcation (63%), proximal to the stenosis (88%), and in the posterior (opposite the flow divider) or lateral quadrants (80%). 36% of the fissures remained in the superficial third of the plaque. 52% extended from the lumen surface to the middle third of the plaque and 12% reached the outer third of the plaque on cross section. Fissures often occurred between two tissue planes and were connected to IPH (fresh: 63%; any type: 92%) and calcifications (43%). No correlation was found with patient characteristics such as symptom status, carotid stenosis, hypertension, diabetes, smoking and medications (statins or antiplatelet agents). CONCLUSIONS: Plaque fissures are common in advanced carotid plaques with an otherwise grossly intact luminal surface and are associated with fresh intraplaque hemorrhage. As they occur on the interface between plaque components with different mechanical properties, further biomechanical studies are needed to unravel the underlying failure mechanisms.

Lymph vessels: the forgotten second circulation in health and disease.

The lymphatic circulation is still a somewhat forgotten part of the circulatory system. Despite this, novel insights in lymph angiogenesis in health and disease, application of immune markers for lymphatic growth and differentiation and also the introduction of new imaging techniques to visualize the lymphatic circulation have improved our understanding of lymphatic function in both health and disease, especially in the last decade. These achievements yield better understanding of the various manifestations of lymph oedemas and malformations, and also the patterns of lymphovascular spread of cancers. Immune markers that recognize lymphatic endothelium antigens, such as podoplanin, LYVE-1 and Prox-1, can be successfully applied in diagnostic pathology and have revealed (at least partial) lymphatic differentiation in many types of vascular lesions.

Consensus statement on surgical pathology of the aorta from the Society for Cardiovascular Pathology and the Association For European Cardiovascular Pathology: II. Noninflammatory degenerative diseases - nomenclature and diagnostic criteria.

Surgical aortic specimens are usually examined in Pathology Departments as a result of treatment of aneurysms or dissections. A number of diseases, genetic syndromes (Marfan syndrome, Loeys-Dietz syndrome, etc.), and vasculopathic aging processes involved in vascular injury can cause both distinct and nonspecific histopathologic changes with degeneration of the media as a common denominator. Terminology for these changes has varied over time leading to confusion and inconsistencies. This consensus document has established a revised, unified nomenclature for the variety of noninflammatory degenerative aortic histopathologies seen in such specimens. Older terms such as cystic medial necrosis and medionecrosis are replaced by more technically accurate terms such as mucoid extracellular matrix accumulation (MEMA), elastic fiber fragmentation and/or loss, and smooth muscle cell nuclei loss. A straightforward system of grading is presented to gauge the extent of medial degeneration and synoptic reporting tables are provided. Herein we present a standardized nomenclature that is accessible to general pathologists and useful for future publications describing these entities.