Clinical and molecular practice of European thoracic pathology laboratories during the COVID-19 pandemic. The past and the near future.

BACKGROUND: This study evaluated the consequences in Europe of the COVID-19 outbreak on pathology laboratories orientated toward the diagnosis of thoracic diseases. MATERIALS AND METHODS: A survey was sent to 71 pathology laboratories from 21 European countries. The questionnaire requested information concerning the organization of biosafety, the clinical and molecular pathology, the biobanking, the workload, the associated research into COVID-19, and the organization of education and training during the COVID-19 crisis, from 15 March to 31 May 2020, compared with the same period in 2019. RESULTS: Questionnaires were returned from 53/71 (75%) laboratories from 18 European countries. The biosafety procedures were heterogeneous. The workload in clinical and molecular pathology decreased dramatically by 31% (range, 3%-55%) and 26% (range, 7%-62%), respectively. According to the professional category, between 28% and 41% of the staff members were not present in the laboratories but did teleworking. A total of 70% of the laboratories developed virtual meetings for the training of residents and junior pathologists. During the period of study, none of the staff members with confirmed COVID-19 became infected as a result of handling samples. CONCLUSIONS: The COVID-19 pandemic has had a strong impact on most of the European pathology laboratories included in this study. Urgent implementation of several changes to the organization of most of these laboratories, notably to better harmonize biosafety procedures, was noted at the onset of the pandemic and maintained in the event of a new wave of infection occurring in Europe.

[Clinical autopsies in Switzerland : A status report]. / Klinische Obduktionen in der Schweiz : Ein Statusbericht.

BACKGROUND: The number of autopsies has been steadily declining worldwide over the past decades. The reasons for this are diverse. Legislation regarding opposition and consent rules does not appear to have had a significant impact on the autopsy rates. Above all, structural causes and the attitude of the medical profession are the reasons for this decline. The main argument for a high autopsy rate is the identification of diagnostic errors; however, diagnostic discrepancies are relatively independent of the rate of autopsies performed. At the University Hospital (UniversitätsSpital) Zurich it could be shown in a study that from 1972-2002 the frequency of relevant diagnostic discrepancies (classes I and II) decreased from 30% to 7%. OBJECTIVE: The aim of this article is to present the necessity of a stable autopsy rate and to examine the situation of the autopsy in Switzerland. MATERIAL AND METHODS: For this purpose, the importance of autopsies in the fields of quality assurance of medical diagnostics, cancer statistics, medical research as well as further education of doctors in Switzerland is shown. Efforts are being made by the pathologists to counteract the declining autopsy rates. RESULTS AND DISCUSSION: Declining autopsy numbers have a significant influence on cancer statistics. The rate of newly discovered tumors in autopsies in Switzerland decreased from 42% in 1980 to 17% in 2010. Pediatric autopsies are an important tool for quality assurance of medical diagnostics in neonatology and pediatrics in Switzerland, but the rate of autopsies carried out is also declining. Postmortem magnetic resonance imaging (MRI) examinations (virtopsy) could increase the acceptance of the parents for an autopsy in the future. Autopsies make an important contribution in research and in documentation of therapy-associated side effects and they are an important component of further education of the upcoming medical generations.

[The pathology of adverse events with immune checkpoint inhibitors]. / Pathologie der Nebenwirkungen von Immune-Checkpoint-Inhibitoren.

BACKGROUND: Immunotherapy has gained importance with the development of new effective cancer treatments. Immune checkpoint inhibitors (ICI) are monoclonal antibodies that promote T­cell mediated tumor immune rejection. Checkpoint blockade also carries the risk of inducing autoimmune reactions ("immune related adverse events", irAEs). The diagnosis and classification of irAEs constitute a new and important field in pathology. AIM: Practice-oriented review of the diagnosis and classification of irAEs. MATERIALS AND METHODS: Structured, selective literature review based on PubMed und UpToDate ® online. RESULTS: The most common irAEs affect the skin, the gastrointestinal tract, the liver, and the respiratory system. The correct diagnosis and classification of irAEs by an interdisciplinary care team is essential for appropriate therapy and the prevention of long-term sequelae. Other important irAEs affect the endocrine organs, the heart, the joints, the kidneys and the nervous system. Because of their rarity and/or limited options for bioptic diagnosis, only limited data on the morphology and pathophysiology of these irAEs are currently available. Autopsies carried out after ICI therapy constitute an important element of quality control and allow better documentation of the incidence and pathogenesis of irAEs. DISCUSSION: Pathology plays a central role in the diagnosis and treatment of irAEs. Future studies may contribute to a better mechanistic understanding of irAEs for individualized knowledge-based risk assessment.

Endometrioid endometrial adenocarcinoma: an increase of G3 cancers?

PURPOSE: Endometrial cancer can be divided into two types: endometrioid Type 1 (G1, G2) has a hormonal driven etiology, while Type 2 is more aggressive (G3 endometrioid, clear cell and serous cancer type) and estrogen independent. We noticed an increase of more aggressive G3 endometrioid endometrial adenocarcinomas. This observation is of relevance for daily clinical practice because therapy depends on the histopathological grading and myometrial invasion. G3 cancers or myometrial invasion of more than 50% should be hysterectomized including bilateral adnexectomy with pelvine and paraaortal lymphadenectomy. In G1/G2 and lower infiltration levels, hysterectomy with adnexectomy without lymphadenectomy is sufficient. METHODS: Data of the ASF Statistic were used to analyze the changes in the incidences of patients with endometrioid cancer, grading groups and their first diagnosed stages between 2006 and 2014. RESULTS: 2611 patients, with 243-341 women per year, were analyzed. The number of diagnosed G1 tumors increased from 25 to 37% and the G3 tumors from 18 to 32%, whereas the G2 cancers decreased from 58 to 31%. Despite the rise of G3 tumors, an increase in age at diagnosis was not observed. The proportions of initial diagnosed stages (FIGO I-IV) in each grading remained constant over time. CONCLUSION: Potential consequences in treatment recommendations and prognosis urge attention to the detected increase of G3 endometrioid cancers.

Helicobacter-negative gastritis: polymerase chain reaction for Helicobacter DNA is a valuable tool to elucidate the diagnosis.

BACKGROUND: Helicobacter-negative gastritis has been increasingly reported. Molecular techniques as the polymerase chain reaction (PCR) may detect bacterial DNA in histologically negative gastritis. AIM: To evaluate of Helicobacter PCR in gastric biopsies for the daily diagnostics of Helicobacter-negative gastritis. METHODS: Over a 5-year period, routine biopsies with chronic gastritis reminiscent of Helicobacter infection, but negative by histology, were tested by using a H. pylori specific PCR. Subsequently, PCR-negative samples were re-evaluated using PCR for other Helicobacter species. RESULTS: Of the 9184 gastric biopsies, 339 (3.7%) with histological-negative gastritis and adequate material were forwarded to PCR analysis for H. pylori and 146 (43.1%) revealed a positive result. In 193 H. pylori DNA-negative biopsies, re-analysis using PCR primers for other Helicobacter species, revealed further 23 (11.9%) positive biopsies, including 4 (2.1%) biopsies with H. heilmannii sensu lato. PCR-positive biopsies showed a higher overall inflammatory score, more lymphoid follicles/aggregates and neutrophils (P < 0.05). No Helicobacter DNA was found in control biopsies of 48 patients with neither primer set (P < 0.0001). In 274 patients with an endoscopic description, detection of H. pylori DNA was associated with ulcers and erosions (P < 0.01). Over all, in 339 histologically-negative gastric biopsies, Helicobacter DNA was detected in 169 (49.9%) samples with at least one primer set. CONCLUSION: Molecular testing offers a sensitive and specific diagnosis to a selected group of patients, in whom adequate searches for bacteria by conventional histology have resulted in the unsatisfactory diagnosis of H. pylori-negative gastritis.

European consensus on the histopathology of inflammatory bowel disease.

The histologic examination of endoscopic biopsies or resection specimens remains a key step in the work-up of affected inflammatory bowel disease (IBD) patients and can be used for diagnosis and differential diagnosis, particularly in the differentiation of UC from CD and other non-IBD related colitides. The introduction of new treatment strategies in inflammatory bowel disease (IBD) interfering with the patients' immune system may result in mucosal healing, making the pathologists aware of the impact of treatment upon diagnostic features. The European Crohn's and Colitis Organisation (ECCO) and the European Society of Pathology (ESP) jointly elaborated a consensus to establish standards for histopathology diagnosis in IBD. The consensus endeavors to address: (i) procedures required for a proper diagnosis, (ii) features which can be used for the analysis of endoscopic biopsies, (iii) features which can be used for the analysis of surgical samples, (iv) criteria for diagnosis and differential diagnosis, and (v) special situations including those inherent to therapy. Questions that were addressed include: how many features should be present for a firm diagnosis? What is the role of histology in patient management, including search for dysplasia? Which features if any, can be used for assessment of disease activity? The statements and general recommendations of this consensus are based on the highest level of evidence available, but significant gaps remain in certain areas.

[Motility disorders of the esophagus]. / Motilitätsstörungen des Ösophagus.

Motility disorders of the esophagus comprise a heterogeneous spectrum of diseases. Primary malformations of the esophagus are now amenable to improved surgical and gastroenterological therapies; however, they often lead to persistent long-term esophageal dysmotility. Achalasia originates from impaired relaxation of the gastroesophageal sphincter apparatus. Systemic diseases may give rise to secondary disorders of esophageal motility. A number of visceral neuromuscular disorders show an esophageal manifestation but aganglionosis rarely extends into the esophagus. The growing group of myopathies includes metabolic and mitochondrial disorders with increasing levels of genetic characterization and incipient emergence of therapeutic strategies. Esophagitis with an infectious etiology causes severe dysmotility particularly in immunocompromised patients. Immunologically mediated inflammatory processes involving the esophagus are increasingly better understood. Finally, rare tumors and tumor-like lesions may impair esophageal motor function.

Colonic mast cells in controls and slow transit constipation patients.

BACKGROUND: There is recent evidence that mast cells may play important roles in the gut, especially concerning visceral hypersensitivity and motor activity. However, most data are only available for clinical conditions characterised by diarrhoea, where MC have chiefly investigated in the mucosal layer of the colon and there is almost no information concerning constipation. AIM: To investigate mast cells distribution in all colonic layers in controls and severely constipated patients. METHODS: Full-thickness specimens from colons of patients undergoing surgery for slow transit constipation (n=29), compared with controls, were obtained and the number of mast cells (evaluated by specific monoclonal antibodies) counted as a whole and in single colonic segments (caecum, ascending, transverse, descending and sigmoid). RESULTS: Compared with controls, constipated patients revealed significantly higher number of mast cells, both as overall number and in single colonic segments. The distribution of mast cells resulted fairly homogeneous in the various segment of the large bowel, in both controls and patients, and no significant difference in the percentage of degranulated cells was found between groups. CONCLUSIONS: Colonic mast cells display a homogeneous distribution within the viscus. This cell population is shown to increase in severely constipated patients, which might represent a mechanism trying to compensate for the impaired propulsive activity of these patients.

LANA-1, Bcl-2, Mcl-1 and HIF-1alpha protein expression in HIV-associated Kaposi sarcoma.

Human herpesvirus 8 (HHV8) is necessary for Kaposi sarcoma (KS) to develop, but whether the tissue viral load is a marker of KS progression is still unclear. Little is known about the level of expression of apoptosis-regulating proteins and of hypoxia-inducible factors (HIFs) in KS tumour cells relative to HHV8 expression. We therefore investigated the expression of the latency-associated nuclear antigen (LANA-1) of HHV8, Bcl-2, Mcl-1, Bax, Bcl-xL, caspase 3 and HIF-1alphain KS tissue specimens at different stages of the disease. The expression of these proteins was evaluated immunohistochemically using tissue microarrays (TMAs) in tissue specimens from 245 HIV-positive patients at different stages of the disease. Both LANA-1 and HIF-1alpha were expressed in KS biopsies taken at different stages, but their level increased throughout tumour progression. Additionally, the levels of Bcl-2 and Mcl-1 were higher in visceral KS lesions compared to levels observed in cutaneous and mucosal KS. This study demonstrates that late tumour stages of KS in tissues from HIV-positive patients are associated with high levels of LANA-1, HIF-1alpha and of the anti-apoptotic proteins, Bcl-2 and Mcl-1. Finally, the expression of these proteins can be potentially used as a tissue biomarker in defining patients with a higher risk of disease progression.

Is pseudomelanosis coli a marker of colonic neuropathy in severely constipated patients?

AIMS: To study relationships between the number of pseudomelanosis coli cells and that of colonic enteric neurons and interstitial cells of Cajal, which are significantly reduced compared with controls in severely constipated patients. Pseudomelanosis coli is frequent in patients using anthraquinone laxatives. It is not known whether the prolonged use of these compounds damages the enteric nervous system in constipated patients. PATIENTS AND METHODS: The relationship between the number of pseudomelanosis coli cells and that of colonic enteric neurons (as well as that of apoptotic enteric neurons) and of interstitial cells of Cajal was assessed by histological and immunohistochemical methods in 16 patients with chronic use of anthraquinone laxatives undergoing surgery for severe constipation unresponsive to medical treatment. No relationship was found between the number of pseudomelanosis coli cells and that of enteric neurons (and that of the apoptotic ones), nor of interstitial cells of Cajal, in either the submucosal or the myenteric plexus. CONCLUSION: The use of anthraquinone laxatives, leading to the appearance of pseudomelanosis coli, is probably not related to the abnormalities of the enteric nervous system found in severely constipated patients.

The role of glial cells and apoptosis of enteric neurones in the neuropathology of intractable slow transit constipation.

BACKGROUND: Idiopathic slow transit constipation is one of the most severe and often intractable forms of constipation. As motor abnormalities are thought to play an important pathogenetic role, studies have been performed on the colonic neuroenteric system, which rules the motor aspects of the viscus. AIMS: We hypothesised that important neuropathological abnormalities of the large bowel are present, that these are not confined to the interstitial cells of Cajal and ganglion cells, and that the previously described reduction of enteric neurones, if confirmed, might be related to an increase in programmed cell death (apoptosis). PATIENTS AND METHODS: Surgical specimens from 26 severely constipated patients were assessed by conventional and immunohistochemical methods. Specific staining for enteric neurones, glial cells, interstitial cells of Cajal, and fibroblast-like cells associated with the latter were used. In addition, gangliar cell apoptosis was evaluated by means of indirect and direct techniques. Data from patients were compared with those obtained in 10 controls. RESULTS: Severely constipated patients displayed a significant decrease in enteric gangliar cells, glial cells, and interstitial cells of Cajal. Fibroblast-like cells associated with the latter did not differ significantly between patients and controls. Patients had significantly more apoptotic enteric neurones than controls. CONCLUSION: Severely constipated patients have important neuroenteric abnormalities, not confined to gangliar cells and interstitial cells of Cajal. The reduction of enteric neurones may in part be due to increased apoptotic phenomena.

[Fever, malaise and new onset mitral valve insufficiency. Subacute Streptococcus bovis mitral valve endocarditis ]. / Fieber, Leistungsknick und neu aufgetretene Mitralinsuffizienz. Subakute Mitralklappen-Endocarditis mitStreptococcus bovis.

A 62-year-old patient with low grade fever, fatigue, arthralgia and newly discovered mitral regurgitation was diagnosed with subacute endocarditis. Streptococcus bovis grew from all six blood culture bottles. Streptococcus bovis is known to be associated with gastrointestinal neoplasias. Therefore a colonoscopy was performed and two polyps were removed. Histological analysis revealed a tubulovillous adenoma and a serrated adenoma. Colonoscopy is mandatory for all patients with Streptococcus bovis endocarditis even without any symptoms for colorectal neoplasia. The significance of Streptococcus bovis for the carcinogenesis of colorectal neoplasias and the possible alternative pathway for colorectal carcinomas through serrated adenomas will be discussed.

Effect of buffered formalin on amplification of DNA from paraffin wax embedded small biopsies using real-time PCR.

BACKGROUND: The isolation of good quality DNA from routinely fixed and processed biopsy samples is crucial for the success of subsequent molecular analysis. AIMS: To compare the amount of beta actin DNA extracted from upper gastrointestinal tract biopsies fixed in buffered and unbuffered formalin. METHODS: Amounts of beta actin DNA extracted from forceps biopsies of the upper gastrointestinal tract fixed in unbuffered (n = 22) and buffered formalin (n = 16) were estimated by quantitative real-time polymerase chain reaction. RESULTS: The yield of beta actin DNA was significantly higher in biopsies fixed in buffered formalin than in those fixed in unbuffered formalin (median 2.8 x 10(4) and 5.3 x 10(2) DNA molecules, respectively; p < 0.005). Furthermore, fixation in buffered formalin led to a more reproducible DNA extraction, as indicated by the coefficient of variation (1.0 and 2.2, respectively). CONCLUSIONS: This study indicates that tissue samples should be fixed in buffered formalin to facilitate the use of molecular pathology analysis in routine biopsy material.

HHV-8 DNA sequences in the peripheral blood and skin lesions of an HIV-negative patient with multiple eruptive dermatofibromas: implications for the detection of HHV-8 as a diagnostic marker for Kaposi's sarcoma.

BACKGROUND: Multiple eruptive dermatofibroma (MEDF) is a rare disorder seen in immunocompromised patients, simulating Kaposi's sarcoma (KS). Whereas KS is strongly associated with human herpesvirus 8 (HHV-8), the virus has never been detected in MEDF until now. OBJECTIVE: To present a patient with MEDF who showed no signs of immunodeficiency but was seropositive for HHV-8 antibodies and demonstrated HHV-8 DNA both in the peripheral blood and lesional skin of MEDF. METHODS: Clinical, histological and serological investigations were performed as well as polymerase chain reaction (PCR) studies and in situ hybridization (ISH). RESULTS: A 35-year-old white man with suspected KS was referred for evaluation of multiple pigmented nodules and patches. Biopsies revealed features of dermatofibroma, superficial fibrosing dermatitis and scar. One of the nodular lesions harbored HHV-8 DNA sequences. A faint amplification product was detected in the superficial fibrosing dermatitis lesion, while no HHV-8 sequences were found in normal skin and scar. Whole-blood samples and serum were positive for HHV-8. None of the skin lesions shown to harbor HHV-8 DNA sequences by nested PCR displayed a signal for HHV-8 RNA by ISH. Repetitive peripheral blood examinations did not reveal any serum antibodies against or antigens of HIV. Serum antibodies against the HHV-8 capsid antigen orf 65.2 were detected. CONCLUSION: Results of PCR studies and ISH indicate that the presence of HHV-8 in the lesional tissue was probably blood-borne due to viremia and not due to viral replication in tumor cells. The presence of HHV-8 is not fully restricted to KS. The differential diagnosis of KS and its simulators should be based on an integrative analysis of all available clinicopathological and molecular data and should not rely exclusively or predominantly on the presence or absence of HHV-8.

Simultaneous bilateral spontaneous pneumothorax in a patient with recurrent, extraosseous multiple myeloma.

A patient with simultaneous bilateral spontaneous pneumothorax (SBSP) due to pulmonary and pleural manifestations of recurrent multiple myeloma is presented. The patient died in shock of unknown cause. The diagnosis was suspected from pleural fluid examination showing an exudate with numerous plasmocytes. Macroscopically and histologically, the visceral organs and the bone marrow were infiltrated with multiple monoclonal proliferations of plasma cells staining positively for IgG and lambda chains. SBSP is a rare condition and may be caused by trauma, parenchymal lung disease, infections, or neoplasms. This is the first report of SBSP caused by pleuropulmonary infiltration of multiple myeloma.

Renal pathology and premortem clinical presentation of Caucasian patients with AIDS: an autopsy study from the era prior to antiretroviral therapy.

PRINCIPLES: Renal disease in patients with HIV infection is becoming increasingly frequent. A particular form of HIV-associated nephropathy (HIVAN) has been found in patients of predominantly African-American and Hispanic origin. However, only limited data are available on renal pathology and premortem clinical presentation of kidney disease in Caucasian patients with AIDS. METHODS: To determine the prevalence, clinical presentation and aetiology of renal disease in Caucasian patients with AIDS at the time of death we have performed a prospective autopsy study with 239 patients who died of AIDS between 1981 and 1989. None of these patients had received HIV-specific antiretroviral therapy. Autopsies and histological analyses were performed on the basis of a standardised protocol. Clinical and laboratory data were gathered according to a uniform questionnaire. RESULTS: 95% of patients were of Caucasian race. 75% of all patients had extended AIDS (stage IV). Clinical signs of nephropathy prior to death were found in 36% of patients, including proteinuria (18%), abnormal urinary sediment (19.5%), and renal insufficiency (11%). Histopathological lesions were present in 43% of the autopsies, with two or more distinct structural lesions in 12.5% of patients. Of the pathological findings 28% were glomerular or vascular, 33% were non-glomerular, and 29% were combined lesions. The remaining 10% were renal infiltrations of infectious agents or neoplastic tissue. The most common findings were ischaemic changes and vascular scars (18% of patients), as well as pyelo- and interstitial nephritides (12.2%). Importantly, FSGS was present in only 1.7% of patients, and only a single African patient had classical HIVAN. CONCLUSIONS: Renal involvement in HIV disease is very common at the time of death among patients of Caucasian origin. However, classical HIV-associated nephropathy is absent in this population. These findings suggest that kidney disease affects all races and supports the hypothesis that HIVAN is specifically related to non-Caucasian ethnicity. The results reflect renal disease unaffected by HIV-specific antiretroviral therapy.