[Genetic diffuse cystic lung disease in adults]

Multiple cystic lung diseases comprise a wide range of various diseases, some of them of genetic origin. Lymphangioleiomyomatosis (LAM) is a disease occurring almost exclusively in women, sporadically or in association with tuberous sclerosis complex (TSC). Patients with LAM present with lymphatic complications, renal angiomyolipomas and cystic lung disease responsible for spontaneous pneumothoraces and progressive respiratory insufficiency. TSC and LAM have been ascribed to mutations in TSC1 or TSC2 genes. Patients with TSC are variably affected by cutaneous, cognitive and neuropsychiatric manifestations, epilepsy, cerebral and renal tumors, usually of benign nature. Birt-Hogg-Dubé syndrome is caused by mutations in FLCN encoding folliculin. This syndrome includes lung cysts of basal predominance, cutaneous fibrofolliculomas and various renal tumors. The main complications are spontaneous pneumothoraces and renal tumors requiring systematic screening. The mammalian target of rapamycin (mTOR) pathway is involved in the pathophysiology of TSC, sporadic LAM and Birt-Hogg-Dubé syndrome. MTOR inhibitors are used in LAM and in TSC while Birt-Hogg-Dubé syndrome does not progress towards chronic respiratory failure. Future challenges in these often under-recognized diseases include the need to reduce the delay to diagnosis, and to develop potentially curative treatments. In France, physicians can seek help from the network of reference centers for the diagnosis and management of rare pulmonary diseases.

Real-world EGFR testing practices for non-small-cell lung cancer by thoracic pathology laboratories across Europe

BACKGROUND

Testing for epidermal growth factor receptor (EGFR) mutations is an essential recommendation in guidelines for metastatic non-squamous non-small-cell lung cancer, and is considered mandatory in European countries. However, in practice, challenges are often faced when carrying out routine biomarker testing, including access to testing, inadequate tissue samples and long turnaround times (TATs).

MATERIALS AND METHODS

To evaluate the real-world EGFR testing practices of European pathology laboratories, an online survey was set up and validated by the Pulmonary Pathology Working Group of the European Society of Pathology and distributed to 64 expert testing laboratories. The retrospective survey focussed on laboratory organisation and daily EGFR testing practice of pathologists and molecular biologists between 2018 and 2021.

RESULTS

TATs varied greatly both between and within countries. These discrepancies may be partly due to reflex testing practices, as 20.8% of laboratories carried out EGFR testing only at the request of the clinician. Many laboratories across Europe still favour single-test sequencing as a primary method of EGFR mutation identification; 32.7% indicated that they only used targeted techniques and 45.1% used single-gene testing followed by next-generation sequencing (NGS), depending on the case. Reported testing rates were consistent over time with no significant decrease in the number of EGFR tests carried out in 2020, despite the increased pressure faced by testing facilities during the COVID-19 pandemic. ISO 15189 accreditation was reported by 42.0% of molecular biology laboratories for single-test sequencing, and by 42.3% for NGS. 92.5% of laboratories indicated they regularly participate in an external quality assessment scheme.

CONCLUSIONS

These results highlight the strong heterogeneity of EGFR testing that still occurs within thoracic pathology and molecular biology laboratories across Europe. Even among expert testing facilities there is variability in testing capabilities, TAT, reflex testing practice and laboratory accreditation, stressing the need to harmonise reimbursement technologies and decision-making algorithms in Europe.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, full version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, short version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

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.

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Biosafety measures used in the first wave of the COVID-19 crisis were heterogeneous in 53 European pathology laboratories.

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A dramatic decrease of the workload in pathology laboratories was noted.

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No case of healthcare workers contaminated with SARS-CoV-2 associated with samples handling was identified.

A New Hypo/Oligodontia Syndrome

Dental agenesis is either syndromic or non-syndromic. Here, we describe a familial case with Carvajal/Naxos syndrome associating woolly hair, palmoplantar keratoderma, and biventricular dilated cardiomyopathy. In addition to these signs, all three affected family members had hypo/oligodontia ranging from absence of the lower left second molar to 15 missing teeth, the typical pattern of oligodontia being absent 2nd premolars and absent 2nd and 3rd molars. Mutation screening in the desmoplakin gene ( DSP) revealed a de novo missense mutation (c.1790 C>T, p.Ser597Leu) changing a serine residue conserved in all vertebrates. In addition, this variation was absent from 100 control DNA samples. There were no mutations in the plakoglobin gene. This familial case report and two other previous reports demonstrate that autosomal-dominant mutations in the DSP gene are associated with hypo/oligodontia in the setting of Carvajal/Naxos syndrome. This study suggests that dentists discovering oligo/hypodontia should screen for woolly hair and palmoplantar keratoderma because of the probable cardiac involvement with an inherent high risk of severe cardiomyopathy. In addition, this study reveals the role of desmosomes in the development of teeth and suggests that other genes encoding proteins of the desmosome could be involved in oligo/hypodontia.

Link between immune cell infiltration and mitochondria-induced cardiomyocyte death during acute cardiac graft rejection

Acute cardiac graft rejection (ACGR) is associated with cardiomyocyte apoptosis. We investigated the respective role of the Fas/FasL and mitochondrial permeability transition pore (mPTP) pathways in cardiomyocyte apoptosis accompanying ACGR. Heterotopic cardiac transplantations were performed in 7-9-week old C57BL6 or C3H mice. Wild type or Fas-deficient (lpr) mice underwent syngeneic (GS) or allogeneic (GA) transplantation, and received either saline or NIM811, a specific inhibitor of the mPTP. At day 5, we assessed ACGR by histology, cardiomyocyte apoptosis by caspase-3 activity and cytochrome c release, Ca(2+)-induced mPTP opening by a potentiometric approach, and expression of Fas, FasL, TNFalpha, perforin, granzyme using RT-PCR. Myocardial infiltration of CD8(+) T lymphocytes was performed by immunohistochemistry. Allogenic transplantation increased infiltration of inflammatory cells, upregulated FasL, perforin, granzyme, and TNFalpha, favored Ca(2+)-induced mPTP opening and increased caspase-3 activity and cytochrome c release in WT grafts. NIM811, but not Fas-deficiency, significantly reduced all these effects. NIM811 also limited infiltration of CD8(+) into WT and lpr transplants. These data suggest that the mPTP pathway plays a major role in cardiomyocyte apoptosis associated with ACGR. Inhibition of mPTP opening may attenuate cardiomyocyte apoptosis either directly or indirectly via a limitation of CD8(+) T-cell activation.

[The "intra-cordal polyp": a clinical alternative to recognize?]

The vocal cord polyp is an inflammatory false tumour of the larynx. It is characterized mainly by the specific existence of fibrinous exsudats organized in loose network or mounds, surrounded by newly formed vascular slits. The epithelium covering the polyp is usually more or less impaired.

CLINICAL CASES

The authors report two adult patients among whom the initial presentation in video-stroboscopy was that of an intracordal lesion of a cystic type, however; with unusual characteristics (purplish color, angiomatous aspect). The surgery consisted of a cordotomy, the surface epithelium appearing normal. After dissection, the two lesions seemed to be presenting the typical aspect of fibrinoïd mound of a polyp, observation confirmed by the anatomo-pathological study. In these cases, the resection was finally carried out with no mucous loss.

CONCLUSION

The particular etiopathogeny of these lesions is been discussed. The treatment, medical and of rehabilitation could achieve a partial recovery. In the event of surgery, an access to the lesion through a cordotomy and not directly by removal with microcissors is advised.

Fas-independent mitochondrial damage triggers cardiomyocyte death after ischemia-reperfusion

The Fas/Fas ligand and mitochondria pathways have been involved in cell death in several cell types. We combined the genetic inactivation of the Fas receptor (lpr mice), on the one hand, to the pharmacological inhibition of the mitochondrial permeability transition pore (mPTP), on the other hand, to investigate which of these pathways is predominantly activated during prolonged ischemia-reperfusion. Anesthetized C57BL/6JICO (control) and C57BL/6-lpr mice were pretreated with either saline or cyclosporin A (CsA; 40 mg/kg, 3 times a day), an inhibitor of the mPTP, and underwent 25 min of ischemia and 24 h of reperfusion. After 24 h of reperfusion, hearts were harvested: infarct size was assessed by 2,3,5-triphenyltetrazolium chloride staining, myocardial apoptosis by caspase 3 activity, and mitochondrial permeability transition by Ca2+-induced mPTP opening using a potentiometric approach. Infarct size was comparable in untreated control and lpr mice, ranging from 77 +/- 5% to 83 +/- 3% of the area at risk. CsA significantly reduced infarct size in control and lpr hearts. Control and lpr hearts exhibited comparable increase in caspase 3 activity that averaged 57 +/- 18 and 49 +/- 5 pmol x min(-1) x mg(-1), respectively. CsA treatment significantly reduced caspase 3 activity in control and lpr hearts. The Ca2+ overload required to open the mPTP was decreased to a similar extent in lpr and controls. CsA significantly attenuated Ca2+-induced mPTP opening in both groups. Our results suggest that the Fas pathway likely plays a minor role, whereas mitochondria are preferentially involved in mice cardiomyocyte death after a lethal ischemia-reperfusion injury.

Identification and Characterization of Two Genes (MIP-1β, VE-CADHERIN) Implicated in Acute Rejection in Human Heart Transplantation

Background— Genes and mechanisms of action involved in human acute rejection after allogeneic heart transplantation remain to be elucidated. The use of a murine allograft model in tandem with cDNA arrays and quantitative real-time polymerase chain reaction (Q-PCR) can greatly help in identifying key genes implicated in human heart acute rejection.

Methods and Results— Hearts from Balb/c mice were either not transplanted or transplanted heterotopically in the abdomen of Balb/c (isografts) and C57BL/6 (allografts) mice. Histological analysis showed acute rejection only in allografts. Total RNA was extracted from isografts (n=3), allografts (n=4), and not transplanted hearts (n=4); reverse transcribed; and labeled with P32. Each probe was hybridized to cDNA macroarrays. Eight genes were overexpressed and 7 genes were underexpressed in allografts compared with isografts. Macrophage inflammatory protein-1β (MIP-1β), an overexpressed gene, and VE-cadherin, an underexpressed gene, were validated by immunohistochemistry and Q-PCR in the murine models. Genes of interest, validated in the 3 murine groups, were then investigated in human heart tissues. Immunohistochemistry and Q-PCR performed on endomyocardial biopsies after heart transplantation showing no rejection (n=10) or grade IB (n=10) or IIIA (n=10) rejection, according to International Society of Heart and Lung Transplantation criteria, confirmed the results obtained from the murine model.

Conclusions— We have demonstrated that the upregulation of MIP-1β and downregulation of VE-cadherin may strongly participate in human acute heart rejection.

Thymic carcinoma: a clinicopathological and immunohistological study of 19 cases

AIMS

To study 19 cases of primary thymic carcinoma in order to define the clinicopathological features and the precise histochemical profile of this rare and heterogeneous group of tumours of the anterior mediastinum.

METHODS AND RESULTS

The study group consisted of 13 males and six females, with a mean age of 58.5 years (range 29-75 years). Superior vena cava syndrome and chest pain were the main presenting symptoms. Three patients were asymptomatic. No patient had myasthenia gravis. Six different histological types were identified: neuroendocrine tumours (six patients), epidermoid carcinoma (five patients), sarcomatoid carcinoma (three patients), lymphoepithelioma-like carcinoma (two patients), mucoepidermoid carcinoma, clear cell carcinoma, and undifferentiated carcinoma (one patient each). The clear cell carcinoma was associated with a thymic cyst. No association with thymoma was observed. Surgical resection, performed in 10 cases, was complete in two. Sixteen patients received thoracic radiation, and 11 received systemic chemotherapy. Follow-up information was available in 16 cases; 12 patients presented with local or metastatic relapse, and 10 patients died of their tumour. The overall 5-year survival was 14.5%.

CONCLUSION

Primary thymic carcinoma is a very heterogeneous group of tumours of the anterior mediastinum with an aggressive clinical behaviour, and a poor overall prognosis.

Apoptosis in right-ventricle biopsy is not predictive of graft survival

Myocardial dysfunction is common in grafted hearts from brain-dead donors, but the mechanisms involved remain unclear, although apoptosis has been suggested to play an important role. In this study, we investigated the presence of apoptotic myocardial cells in donor hearts as compared to control hearts to determine whether pre-existing apoptosis can predict donor heart dysfunction. Apoptosis was studied by in situ DNA fragmentation assay and by Western Blotting for caspase-3, the pivotal executive caspase of the apoptotic pathway. We show that brain-death induced myocardial apoptosis was not predictive of myocardial dysfunction in transplanted hearts.

Mitochondrial permeability transition in cardiomyocyte apoptosis during acute graft rejection

Evidence indicates that acute cardiac graft rejection is associated with cardiomyocyte apoptosis. Mitochondrial permeability transition (MPT) induces apoptotic cell death. We sought to determine whether MPT might play a role in cardiomyocyte apoptosis in the rat model of heterotopic cardiac transplantation. Syngenic and allogenic transplantations were performed, and both native and grafted hearts were harvested 3 or 5 d after transplantation for detection of acute rejection, assessment of Ca(2+)-induced MPT, and myocardial apoptosis by TUNEL staining and caspase 3 activity. Allogenic grafts developed severe acute rejection at day 5 with concomitant cardiomyocyte apoptosis (apoptotic index: 7.1 +/- 1.0% vs. 1.0 +/- 0.2% in syngenic hearts, and caspase 3 activity: 38 +/- 25 vs. 5 +/- 9 nmol/mg, in allogenic vs. syngenic grafts, respectively). At day 5, Ca(2+)-induced MPT was dramatically altered in allogenic when compared with syngenic grafts (mean Ca(2+) overload averaged 0 +/- 20 vs. 280 +/- 30 microM in allogenic and syngenic grafts, respectively). NIM811, a nonimmunosuppressive derivative of cyclosporin A (CsA), that specifically inhibits the MPT pore, did not alter acute rejection, but significantly delayed Ca(2+)-induced MPT pore opening, attenuated caspase 3 activity and cardiomyocyte apoptosis in allogenic grafts. This suggests that mitochondrial permeability transition pore opening may play an important role in cardiomyocyte apoptosis associated with acute cardiac graft rejection.

Primary cardiac Burkitt lymphoma in a child

Primary cardiac lymphoma (PCL) is a rare and usually fatal malignancy, seldom reported in children. This report describes the case of a 10-year-old boy who presented with multiple intracardiac masses which, when biopsied, proved to be small non-cleaved cell (Burkitt's) lymphoma. The first two cycles of chemotherapy according to the LMB 96 protocol were given under close cardiological supervision, with good response. The treatment was then continued with full-dose chemotherapy, without any cardiological complication. The patient who was treated by chemotherapy alone remains in complete remission 36 months after the end of treatment and can presently be considered as cured, without late cardiac effect.

Circumstances of death and gross and microscopic observations in a series of 200 cases of sudden death associated with arrhythmogenic right ventricular cardiomyopathy and/or dysplasia

BACKGROUND

Sudden death is a possible consequence of arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). Prevalence of ARVC/D in unexpected sudden cardiac death (USCD), however, remains imprecise, as do circumstances of death and ARVC/D-associated gross and microscopic findings, especially His bundle anomalies.

METHODS AND RESULTS

We reviewed 14 000 forensic autopsies required by judicial authorities from January 1980 to January 1999 in a 2 000 000-resident area. Age, gender, and circumstances of death were recorded. Hearts were examined macroscopically and microscopically. In this series, the ARVC/D group accounted for 200 consecutive cases (10.4%) of USCD, including 108 males and 92 females (average age 32.5 and 34.5 years, respectively). Nearly one third of deaths occurred during the fourth decade of life. Circumstances of death were various, but 75.6% occurred during everyday life events (at home, 63.1%; in the street, 6.6%; or at work, 6.1%); only 7 cases (3.5%) occurred during sports activity. Nineteen cases (9.5%) happened during the perioperative period. Adipose infiltration of the right ventricle was either isolated (20%) or associated with fibrosis (74.5%) and lymphocytes (5.5%). A total of 14.5% of cases had cardiac hypertrophy, assessed by an increase in heart weight and/or left ventricular wall thickness. In most cases, the His bundle and its branches were abnormal either because of infiltration of adipose tissue (8.1%), fibrosis (54.3%), or both (5.6%).

CONCLUSIONS

In ARVC/D, both sexes are equally affected, and there is a peak of risk during the fourth decade. Death most frequently occurs during sedentary activity. His abnormalities and left ventricular hypertrophy may be associated with ARVC/D.

Clinically and histologically silent Q fever endocarditis accidentally diagnosed by PCR

A case of Q fever endocarditis was diagnosed in a patient with no sign of active endocarditis by performing PCR targeting eubacterial 16S rDNA on the resected mitral valve. The diagnosis was confirmed by detection of high levels of anti-Coxiella burnetti antibodies, positive immunohistologic analysis of the valve tissue with specific antibodies and culture of C. burnetti from the valve tissue. As this patient had an unexplained aggravation of valve dysfunction, we recommended routine serologic testing for C. burnetti to allow the diagnosis of Q fever endocarditis at a very early stage.

[Sudden death during anesthesia: human error, drug related or cardiac death?]

We carried out a retrospective analysis of 1500 forensic autopsies following sudden unexpected cardiac death. This analysis showed a group of 43 cases that could have been related to surgery and/or anaesthesia. Pathological examination revealed the existence of cardiac lesions in 40 cases: arrhythmogenic right ventricular cardiomyopathy (14 cases), coronary artery disease (9 cases), cardiomyopathy (8 cases), structural abnormalities of the His bundle (7 cases), mitral valve prolapse (1 case) and acute myocarditis (1 case). These disorders are compatible with a paroxysmal (rhythmic) phenomenon at the origin of the cardiac arrest. Identification of the cause of death in a patient who was presumed to be at low risk may provide major relief to the patient's family and the medical staff.

[Malignant mesothelioma with osteoblastic heterologous elements]

A 59 year-old man with a history of asbestos exposure presented with a right pleural effusion and a diffuse pleural thickening with focal calcifications on chest X-ray. Cytological examination of pleural fluid indicated malignant mesothelioma. A biopsy specimen showed malignant mesothelioma surrounding a fragment of mature bone. The patient was treated with intrapleural interferon, but relapsed 3 years later. A fresh biopsy specimen showed round tumor cells surrounding osteoid substance. Only ten cases of this rare variant of malignant mesothelioma with osteoblastic heterologous elements have been reported in the literature. The most difficult differential diagnosis is primary pleural osteosarcoma.

[Nonspecific interstitial pneumonitis: a new anatomoclinical entity among idiopathic diffuse interstitial pneumonias]

Nonspecific interstitial pneumonitis with fibrosis has been individualized within the group of idiopathic diffuse interstitial pneumonias by pathological criteria. It is differentiated from usual interstitial pneumonitis by the temporal uniformity of the lesions, a prominent inflammatory interstitial infiltration, and the absence of honeycombing. Clinical and functional symptoms are those of diffuse interstitial pneumonitis. An etiology may be found in about half the cases, including connective tissue disease, exposure to organic antigens, or recent acute lung injury. Computed tomography of the chest shows bilateral ground glass opacities, and alveolar opacities with a peribronchiolar or patchy distribution. Prognosis is rather good, since a majority of patients improve when treated with corticosteroids or with an association of corticosteroids and immunosuppressive drugs. These etiologic and prognostic features justify the individualization of nonspecific interstitial pneumonitis with fibrosis as a distinct clinicopathological entity.

[Anatomy and anatomopathology of benign vocal cord lesions]

After 30 years of experience comprising more than 3000 suspension laryngoscopies, we are putting forward a classification of the main benign lesions of the vocal cords. Among the acquired group, we make a distinction between those caused by vocal overuse and abuse and those with a cause within the vocal cord. Congenital lesions are certainly more common than is usually thought. The hypothesis of a congenital origin would certainly justify a larger prospective study.