Pathologic diagnosis of malignant mesothelioma: chronological prospect and advent of recommendations and guidelines

Malignant mesothelioma is rare and difficult to diagnose. Its identification depends upon pathological investigation (cyto-histological assessment and immunohistochemistry) supported by clinical and radiological evidence. In the last decade, the standardization of diagnostic methods has become a major focus of debate among pathologists and clinicians. This has led to the writing of guidelines and recommendation for the diagnosis to achieve the goal of a standard diagnosis. In this article, a chronological view relating to the pathological diagnosis of MM is presented together with a review of guidelines/recommendation

Pathologic diagnosis of malignant mesothelioma: chronological prospect and advent of recommendations

Malignant mesothelioma (MM) is rare and difficult to diagnose. Its identification dependsupon pathological investigation (cyto-histological assessment and immunohistochemistry)supported by clinical and radiological evidence. In the last decade, thestandardization of diagnostic methods has become a major focus of debate among pathologistsand clinicians. This has led to the writing of guidelines and recommendationfor the diagnosis to achieve the goal of a standard diagnosis. In this article, a chronologicalview relating to the pathological diagnosis of MM is presented together with a reviewof guidelines and recommendations.

Probiotics Reduce Inflammation in Antiretroviral Treated, HIV-Infected Individuals: Results of the "Probio-HIV" Clinical Trial

BACKGROUND: HIV infection results in damage to the gastrointestinal (GI) tract, microbial translocation and immune activation. These are not completely normalized with combined antiretroviral therapy (cART). Moreover, increate morbidity and mortality of cART-treated HIV-infected individuals is associated with inflammation. METHODS: In order to enhance GI tract immunity, we recruited and treated 20 HIV-infected humans with cART supplemented with probiotics and followed inflammation and immunological parameters (clinical trial number NCT02164344). 11 HIV seronegative subjects were included as control group. The enumeration of CD4+, CD8+, CD38+ and HLA-DR+ lymphocytes were evaluated on peripheral blood; HIV-RNA levels, sCD14, d-dimer, C-reactive protein (CRP) high sensitivity C-reactive protein (hsCRP), IL-6 and Lipopolysaccharide Binding Protein (LBP) were assayed on plasma. RESULTS: We observe that cART does not normalize the levels of immune activation in HIV positive patients anyway inflammation and markers of microbial translocation were significantly reduced with probiotic supplementation. Patients show a clear and statistically significant reduction in the levels of immune activation on CD4 T-lymphocytes, for both markers CD38 and HLA-DR and their simultaneous expression, LBP and hsCRP plasma levels after probiotic diet supplementation settling to values comparable to controls. CONCLUSIONS: Supplementing cART with probiotics in HIV-infected individuals may improve GI tract immunity and there by mitigate inflammatory sequelae, ultimately improving prognosis

Lung on fire. A very severe case of fire-eater's lung

A 19-year-old male smoker presented in the emergency room after accidental aspiration of an unquantifiable amount of Pyrofluid, a liquid mixture of high-boiling aliphatic/paraffin aromatic free hydrocarbons, during a fire-eating performance. A few minutes after the aspiration he started to feel sick, with shortness of breath and mild dry cough. On admission to our hospital, he had an episode of emesis and presented burning retrosternal chest pain and dyspnoea. Physical examination revealed oxygen saturation (SpO2) on ambient air of 92%, tachypnoea, tachycardia, normal temperature. Chest auscultation showed the presence of breath sounds without additional pathological sounds. The rest of the systemic examination was normal. Oropharyngoscopy was negative for oral lesions. Laboratory exams showed a neutrophilic leukocytosis (white cell count (WCC) 15.56×109/L, neutrophil 10.91×109/L), without increased C reactive protein (CRP) levels. Arterial blood gases on room air revealed PaO2 8.9 kPa, PaCO2 5.5 kPa, pH 7.30, (HCO3 -) 20 mmol/L, (Lac) 3.8 mmol/L, and PaO2/inspired oxygen fraction (FiO2) 42.4 kPa. Chest X-ray demonstrated mild accentuation of the broncho-vascular structure with a consolidation in the left basal area (figure 1A). High-resolution chest CT (HRCT) showed bilateral parenchymal consolidation involving most of the inferior lobes and a complete occlusion of the lower lobar bronchus bilaterally; moreover, fluid-dense effusion was present in the right basal area (figure 1B). Although blood cultures and microbiological tests on sputum were negative, a broad-spectrum antibiotic therapy was initiated with piperacillin/tazobactam. The patient was also treated with systemic steroids, analgesics and oxygen therapy via a Venturi mask at FiO2 of 0.4

Thyroglobulin measurement in the washout of fine needle aspirates for the diagnosis of suspicious cervical lymph nodes

Ultrasound-guided fine-needle aspiration cytology (FNAC) for suspicious cervical lymph nodes (CLN) is the gold standard technique for the identification of metastases from differentiated thyroid carcinomas. Thyroglobulin protein (Tgp) assay in the washout of needles employed for FNA biopsies (FNAB) has been reported to refine and support FNAC performances, especially in cases of inadequate sampling or cystic lymph nodes. In the present work, we evaluated the usefulness of routine measurement of Tgp in the FNAB washout of suspicious cervical lymph nodes (CLN), and its ability to increase the FNAC accuracy in the diagnosis of metastatic CLN. A case study of 45 CLN with histological diagnosis from 36 patients was analyzed. Histology showed metastases from papillary thyroid carcinomas (PTC) in 31 CLN, from anaplastic thyroid cancer (ATC) in 3 CLN, from medullary thyroid cancer (MTC) in 4 CLN, and metastases from extrathyroidal malignancies in 5 CLN. Two CLN analyzed were found to be non-neoplastic. The overall accuracy of FNAC was 82.9%, and that of Tgp was 91.1%, not statistically different. However, Tgp determination was found essential in 4 cases of metastatic CLN from DTC with inadequate cytology, and in 1 case in which the FNAC provided a false negative result. We demonstrated that FNAC and Tgp assay show similar diagnostic accuracies, and that Tgp measurement may represent the only available information in case of inadequate lymph node sampling or cystic lymph nodes

Biosafety in surgical pathology in the era of SARS-Cov2 pandemia. A statement of the Italian Society of Surgical Pathology and Cytology

Surgical pathology units face chemical and biological risks. While chemical risks have been intensely evaluated since the formalin ban, less attention has been drown to biological risks. The actual epidemiologic situation due to the SARS-CoV-2 pandemia has raised a series of questions, which need to be addressed as soon as possible. We have to pursue two lines of action: on one hand we must immediately adopt urgent measures to reduce the risk of SARS-CoV-2 infection of laboratory personnel, and on the other hand, we must address crucial technical and organizational aspects of biological risk reduction, preserving as much as possible the quality of tissue and cell samples. The evaluation of biological risk is an analytical process which involves different steps: a) characterization of the hazard (also known as risk assessment) and b) definition of a risk reduction strategy (also known as risk mitigation) 1. Risk assessment implies a) the identification of the intrinsic biologic characteristics of the infectious agent, and b) the identification of the laboratory procedures related to the agent. The intrinsic biologic characteristics of infectious agents are classified in 4 risk groups (RG) by the laboratory biosafety manual of the WHO 2. The RG range from level 1 (RG1) which includes microorganisms that are unlikely to cause human or animal disease, to level 4 (RG4) which includes pathogens which cause serious diseases, that can be readily transmitted from one individual to another, and for which effective treatment and preventive measures are not usually available. Risk mitigation includes the definition of the appropriate a) level of biosafety of the laboratory, b) type of personal protection equipment (PPE), c) type of infrastructure and equipment, and d) education of involved personnel. Laboratory biosafety is graded in 4 levels (BSL-1 to BSL-4) as exhaustively described in the laboratory biosafety manual of the WHO 2, and these levels are usually also defined by law (in Italy by the D. Lgs. 81/2008). BSL are a series of protections, which include individual safeguards designed to protect laboratory personnel, as well as the surrounding environment and community. The biosafety level required in laboratories derives from the characterization of the risk, and is not automatically derived from the risk group to which the pathogenic agent belongs. It is obvious that the biosafety level for a laboratory which cultivates a RG3 agent, will be higher than the level needed for a laboratory which performs diagnostic tests on inactivated biomaterials on the same agent. Specific checklists, derived from the WHO laboratory biosafety manual, which in Italy are also defined by the National Institute of Labor Safety Insurance (Istituto Nazionale Assicurazione Infortuni sul Lavoro) in its 6th Fascicle published in 2010 3 are necessary to verify the compliance of a given laboratory with the required biosafety level

Merkel cell carcinoma: a population-based study on mortality and the association with other cancers

Few population-based epidemiological data are available on Merkel cell carcinoma (MCC), a rare lethal non-melanoma skin cancer. We analysed multiple-cause-of-death records to describe MCC mortality and trends and the association with other primary cancers. We reviewed all 6,713,059 death certificates in Italy (1995-2006) to identify those mentioning MCC. We evaluated the association with other primary cancers by calculating the ratio of observed to expected deaths, using a standardized mortality ratio (SMR)-like analysis. We also evaluated the geographic distribution of deaths. We identified 351 death certificates with the mention of MCC. The age-adjusted mortality was 0.031/100,000, with a significant trend of increase and a slight north-south gradient. There was a significant deficit for solid cancers (SMR = 0.15) and a non-significant excess for lymphohematopoietic malignancies (SMR = 1.62). There were significant excesses for chronic lymphocytic leukemia (SMR = 4.07) and Waldenstrom's macroglobulinemia (SMR = 27.2) and a non-significant excess for chronic myeloid leukemia (SMR = 5.12). The increase in MCC mortality reflects the incidence trend in the literature. The association with chronic lymphocytic leukemia confirms the importance of immunologic factors in MCC. Regarding Waldenstrom's macroglobulinemia, an association with MCC has never been reported

Thyroid Imaging Reporting and Data System Score Combined with the New Italian Classification for Thyroid Cytology Improves the Clinical Management of Indeterminate Nodules

The new Italian cytological classification (2014) of thyroid nodules replaced the TIR3 category of the old classification (2007) with two subclasses, TIR3A and TIR3B, with the aim of reducing the rate of surgery for benign diseases. Moreover, thyroid imaging reporting and data system (TI-RADS) score appears to ameliorate the stratification of the malignancy risk. We evaluated whether the new Italian classification has improved diagnostic accuracy and whether its association with TI-RADS score could improve malignancy prediction. We retrospectively analyzed 70 nodules from 70 patients classified as TIR3 according to the old Italian classification who underwent surgery for histological diagnosis. Of these, 51 were available for cytological revision according to the new Italian cytological classification. Risk of malignancy was determined for TIR3A and TIR3B, TI-RADS score, and their combination. A different rate of malignancy (p=0.0286) between TIR3A (13.04%) and TIR3B (44.44%) was observed. Also TI-RADS score is significantly (p=0.003) associated with malignancy. By combining cytology and TI-RADS score, patients could be divided into three groups with low (8.3%), intermediate (21.4%), and high (80%) risk of malignancy. In conclusion, the new Italian cytological classification has an improved diagnostic accuracy. Interestingly, the combination of cytology and TI-RADS score offers a better stratification of the malignancy risk

Authors' response: Mezei et al's "Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis"

: Mezei et al's letter (1) is an opportunity to provide more details about our study on pericardial and tunica vaginalis testis (TVT) mesothelioma (2), which is based on the Italian national mesothelioma registry (ReNaM): a surveillance system on mesothelioma, with individual asbestos exposure assessment. Incidence of pericardial mesothelioma has been estimated around 0.5 and 0.2 cases per 10 million person-years in men and women, respectively, and around 1 case for TVT mesothelioma. ReNaM collected 138 cases thanks to its long period of observation (1993-2015) and national coverage. Conducting a population-based case-control study with incidence-density sampling of controls across Italy and over a 23 year time-span should have been planned in 1993 and would have been beyond feasibility and ReNaM scope. We rather exploited two existing series of controls (3). The resulting incomplete time- and spatial matching of cases and controls is a limitation of our study and has been acknowledged in our article. The analysis of case-control studies can nevertheless be accomplished in logistic models accounting for the variables of interest, in both individually and frequency matched studies (4). Furthermore, analyses restricted to (i) regions with enrolled controls, (ii) cases with definite diagnosis, (iii) incidence period 2000-2015, and (iv) subjects born before 1950 have been provided in the manuscript, confirming the strength of the association with asbestos exposure (supplemental material tables S4-7). Following Mezei et al's suggestion, we performed further sensitivity analyses by restriction to regions with controls and fitting conditional regression models using risk-sets made of combinations of age and year of birth categories (5-year classes for both). We confirmed positive associations with occupational exposure to asbestos of pericardial mesothelioma, with odds ratios (OR) (adjusted for region) of 9.16 among women [95% confidence interval (CI) 0.56-150] and 5.63 (95% CI 1.02-31.0) among men; for TVT mesothelioma the OR was 7.70 (95% CI 2.89-20.5). Using risk sets of age categories and introducing year of birth (5-year categories) as a covariate (dummy variables) the OR were similar: OR (adjusted for region) of 9.17 among women (95% CI 0.56-150) and 5.76 (95% CI 1.07-31.0) among men; for TVT the OR was 9.86 (95% CI 3.46-28.1). Possible bias from incomplete geographical overlap between cases and controls has been addressed in the paper (table S4) and above. In spatially restricted analyses, OR were larger than in those including cases from the whole country, indicating that bias was towards the null. Mezei et al further noted that "the regional distribution of controls is different from that of person-time observed". This objection is not relevant because the above analyses were adjusted by region. Our controls were provided by a population-based study on pleural mesothelioma (called MISEM) and a hospital-based study on cholangiocarcinoma (called CARA). In MISEM, the response rate was 48.4%, a low but not unexpected rate as participation among population controls is usually lower and has been declining over time (5). It is important to underline that ReNaM applied the same questionnaire that was used for interviews and carried out the same exposure assessment as both MISEM and CARA. As repeatedly stated in ReNaM papers (6-7), each regional operating center assesses asbestos exposure based on the individual questionnaire, other available information, and knowledge of local industries. Occupational exposure to asbestos is classified as definite, probable or possible. Occupational exposure is (i) definite when the subject`s work was reported or otherwise known to have involved the use of asbestos or asbestos-containing materials (MCA); (ii) probable when subjects worked in factories where asbestos or MCA were used, but their personal exposure could not be documented; and (iii) possible when they were employed in industrial activities known to entail the use of asbestos or MCA. Hence, the definite and probable categories are closer to one another and were combined in our analyses. In any case, restricting analyses to subjects with definite occupational exposure and using each set of controls separately, as suggested by Mezei et al, yielded elevated OR for TVT and pericardial mesothelioma among men using both the above described modelling strategies; the OR could not be calculated for women. There were 70 (25 pericardial and 45 TVT) occupationally exposed mesothelioma cases. In population-based studies, analyses by occupation are limited by the low prevalence of most specific jobs. As briefly reported in our paper, for purely descriptive purposes, the industrial activity of exposure (cases may have multiple exposures), were construction (22 exposures, 7 and 15 for pericardial and TVT mesotheliomas, respectively), steel mills and other metal working industries (4 and 11), textile industries (2 and 3), and agriculture (2 and 5); other sectors had lower exposure frequencies. The absence of industries like asbestos-cement production, shipbuilding and railway carriages production/repair should not be surprising and had already been observed (7). In the Italian multicenter cohort study of asbestos workers (8), given the person-years of observation accrued by workers employed in these industries and gender- and site-specific crude incidence rates, approximately 0.1 case of pericardial and 0.2 of TVT mesothelioma would have been expected from 1970 to 2010. Even increasing ten-fold such figures to account for higher occupational risks among these workers would not change much. Asbestos exposure in agriculture has been repeatedly discussed in ReNaM reports (9: pages 70, 73, 128, 164 and 205). Exposure opportunities included the presence of asbestos in wine production, reuse of hessian bags previously containing asbestos, or construction and maintenance of rural buildings. Similarly, mesothelioma cases and agricultural workers exposed to asbestos have been noted in France (10). In conclusion, the additional analyses we performed according to Mezei et al's suggestions confirm the association between asbestos exposure and pericardial and TVT mesothelioma, supporting the causal role of asbestos for all mesotheliomas. ReNaM`s continuing surveillance system with national coverage is a precious platform for launching analytical studies on pleural and extra pleural mesothelioma. References 1. Mezei G, Chang ET, Mowat FS, Moolgavkar SH. Comments on a recent case-control study of malignant mesothelioma of the pericardium and the tunica vaginalis testis Scand J Work Environ Health. 2021;47(1):85-86. https://doi.org/10.5271/3909 2. Marinaccio A, Consonni D, Mensi C, Mirabelli D, Migliore E, Magnani C et al.; ReNaM Working Group. Association between asbestos exposure and pericardial and tunica vaginalis testis malignant mesothelioma: a case-control study and epidemiological remarks. Scand J Work Environ Health. 2020;46(6):609-617. https://doi.org/10.5271/sjweh.3895. 3. Greenland S. Control-initiated case-control studies. Int J Epidemiol 1985 Mar;14(1):130-4. https://doi.org/10.1093/ije/14.1.130. 4. Pearce N. Analysis of matched case-control studies. BMJ 2016 Feb;352:i969. https://doi.org/10.1136/bmj.i969. 5. Bigert C, Gustavsson P, Straif K, Pesch B, Brüning T, Kendzia B et al. Lung cancer risk among cooks when accounting for tobacco smoking: a pooled analysis of case-control studies from Europe, Canada, New Zealand, and China. J Occup Environ Med 2015 Feb;57(2):202-9. https://doi.org/10.1097/JOM.0000000000000337. 6. Marinaccio A, Binazzi A, Marzio DD, Scarselli A, Verardo M, Mirabelli D et al.; ReNaM Working Group. Pleural malignant mesothelioma epidemic: incidence, modalities of asbestos exposure and occupations involved from the Italian National Register. Int J Cancer 2012 May;130(9):2146-54. https://doi.org/10.1002/ijc.26229. 7. Marinaccio A, Binazzi A, Di Marzio D, Scarselli A, Verardo M, Mirabelli D et al. Incidence of extrapleural malignant mesothelioma and asbestos exposure, from the Italian national register. Occup Environ Med 2010 Nov;67(11):760-5. https://doi.org/10.1136/oem.2009.051466. 8. Ferrante D, Chellini E, Merler E, Pavone V, Silvestri S, Miligi L et al.; the working group. Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure. Occup Environ Med 2017 Dec;74(12):887-98. https://doi.org/10.1136/oemed-2016-104100. 9. ReNaM VI Report. Available from: https://www.inail.it/cs/internet/docs/alg-pubbl-registro-nazionale-mesoteliomi-6-rapporto.pdf. Italian 10. Marant Micallef C, Shield KD, Vignat J, Baldi I, Charbotel B, Fervers B et al. Cancers in France in 2015 attributable to occupational exposures. Int J Hyg Environ Health 2019 Jan;222(1):22-9. https://doi.org/10.1016/j.ijheh.2018.07.015