Can cell-free DNA (cfDNA) in pleural lavage serve as a predictive and prognostic biomarker among surgically treated Stage I-III a nonsmall cell lung cancer (NSCLC)? A pilot study.

BACKGROUND AND OBJECTIVES: The role of cell-free DNA (cfDNA) in operable nonsmall cell lung cancer (NSCLC) is unclear. This study was aimed to evaluate the feasibility for identification of cfDNA in pleural lavage fluid and its correlation with plasma in resectable NSCLCs. METHODS: Consecutively resected NSCLCs were evaluated for cfDNA levels in preoperative plasma (PLS1), intraoperative pleural-lavage (PLV) and postoperative (at 1 month) plasma sample (PLS2). CfDNA was isolated and measured quantitatively by qPCR in a TaqMan probe-detection approach using the human ß-actin gene as the amplifying target. RESULTS: All (n = 34) except one were negative for malignant cells in PLV cytology. CfDNA could be isolated from all the three samples (PLS1, PLV, and PLS2) successfully in each patient. The median cfDNA levels in PLS1, PLV and PLS2 were 118 ng/mL (IQR 61-158), 167 ng/mL (IQR 59.9-179.9) and 103 ng/mL (IQR 66.5-125.4) respectively. The median follow-up was 34.1 months (IQR 25.2-41.6). A significant overall-survival (OS) and disease-free survival (DFS) were recorded for patients with cfDNA level cut-offs at 125, 170, and 100 ng/mL, respectively for PLS1, PLV, and PLS2. Patients with raised cfDNA in PLS1 (>125 ng/mL) and PLV (>170 ng/mL) had significantly poorer 2-year OS, p = 0.005 and p = 0.012, respectively. The hazards (OS) were also higher for those with raised cfDNA in PLV (HR = 5.779, 95% CI = 1.162-28.745, p = 0.032). PLV (>170 ng/mL) had increased pleural recurrences (p = 0.021) and correlated significantly with poorer DFS at 2-years (p = 0.001) with increased hazards (HR = 9.767, 95% CI = 2.098-45.451, p = 0.004). Multivariable analysis suggested higher cfDNA in PLV as a poor prognostic factor for both OS and DFS. CONCLUSIONS: Among patients with operable NSCLC, it is feasible to identify cfDNA in pleural lavage and correlate PLV cfDNA with pleural recurrences and outcomes.

A study on the morbid histopathological changes in COVID-19 patients with or without comorbidities using minimally invasive tissue sampling.

COVID-19 causes morbid pathological changes in different organs including lungs, kidneys, liver, and so on, especially in those who succumb. Though clinical outcomes in those with comorbidities are known to be different from those without-not much is known about the differences at the histopathological level. To compare the morbid histopathological changes in COVID-19 patients between those who were immunocompromised (Gr 1), had a malignancy (Gr 2), or had cardiometabolic conditions (hypertension, diabetes, or coronary artery disease) (Gr 3), postmortem tissue sampling (minimally invasive tissue sampling [MITS]) was done from the lungs, kidney, heart, and liver using a biopsy gun within 2 hours of death. Routine (hematoxylin and eosin) and special staining (acid fast bacilli, silver methanamine, periodic acid schiff) was done besides immunohistochemistry. A total of 100 patients underwent MITS and data of 92 patients were included (immunocompromised: 27, malignancy: 18, cardiometabolic conditions: 71). In lung histopathology, capillary congestion was more in those with malignancy, while others like diffuse alveolar damage, microthrombi, pneumocyte hyperplasia, and so on, were equally distributed. In liver histopathology, architectural distortion was significantly different in immunocompromised; while steatosis, portal inflammation, Kupffer cell hypertrophy, and confluent necrosis were equally distributed. There was a trend towards higher acute tubular injury in those with cardiometabolic conditions as compared to the other groups. No significant histopathological difference in the heart was discerned. Certain histopathological features were markedly different in different groups (Gr 1, 2, and 3) of COVID-19 patients with fatal outcomes.

Dataset for reporting of thymic epithelial tumours: recommendations from the International Collaboration on Cancer Reporting (ICCR).

AIMS: Thymic epithelial tumours (TET), including thymomas and thymic carcinomas and thymic neuroendocrine neoplasms, are malignant neoplasms that can be associated with morbidity and mortality. Recently, an updated version of the World Health Organization (WHO) Classification of Thoracic Tumours 5th Edition, 2021 has been released, which included various changes to the classification of these neoplasms. In addition, in 2017 the Union for International Cancer Control (UICC) / American Joint Committee on Cancer (AJCC) published the 8th Edition Staging Manual which, for the first time, includes a TNM staging that is applicable to thymomas, thymic carcinomas, and thymic neuroendocrine neoplasms. METHODS AND RESULTS: To standardize reporting of resected TET and thymic neuroendocrine neoplasms the accrediting bodies updated their reporting protocols. The International Collaboration on Cancer Reporting (ICCR), which represents a collaboration between various National Associations of Pathology, updated its 2017 histopathology reporting guide on TET and thymic neuroendocrine neoplasms accordingly. This report will highlight important changes in the reporting of TET and thymic neuroendocrine neoplasms based on the 2021 WHO, emphasize the 2017 TNM staging, and also comment on the rigour and various uncertainties for the pathologist when trying to follow that staging. CONCLUSION: The ICCR dataset provides a comprehensive, standardized template for reporting of resected TET and thymic neuroendocrine neoplasms.

Cytomorphology of paediatric hepatocellular carcinoma: A useful diagnostic adjunct.

INTRODUCTION: Hepatocellular carcinoma (HCC) is a common primary malignancy of the liver but is rare in the paediatric age group; thus, it may be misdiagnosed as the more common tumour, hepatoblastoma. Management varies in both these tumours, and pathological diagnosis thus plays an important role for definitive therapy. Only a few case reports available in the literature have described the cytological characteristics of paediatric HCC. The present study was thus planned to evaluate the cytomorphological features of paediatric HCC. METHODS: Cases diagnosed with HCC on ultrasound-guided fine needle aspiration cytology over a period of 14 years were retrieved. The cases were evaluated for detailed cytological features including cellularity, architecture, sinusoidal wrapping, trabecular thickness, necrosis, anisonucleosis, chromatin, nucleoli, nuclear contours, bi- or multinucleation, intranuclear and intracytoplasmic inclusions, naked nuclei, extra-medullary haematopoiesis, monomorphism, and nuclear overlapping. RESULTS: Twelve cases of HCC were included in the study. The median age at diagnosis was 10 years. Serum alpha-fetoprotein level was raised in most of them. Five of the 12 cases were characterised as moderately differentiated, three as poorly differentiated, two as well differentiated, and two as the fibrolamellar type of HCC. Cytohistological correlation was performed in seven cases. CONCLUSIONS: Ultrasound-guided fine needle aspiration serves as a useful tool to diagnose paediatric HCC and differentiate it from other primary hepatic malignancies, especially hepatoblastoma which closely mimics HCC in this age group, as serum alpha protein levels and imaging findings are unable to distinguish these two tumours.

Can cytology reliably subtype non-small cell lung carcinomas?

Cytology specimens play an important role in the diagnosis and predictive testing of lung cancer. While morphological characterisation of small cell and non-small cell lung carcinomas (NSCLC) on cytology is possible, further subtyping of NSCLC into adenocarcinoma and squamous cell carcinoma morphology is also mandatory in the current era of personalised medicine. Notably, cytology specimens in different forms (fine needle aspiration, exfoliative, and cell block) with or without immunocytochemistry are reliable sources for accurate diagnosis of adenocarcinoma and squamous cell carcinoma as evidenced by numerous studies present in the literature. However, there are instances where subtyping of NSCLC based on morphology alone is challenging on cytology samples, especially non-cell block preparations. In this paper, we will discuss current concepts, advances, and challenges of subtyping NSCLC in cytology specimens.

Differential expression of miRNA in histological subtype of Wilms tumor.

INTRODUCTION: Wilms tumor is the most common renal malignancy in children and difficult to differentiate from other paediatric abdominal tumors radiologically, necessitating an invasive procedure for diagnosis. Previous studies have shown the potential role of miRNA as biomarkers for diagnosis, histological subtyping and prognosis. In this study, we are exploring the role of miRNA in the histological subtyping of Wilms tumor in the Indian population. MATERIALS AND METHODS: A total of 15 cases of Wilms tumor were evaluated for global miRNA expression analysis by microarray. Total RNA was extracted from fresh frozen tumor and miRNA expression analysis was performed using Agilent platform. Unsupervised clustering was done to analyse the data. RESULTS: Using unpaired student T test, top 10 significantly differentially expressed miRNA were selected which could differentiate among different histological subtypes by unsupervised hierarchical clustering and principal component analysis. The presence of necrosis, heterologous differentiation led to change in miRNA expression profile and led to a distinct cluster formation. CONCLUSIONS: A panel of 5 miRNAs (miR1, 133b, 299-3p, 499a-5p, 491-3p) could differentiate among different histological subtypes of Wilms tumor, thus avoiding an invasive procedure in children, however, further confirmation using real time PCR analysis will be needed.

An Open-Label Randomized Controlled Trial Comparing the Efficacy and Safety of Pemetrexed-Carboplatin versus (Weekly) Paclitaxel-Carboplatin as First-Line Chemotherapy in Advanced Non-Squamous Non-Small Cell Lung Cancer.

BACKGROUND: Before the approval of first-line immune checkpoint inhibitors, platinum doublets were the standard of care in patients with treatment-naïve advanced non-small cell lung cancer (NSCLC) without targetable driver mutations. Pemetrexed-platinum combinations are preferred in non-squamous NSCLC. However, there has been no direct comparison to paclitaxel-carboplatin. METHODS: This open-label randomized trial was designed to compare pemetrexed-carboplatin with (weekly) paclitaxel-carboplatin in treatment-naïve advanced/metastatic non-squamous NSCLC without driver mutations. Patients received either pemetrexed 500 mg/m2 and carboplatin AUC 5 every 3 weeks, or paclitaxel 80 mg/m2 on day 1, day 8, and day 15 with carboplatin AUC 5 every 4 weeks for 4 cycles. Patients in both arms were allowed to receive pemetrexed maintenance. RESULTS: A total of 180 patients were enrolled. The study was terminated early; however, at the time of analysis 75.8% of the required events had occurred. Finally, 164 patients were evaluable, 83 in the pemetrexed arm and 81 in the paclitaxel arm. After a median follow-up of 17 months, progression-free survival (PFS) rates at 6 months were not different in the two treatment arms (47.45 vs. 48.64%, p = 0.88). The median PFS values were 5.67 months (95% CI 3.73-7.3) and 5.03 months (95% CI 2.63-7.43) in each arm, respectively (HR 1.13, 95% CI 0.81-1.59, p = 0.44). The median overall survival was also not different: 14.83 months (95% CI 9.5-18.73) and 11.3 (95% CI 8.3-19.7; HR 1.19, 95% CI 0.8-1.78, p = 0.37). All grade toxicities were similar except for alopecia and peripheral neuropathy, which were higher in the paclitaxel arm. CONCLUSION: Pemetrexed-carboplatin is not superior to (weekly) paclitaxel-carboplatin as the first-line regimen in advanced non-squamous NSCLC in terms of PFS.

Recent updates in thoracic SMARCA4-deficient undifferentiated tumor.

Germline inactivating mutations in SMARCA4 (SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4) gene encoding for BRG1 (Brahma related gene-1) are the molecular drivers in small cell carcinoma of ovary, hypercalcemic type (SCCOHT) and in malignant rhabdoid tumors (MRT) that occur in the context of rhabdoid tumor predisposition syndrome-type 2. Somatic SMARCA4 mutations and/or loss of BRG1 have been identified in a variety of adult-onset epithelial and mesenchymal neoplasms. Among thoracic tumors, these include subsets of smoking-related non-small cell lung carcinoma (NSCLC) and a relatively rare, newly recognised tumor entity: thoracic SMARCA4-deficient undifferentiated tumor (SMARCA4-UT). Less than 100 cases of SMARCA4-UT have been reported to date. They present as large compressive and infiltrative mediastinal, lung and/or pleural masses in middle-aged male smokers. They are undifferentiated tumors composed of sheets of small/epithelioid and/or rhabdoid tumor cells variably expressing epithelial markers and consistently showing loss of BRG1 and the closely related protein, Brahma (BRM). Frequent expression of stem cell markers (SOX2, CD34, SALL4) is noted. Despite gene expression profiles similar to MRTs and SCCOHT, they show striking genomic overlap with SMARCA4-mutant NSCLC with frequent TP53, STK11, KEAP1, and KRAS mutations, high tumor mutation burden (TMB), and presence of smoking related molecular signatures in tumor cells. SMARCA4-UT show uniformly poor survival and are irresponsive to conventional therapies. Immunotherapy responses are variable but promising, although PDL1 expression appears to be of poor predictive value. Drugs exploiting genetic and epigenetic mechanisms of SMARCA4 antagonism hold promise for future targeted therapies.

Advances in cytology of lung cancer.

Cytopathology has emerged as a promising platform in precision oncology especially after the revolutionary change in our understanding of the concept of lung cancer etiopathogenesis. With increasing use of minimally invasive techniques for sample acquisition, it becomes almost mandatory to utilize precious cytology samples maximally and judiciously by appropriate triaging of the specimen and timely action of the cytopathology team. Existing patient management protocols require accurate morphologic and molecular diagnosis of the lung cancer specimens which needs knowledge about evolving techniques related to specimen procurement, updates of genomic variants of lung cancer and recently developed molecular testing platforms and algorithms which are capable enough to use even miniscule amount of diagnostic material. This review provides a brief knowledge about advances in cytology of lung cancer which are helpful for developing correct clinical management strategies.

Utility of the Milan system for reporting salivary gland cytopathology during rapid on-site evaluation (ROSE) of salivary gland aspirates.

OBJECTIVE: Rapid on-site evaluation (ROSE) is a fine needle aspiration (FNA) technique for ensuring sampling adequacy and triaging samples. The Milan system for reporting salivary gland cytopathology (MSRSGC) is a standardised reporting system which aims to improve risk stratification. There is scant literature on the diagnostic value and agreement of MSRSGC on ROSE with final cytological diagnosis in salivary gland FNAs. We aimed to assess the concordance of MSRSCG categorisation and diagnosis on ROSE with final cytological and histological diagnosis. METHODS: This prospective study included consecutive salivary gland FNAs for which ROSE was performed over a six-month period. MSRSGC category and diagnosis on ROSE were compared with the final cytological diagnosis and MSRSGC category, and histopathological diagnosis, where available. RESULTS: Sixty salivary gland aspirates were included. The adequacy rate with ROSE was 100%. Using the MSRSGC classification during ROSE, 26 (43.2%) samples were categorised as benign neoplasm, 21 (35%) as malignant neoplasm, 9 (15%) as non-neoplastic, and one each (1.7%) belonged to the remaining four categories. MSRSGC categorisation on ROSE concurred with final the cytological diagnosis in 58/60 cases (96.7%). Discrepancies in MSRSGC categories on ROSE included one atypia of undetermined significance with final report as non-neoplastic, and one non-diagnostic as suspicious for malignancy. Good correlation of MSRSGC categories on ROSE with final histopathological diagnosis (88.9% concordance) was also noted. CONCLUSIONS: MSRSGC on ROSE shows good concordance with final cytology and histopathology diagnosis, indicating that categorisation according to MSRSGC has utility in ensuring that adequate material is obtained and triaged appropriately for the diagnosis of salivary gland aspirates.

Sinonasal IgG4-related disease: a rare and emerging entity broadening the differential diagnosis in the sinonasal universe.

BACKGROUND: IgG4-related disease (IgG4-RD) is a multi-organ immune-mediated disorder characterized by fibroinflammatory mass-forming lesions, mimicking malignancy or infection. While well-documented in salivary glands, orbit and thyroid in the head and neck, sinonasal IgG4-RD is rare. METHODS: Cases of sinonasal IgG4-RD were retrieved, and clinicopathological features reviewed. RESULTS: Seven cases of sinonasal IgG4-RD were identified over a 2-year period, including three males and four females, with an age range of 13-48 years (median: 32 years). Patients presented with cheek swelling, pain and visual disturbances. Serum IgG4 levels were mildly elevated. Storiform fibrosis, obliterative phlebitis and plasma cell infiltration were seen in varying proportions. Destruction of bone and subepithelial mucoserous glands was present. ALK-1 negativity distinguished from inflammatory myofibroblastic tumor. CONCLUSION: Sinonasal IgG4-RD expands the growing spectrum of IgG4-RD. A high degree of suspicion is required to include IgG4-RD in differential diagnosis of sinonasal masses, and perform detailed histological and immunohistochemical workup for accurate diagnosis.

p16 Immunoexpression in sinonasal and nasopharyngeal adenoid cystic carcinomas: a potential pitfall in ruling out HPV-related multiphenotypic sinonasal carcinoma.

AIMS: Adenoid cystic carcinoma (AdCC) is frequent in the sinonasal region. The recently described human papilloma virus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC) histopathologically resembles solid AdCC, but has a better outcome. Thus, clinical and pathogenetic differences between HMSC and sinonasal AdCC necessitate their distinction. We conducted this study to assess p16 immunoexpression in previously diagnosed AdCC cases, and to identify HMSC cases in p16 immunopositive cases. METHODS AND RESULTS: Cases diagnosed as sinonasal and nasopharyngeal AdCC were retrieved. Histomorphological features were reviewed. Immunohistochemistry (IHC) for p16 was performed. HPV testing was performed in p16-positive cases by mRNA in-situ hybridisation (mRNA ISH) and polymerase chain reaction (PCR) assay. MYB rearrangement was assessed by fluorescence in-situ hybridisation. One hundred and two AdCC cases were retrieved. Six cases (5.9%) showed diffuse p16 positivity. HPV mRNA ISH and PCR were negative in p16-positive cases. Two cases showed MYB rearrangement. p16-positive cases were composed of basaloid cells demonstrating a cribriform pattern, at least focally. The predominant pattern was cribriform in three and solid in three cases. One case showed two distinct components: keratinising squamous cell carcinoma and cribriform AdCC. Other morphological patterns seen were tubular, reticular, epithelial-myoepithelial carcinoma-like, and glomeruloid, forming a minor component of the tumour area. CONCLUSIONS: p16 staining alone, even when diffuse and strong, cannot be used as a surrogate for HPV testing to distinguish sinonasal AdCC from HMSC. p16 IHC should be accompanied by more specific methods, such as mRNA ISH, so as not to erroneously diagnose HMSC over sinonasal AdCC, bearing in mind the highly aggressive nature of the latter.

In-vitro evaluation of rice straw biochars' effect on bispyribac-sodium dissipation and microbial activity in soil.

Dissipation of bispyribac-sodium was estimated in an unamended sandy loam soil and soil amended with rice straw and its biochars in pot culture experiment. Effect of herbicide and amendments on abundance and activity of soil microbial parameters was also assessed by determining soil biological parameters. Amendment type, application rate and soil moisture had differential influence on bispyribac-sodium dissipation and soil's microbial parameters. Amendment of soil with rice straw and its biochars enhanced the dissipation of bispyribac-sodium (DT50 = 7.55-18.44 days) as compared to unamended soil (DT50 = 23.13-28.60 days) and dissipation decreased in this order: rice straw >350BC > 550BC > CBC amended soil > unamended soil. Dissipation of bispyribac-sodium decreased with increase in amendment level of rice straw and its biochars in soil. Irrespective of amendment type and application rate, bispyribac sodium was more persistent under submerged conditions than at field capacity and its DT50 was 10.13 to 28.60 and 7.55-27.14 days, respectively. Dehydrogenase, alkaline phosphatase activity and bacterial population indicated that application of the organic amendment decreased negative effects of the herbicide on soil enzymatic activities. These findings prove that biostimulation using rice straw and its biochars has the potential to decrease the persistence of bispyribac-sodium and minimize its environmental hazards.

EWSR1 translocation in primary hyalinising clear cell carcinoma of the thymus.

AIMS: In thymic carcinomas, focal clear cell change is a frequent finding. In addition to a prominent, diffuse clear cell morphology, some of these carcinomas show an exuberant hyalinised extracellular matrix, and therefore probably represent a separate entity. However, a characteristic genomic alteration remains elusive. We hypothesised that, analogous to hyalinising clear cell carcinomas of the salivary gland, hyalinising clear cell carcinomas of the thymus might also harbour EWSR1 translocations. METHODS AND RESULTS: We identified nine archived cases of thymic carcinoma with focal clear cell features and two cases that showed remarkable hyalinised stroma and prominent, diffuse clear cell morphology. These two cases expressed p40 and were negative for Pax8, CD5, and CD117. Programmed death-ligand 1 was highly positive in one case (70%), and negative in the other one. EWSR1 translocation was identified in both cases of hyalinising clear cell carcinoma, and was absent in all nine carcinomas that showed clear cell features without substantial hyalinisation. In one of the EWSR1-translocated cases, a fusion between exon 13 and exon 6 of EWSR1 and ATF1, respectively was identified by next-generation sequencing. CONCLUSIONS: These findings suggest that the EWSR1 translocation and possibly the EWSR1-ATF1 fusion might be unifying genomic alterations for thymic clear cell carcinomas with prominent hyalinised stroma, for which we propose the term 'hyalinising clear cell carcinoma of the thymus'. Because the immunophenotype is unspecific, testing for the EWSR1 translocation might be helpful in discriminating this entity from other thymic neoplasms or metastases, in particular those with clear cell change.

Interobserver and intraobserver variation in the morphological evaluation of noninvasive follicular thyroid neoplasm with papillary-like nuclear features in Asian practice.

To evaluate the current diagnostic criteria in reporting nuclear features of noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), nine Asian pathologists with expertise in thyroid reviewed virtual slides of 30 noninvasive follicular patterned thyroid lesions according to the nuclear scoring system originally proposed by an international expert and a more detailed scoring system proposed by the Asian Working Group. The interobserver agreement for nuclear grading score was generally moderate (kappa value = 0.452). The best consistency fell on the chromatin features (kappa value = 0.658-1.000). A fair to moderate interobserver agreement was demonstrated in the evaluation of nuclear elongation, nuclear overlapping, membrane irregularities and distribution of papillary thyroid carcinoma (PTC) type nuclear features. A slight agreement was rendered for the evaluation of the nuclear enlargement. Intraobserver agreement was substantial to perfect when comparing results of both scoring systems. However, both scoring systems were not able to reliably separate NIFTP from an encapsulated follicular variant PTC with minimal lymph node metastasis or BRAFV600E mutation. Although the three-point nuclear scoring system for the diagnosis of NIFTP is widely used in Asian practice, interobserver variation was considerable. Ancillary immunohistochemical or molecular testing might be helpful in differentiating NIFTP from true PTC.

Comparison of laboratory-developed test & validated assay of programmed death ligand-1 immunohistochemistry in non-small-cell lung carcinoma.

Background & objectives: Inhibitors of immune checkpoint regulators, programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1), improve outcome in advanced non-small-cell lung carcinoma (NSCLC). Tumours expressing PD-L1 protein are more likely to benefit from this targeted therapy. Multiple concurrent clinical trials evaluating different anti-PD-1/PD-L1 therapies have validated five different immunohistochemistry (IHC) assays using varied antibody clones and staining conditions. This study was aimed at identification of a single harmonized PD-L1 assay for tumour tissue conservation and cost-effectiveness in patients with NSCLC. Methods: The performance of low-cost, manual, laboratory-developed technique (LDT) PD-L1 IHC assay using the easily available SP142 clone was compared with trial validated Ventana SP263 IHC performed on automated Ventana staining platform on tumour sections of NSCLCs. Results: Eighty cases of NSCLC were included. SP263 and SP142 stained both tumour cells and immune cells. The concordance rate of tumour cell staining was about 76 per cent, with SP263 detecting more tumour cells in 16 per cent of cases. The concordance rate of immune cell staining was only 61 per cent, with SP142 detecting more immune cells in 24 per cent of cases. The sensitivity, specificity, positive and negative predictive values of manual SP142 LDT assay against gold standard SP263 Ventana assay were 70, 94, 86 and 86 per cent, respectively, at positivity thresholds of ≥1 per cent tumour cell staining. Interpretation & conclusions: The study findings suggested that LDT using SP142 clone showed only moderate concordance with SP263 Ventana assay, and the two assays were not interchangeable. More such validation studies need to be done to generate information that can complement patient therapy in cases of NSCLC.

Histotyping of Indian thymomas: A clinicopathologic study from north India.

Background & objectives: Thymomas are rare, but most common anterior mediastinal lesions. The histomorphologic spectrum of thymic epithelial tumours (TETs) in Indian population has not been explored in depth. This study was aimed to assess the histomorphology of TETs in the Indian patients and correlate clinical parameters with pathological features. Methods: It was a retrospective study conducted in a tertiary referral hospital in north India. All morphologically confirmed cases of TETs since 2009 were included. Clinical details and histology slides were reviewed using the Modified Masaoka-Koga staging system and WHO 2015 classification. Clinicopathological correlation and survival analysis were done. A comparative review from other published Indian studies was performed. Results: A total of 219 cases of TETs (138 resections and 81 biopsies) were identified. The most common histomorphologic type was B2, and the most frequent stage was I. Types A/AB were common in older age (P<0.01). Clinically, higher stage tumours were found mostly in men (P<0.01), and these were Type B thymomas (P<0.01). Myasthenia gravis was more common in women (P<0.02) and in lower stages (P<0.05). Survival analysis revealed significant association between recurrence and tumour stage. Although thymic carcinoma was diagnosed on biopsy, no resectable case was identified. Interpretation & conclusions: Our findings showed that the thymomas in Indian patients were most commonly Stage I tumours of B2 and AB histotypes. Resected thymic carcinomas were conspicuously absent in our study. More studies need to be done to establish the frequency and biology of TETs from India.

Endobronchial ultrasound-guided transbronchial needle aspiration cytology in patients with known or suspected extra-pulmonary malignancies: A cytopathology-based study.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the primary modality for mediastinal lymph node staging in lung carcinoma. We aimed to evaluate its utility in extra-pulmonary malignancies (EPM). METHODS: Database search of EBUS-TBNA aspirations (2013-2017) done in patients with known/suspected EPMs and mediastinal lymphadenopathy/masses was performed. All archived cytology/histology material was reviewed and categorised as positive, negative and unsatisfactory. RESULTS: The selected 139 patients included 100 patients with known EPMs, 11 patients with known lymphoma, and 28 patients with suspected EPM of unknown primary. EBUS-TBNA was adequate in 110 patients (79%), including 21 patients who yielded only reactive lymphoid tissue. Satisfactory blood clot cores were obtained in 34 patients and contributed significantly to diagnosis and ancillary testing. Metastasis was detected in 45 patients with known EPM, predominantly originating from a known primary in the breast in females (56%) and squamous cell carcinomas of head and neck in males (60%). Granulomatous lymphadenopathy was identified in 16 patients with known EPM (16%). Lymphoma relapse and granulomatous lymphadenopathy were identified in three and four patients with known lymphoma, respectively. In patients with suspected EPM of unknown primary site, malignancy was confirmed in 21 patients, predominantly representing metastatic adenocarcinomas (n = 5) and neuroendocrine neoplasms (n = 5). Immunocytochemistry was performed in 16 of these cases and aided in characterisation of primary site/type of tumour in 12 cases. CONCLUSION: EBUS-TBNA is efficient for screening mediastinal lymph nodes/masses for malignancy in EPMs. Procuring sufficient material for ancillary testing would improve diagnostic accuracy and reduce need for resampling.

Spectrum of cytomorphological features of extranodal NK/T-cell lymphoma, nasal type.

OBJECTIVE: Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is an aggressive extranodal lymphoma of NK-cell or T-cell lineage. Its clinical features overlap with those of several sinonasal mass lesions. While the histopathological features are well described, diagnosis is often difficult, owing to presence of extensive coagulative necrosis, so that repeated biopsies may sometimes be necessary for correct diagnosis. Literature on cytological findings of ENKTL is limited. METHODS: Cytomorphological features of cases of histologically confirmed ENKTL having corresponding cytology samples were reviewed retrospectively, to identify distinctive features that could possibly suggest this entity. RESULTS: Aspirates from five patients were studied: four from cervical nodes, one from cheek swelling and one from pleural fluid. Two aspirates were reported as positive for malignancy, two as atypical lymphoid proliferation and one was non-diagnostic. Pleural fluid was reported as malignant, favouring a diagnosis of carcinoma. On cytology, aspirates showed medium to large cells with folded, indented nuclei and abundant pale cytoplasm, some with tongue-like cytoplasmic protrusions. A distinctive feature was presence of large loose clusters of tumour cells with arborising capillaries running through them. Interestingly, necrosis was consistently absent. Subsequent biopsies from palate (three cases) and nasal masses (two cases) confirmed the diagnosis of ENKTL. CONCLUSIONS: Suspicion of ENKTL on cytology is crucial for timely diagnosis to avoid diagnostic delay, especially when only highly necrotic biopsy samples are available. Awareness of distinctive cytomorphological features is required to make fine needle aspiration an effective diagnostic tool for initial diagnosis and for evaluation of possible recurrences.

Cytological diagnosis of Langerhans cell histiocytosis: A series of 47 cases.

OBJECTIVE: Langerhans cell histiocytosis (LCH) is a rare disease affecting predominantly children and young adults but can be found in any age group. Diagnosis of LCH is often difficult and can be delayed because of its rarity. The present study highlights the cytomorphological features in a large cohort of cases. An accurate cytological diagnosis may avoid unnecessary biopsy and guide appropriate management. METHOD: Fourty seven (47) cases of LCH diagnosed on cytological material & fine-needle aspiration (FNA) over a period of 14 years (2003-2016) were retrieved from the archives. The cytological smears were evaluated and microscopic findings collected by semi-quantitative assessment done by two different pathologists RESULT: The age at the diagnosis of the patients ranged from 9 months to 28 years. The majority of cases were in the age group of 0-5 years. The most common site was head and neck region, which included cervical lymphadenopathy and scalp swelling. Two cases were diagnosed each from inguinal lymph node and bronchio-alveolar lavage (BAL). Cytological smears in the majority of the cases were moderate to highly cellular (58%) and showing abundant Langerhans cell in (72%) of cases. Areas of necrosis were seen in 38%, while 78% of cases showed giant cells. The majority of cases showed mild eosinophilia (61%), sparse lymphocytosis (83%) and mild neutrophilic infiltration (64%). There were 1-2 mitoses per 10 high power field in 12 cases (25.5%). No abnormal mitoses were identified. CONCLUSION: The presence of cells with features of Langerhans cells associated with the expression of selected immunohistochemical markers allow the diagnosis of LCH on cytological samples, sparing more invasive procedure as a biopsy.