The Difficulties and Ease of Diagnosing Anaplastic Large Cell Lymphomas on Cytology.

Introduction and Objectives: Anaplastic large cell lymphoma (ALCL), a unique non-Hodgkin lymphoma (NHL), is a CD30-positive neoplasm of T-cell lineage. Its distinctive yet variable cytomorphology makes diagnosing fine needle aspiration cytology (FNAC) challenging. This study was undertaken to study the cytomorphology and the utility of immunocytochemical (ICC) stains on cytology in ALCL and to discuss their morphological differential diagnosis. Materials and Methods: The present study was conducted in the Department of Pathology of a tertiary care center. A retrospective review was done from January 2017 to July 2022, and all histopathologically and immunohistochemically (IHC) diagnosed cases of ALCL were taken and correlated with the cytological diagnosis. Results: Twenty-one cases of histopathology examination and IHC-proven cases of ALCL were retrieved from the departmental archives and reviewed. The ages ranged from 3 to 80 years (median age 28 years). Commonly noted cytomorphologic features included singly dispersed large pleomorphic cells, hallmark cells, and Reed-Sternberg-like cells. CD15, CD30, epithelial membrane antigen, and anaplastic lymphoma kinase-1 were some of the ICC stains used in this study. All 21 cases had cytology correlation. Fourteen cases had concordant cyto-histological correlation. Seven cases of histopathologically proven ALCL were reported as Hodgkin lymphoma (HL) in three, ALCL/anaplastic diffuse large B-cell lymphoma, HL/ALCL, poorly differentiated carcinoma, and NHL in one case each on cytology. Conclusion: ALCL has a reasonably distinct cytomorphologic appearance and ICC staining pattern, and a careful interpretation of both helps arrive at a reliable FNAC diagnosis.

A comparison between conventional and the Paris systems of reporting urinary cytopathology with a literature update.

INTRODUCTION: Owing to certain inherent limitations of earlier reporting systems, "The Paris System for Reporting Urinary Cytology (TPS)" was implemented in 2015 to standardize reporting urine cytology with more stringent cytomorphologic criteria. We share our post-TPS experience, comparing it with the conventional system (CS). AIM: To assess and compare the cyto-histopathologic/cystoscopic agreement between the conventional and the Paris systems (CS and TPS) for reporting urine cytology. MATERIALS AND METHODS: It is a cross-sectional study involving urine samples from 170 patients divided into two groups (CS and TPS). Of the 170 cases, 85 were reported according to the CS, and 85 were reported according to TPS with all the relevant clinical, radiologic, and cystoscopic findings. Using the kappa statistics, both groups were statistically analyzed for sensitivity, specificity, predictive values, and agreement. RESULTS: The sensitivity and specificity for high-grade urothelial carcinoma (HGUC) as per TPS were 83.33% and 94.59%, respectively, while they were 73.47% and 80.56% for the conventional system. The agreement for HGUC with TPS was 87.06% with a kappa value of 0.7416, while it was 76.5% with a kappa value of 0.53 for the CS. Implementing the TPS minimized usage of the atypical urothelial cells (AUC) category, increasing the clarity in detecting HGUC. CONCLUSION: TPS provides better agreement with histopathology than the CS for diagnosing HGUC, which is attributable to stringent TPS criteria that prompt cytopathologists to look more diligently for morphologic and numeric criteria.

The urgency of Burkitt lymphoma diagnosis in fluid cytology-A tertiary care experience.

BACKGROUND: Burkitt lymphoma (BL) is an aggressive high-grade B-cell non-Hodgkin lymphoma commonly diagnosed in young age and is known to involve extra nodal sites. But the involvement of body fluids by BL is an uncommon presentation. Rapid diagnosis of BL is vital to prevent complications like tumour lysis syndrome. Cytological examination of body fluids continues to be an indispensable tool for rapid diagnosis of BL. OBJECTIVES: In this study, we aim to study the clinical, cytomorphological and immunophenotypic characteristics of BL involving serous effusions and other fluids. MATERIALS AND METHODS: In this retrospective study, 17 cases reported as BL in fluid cytology from 2016 to 2022 were collected and reviewed. We performed a comprehensive analysis of the clinical data, cytomorphological features, immunophenotyping data along with the haematological workup of these cases. We have also compared with the histopathological diagnosis for those cases where biopsy was available. RESULTS: BL more commonly involved ascitic fluid (52%), followed by pleural fluid (4 cases) and cerebrospinal fluid (CSF; 4 cases). Primary diagnosis of BL in fluid was done in 88% of the cases. Bone marrow involvement was noted in two cases. Cytological smears showed discrete monomorphous population of medium-sized atypical lymphoid cells with frequent apoptotic bodies. Classic cytoplasmic punched out vacuoles were observed in 88% of the cases. Immunophenotyping data was available for 12 cases in which tumour cells showed positivity for CD20 (100%), CD10 (4 of 7 cases), BCL6 (3 of 5 cases) and cMYC (7 of 7 cases-100%) and were negative for Terminal deoxynucleotidyl transferase (TdT) (11 of 11 cases). Mean Ki67 labelling index was 95%. Histopathological diagnosis was available for 9 cases, and there was 100% agreement between cytological and histopathological diagnosis in 7 cases. CONCLUSION: Precise diagnosis of BL can be rendered in body fluids by identification of classic cytomorphological features and by performing supportive ancillary tests in fluids for immunophenotyping.

Utility of the Growth Differentiation Factor-15 in the Differential Diagnosis of Follicular-Patterned Lesions of the Thyroid on Cytopathologic and Histopathologic Samples.

Background Follicular-patterned lesions are a major gray zone in thyroid cytopathology. The recently introduced 2022 World Health Organization (WHO) classification emphasizes the importance of genetic alterations in thyroid neoplasms with the introduction of certain newer terminologies that are expected to cause remarkable changes in cytopathologic and histopathologic reporting. Although molecular assays such as the Afirma gene expression classifier and the ThyroSeq are already in use, there has been an ongoing search for further reliable molecular markers. The growth differentiation factor-15 (GDF-15) is one among them. This study aimed to determine the diagnostic utility of GDF-15 mRNA expression in frozen tissue and fine-needle aspiration (FNA) samples from follicular-patterned thyroid lesions and neoplasms. Methodology The real-time quantitative polymerase chain reaction was performed on 75 frozen tissue and FNA samples each from 19 cases of follicular thyroid hyperplasia (FTH), 10 nodular goiters (NGs), 17 follicular thyroid adenomas (FTAs), eight follicular thyroid carcinomas (FTCs), 12 follicular variant of papillary thyroid carcinomas (FVPTCs), and nine classic papillary thyroid carcinomas (CPTCs) that were diagnosed according to the 2017 WHO classification of thyroid neoplasms. The GDF-15 mRNA expression in all these cases was assessed and compared with the control thyroid tissue samples. One-way analysis of variance and the Kruskal-Wallis test were performed using GraphPad Prism 8 software to determine the significance of differences in the GDF-15 mRNA levels among various thyroid lesions. Results A higher GDF-15 mRNA expression was noted in the malignant thyroid neoplasms including FTC, FVPTC, and CPTC in comparison to FTA, with a fold change between the malignant and benign groups being more than 244.18 times. A difference in the fold change was noted between FTH and FTA with an increase in GDF-15 mRNA level in the latter, which was statistically not significant. Conclusions The fact that GDF-15 mRNA was studied both on fine-needle aspiration cytologic and the frozen tissue material and that the majority of the lesions studied were follicular-patterned establishes the GDF-15 as a potential marker not only for diagnosing malignant thyroid neoplasms of the follicular epithelium but also in distinguishing benign and malignant follicular-patterned neoplasms of the thyroid.

Bacillary Positive Tuberculous Body Fluid Smears: A Perspective on How Fast to Use Acid Fast.

Background Tuberculous effusions are common. Classically, they are described as bacteria poor and lymphocyte rich. Our experience, however, has been more varied. We compiled this rare group of bacteria-positive tuberculous fluids to document their cytologic spectrum and to look for possible predictors of bacillary positivity. Methods Fifty-one cases of bacillary positive fluids were identified and their clinicopathological details were noted. Per case, the smear background was assigned as either clear, caseous, suppurative, granular proteinaceous or frankly hemorrhagic. Fine, punched-out vacuoles in the smear background were also noted. The bacillary load in each case was classified from scanty to 3+. Eventually, the clinicopathologic variables were tabulated for frequency and studied for any association with bacillary presence. Results Only 19 of the 51 patients had a history of tuberculosis. Retropositive patients comprised a small proportion (9.8%) and did not always indicate strong (3+) bacillary positivity. The granular proteinaceous background was the most frequent (35%) pattern. Only a suppurative background was associated with strong bacillary positivity. Fine vacuoles were seen almost always with caseous and granular proteinaceous backgrounds but without statistical significance. Conclusion Tuberculous effusions can have diverse smear backgrounds, not necessarily one rich in caseous material. When tuberculosis is known or clinically suspected, non-classical findings such as abundant neutrophils or suppurative background should not dissuade one from requisitioning mycobacterial stains. In fact, acid-fast stains should probably routinely accompany Giemsa slides of clinically idiopathic effusions in endemic areas since it is still the cheapest and fastest method for a conclusive diagnosis.

Disseminated rhinosporidiosis masquerading as soft tissue round cell tumour diagnosed by fine needle aspiration cytology.

Rhinosporidium seeberi belongs to the eukaryotic class Mesomycetozoea and causes chronic granulomatous lesions known as rhinosporidiosis. Rhinosporidiosis frequently involves the nasal cavity and nasopharynx through transepithelial invasion. Atypical presentations of this disease at other body sites have been reported, including the subcutis, visceral organs, bones, and genitals. Only a few cases of cutaneous and subcutaneous involvement have been reported to date. This chronic granulomatous condition is known for its recurrence following autoinoculation unless the correct diagnosis and appropriate treatment are given. We describe a case of an immunocompetent adult who had undergone fine needle aspiration cytology (FNAC) of mass-like swellings in the right thigh and right calf at another healthcare centre and had been diagnosed with a small round blue cell tumour. FNAC at our centre confirmed a rare case of rhinosporidiosis that was clinically mimicking a soft tissue neoplasm of the lower extremity, and the erroneous interpretation of the prior cytology studies had resulted in misinterpretation of the individually dispersed pathogenic organisms as individual malignant cells. FNAC of rhinosporidiosis can lead to early diagnosis and prompt treatment of this pathogen when it presents at unanticipated body sites.

CSF Involvement by Nonhematolymphoid Malignancies: A Descriptive Study with Emphasis on Cytomorphological Clues.

Introduction: Detection of malignant cells in cerebrospinal fluid (CSF) samples in suspected cases of malignancy is critical for the management of patients. CSF involvement by nonhaematolymphoid malignancies is less common. We aimed to study the cytomorphologic characteristics of various nonhaematolymphoid malignancies in CSF. Methods: A retrospective cytomorphological analysis of 27 CSF cytology smears reported as positive or suspicious for nonhematolymphoid malignancies from January 2010 to April 2020 over 10 years was carried out. Smears in all cases were prepared by cytospin technique and stained with May-Grunwald-Giemsa (MGG) and papanicolaou (Pap) staining procedures. Cell immunohistochemistry/immunocytochemistry was done wherever cell block/extra slides were available. Results: Twenty-four of 27 cases were interpreted as "positive," while three were reported as "suspicious" of malignancy. Nineteen of 27 cases were metastatic adenocarcinomas including three suspicious malignancy cases with the primary sites of origin being the breast (10), stomach (2), rectum (1), gall bladder (1), lung (1), and four cases of unknown primary. Of the remaining positive cases, there were five cases of metastatic medulloblastoma, two cases of metastatic pineoblastomas, and one case of metastatic extraskeletal Ewings sarcoma. Each of these metastatic malignancies had at least a single diagnostic cytomorphological clue, similar to those observed in other body cavities and primary malignancy sites. Conclusion: Nonhematolymphoid malignancies are readily diagnosable on CSF cytology, most of them are metastatic. Identification of malignant cells in CSF is critical, as it has therapeutic and prognostic implications.

Preliminary Cytomorphologic Diagnosis of Hematolymphoid Malignancies in Effusions: A Cyto-histo Correlation with Lessons on Restraint.

Background: Effusions as part of hematologic neoplasms are rare and as a primary presentation, rarer. In standalone laboratories of developing countries, resorting to techniques such as flow cytometry or immunohisto/cytochemistry may not be possible. A near definitive diagnosis on cytomorphology would, therefore, be an ideal beginning. To that end, we compiled our cases of primary hematolymphoid effusions, devising reproducible reporting categories and looked at their concordance with the final histopathology. Subjects and Methods: Fifty-four cases of primary hematolymphoid effusions over 10 years with cytology-histopathology correlation were chosen. Post morphology assessment, the cases were organized into six categories: suspicious of hematolymphoid malignancy, non-Hodgkin lymphoma-high-grade (NHL-HG), low-grade NHL (NHL-LG), Burkitt lymphoma, acute leukemias, and plasma cell dyscrasias. Discordance with histology was assigned as major and minor based mainly on therapeutic implications. Results: Concordance was seen in a good number (81.5%) of cases. The NHL-HG and NHL-LG categories contributed to 33.3% each of major discordance. Tuberculosis and epithelial malignancies comprised the bulk of the major discordance. Overdiagnosis of a high-grade lymphoma for a histologically proven low-grade follicular lymphoma was the only case with minor discordance. Conclusion: The cytologic categories used are not foolproof for hematologic neoplasms but have a fairly good concordance. A scanty abnormal population should always be viewed with suspicion and definitive labels should be avoided. While morphologic examination is fraught with danger, a good assessment directs the judicious selection of ancillary methods, and hence cannot be supplanted.

Cytology of primary nocardiosis of the lymph node: A rare report.

Primary nocardiosis of the lymph node is a rare presentation even in an immunocompromised individual, with few case reports in the literature. In addition, Nocardia farcinica as observed in our case, is rarely documented, making it an interesting report. This paper clearly illustrates the subtle morphological clues that can be used to diagnose nocardial infection.

The strength of cytomorphology and efficacy of immuno-cytochemistry in distinguishing hepatocellular carcinoma from its mimics on fine-needle aspiration cytology.

BACKGROUND: Cytomorphologic distinction of hepatocellular carcinoma (HCC) from its mimics on fine-needle aspiration cytology (FNAC) is often problematic. The present study evaluates the strength of cytomorphology and the utility of an immuno-panel of arginase-1, glypican-3, HepPar-1, thyroid transcription factor (TTF-1) and CK-19 in resolving this diagnostic issue. METHODS: FNAC features of 71 nodular hepatic lesions were studied with an immunocyto/ histochemical (ICC/IHC) panel of arginase-1, glypican-3, HepPar-1, TTF-1 taking 10% positivity as "cut-off." Cytomorpholologic diagnoses were compared with diagnoses made on combined cytomorphologic and ICC/IHC approach. RESULTS: Of 71 cases, 32, 10 and 29 had histopathologic, cell block and clinico-radiologic correlation respectively with 55 metastatic adenocarcinomas (MAC), 13 HCCs and one case each of hepatic adenoma (HA), cirrhotic nodule (CN) and intrahepatic cholangiocarcinoma (CC). Cytoplasmic positivity of HepPar-1 and glypican-3 were noted in 11/13 and 8/13 HCCs respectively; while only 3/13 and 1/13 HCCs revealed cytoplasmic positivity for arginase-1 and TTF-1 respectively. Benign hepatic lesions were negative for glypican-3 and TTF-1, but expressed both arginase-1and HepPar-1. Twenty-one of 55 MACs and the lone case of CC were positive for CK-19; however, all MACs and CC cases were negative for HepPar-1, arginase-1, glypican-3 and TTF-1. The immune-panel had sensitivity, specificity and diagnostic accuracy of 100%, 88.9% and 90.6%, respectively, for differentiating HCC from its morphologic mimics. CONCLUSION: Though a meticulous cytologic evaluation in conjunction with clinicoradiologic profile helps in distinguishing HCC from its benign and malignant mimics; an immunopanel of arginase-1, glypican-3, HepPar-1, TTF-1 and CK-19 drastically improves the diagnostic accuracy.

Malignant phyllodes tumor with liposarcomatous differentiation: Diagnosed on cytology.

Phyllodes tumor (PT) accounts for less than 1% of all primary tumors of the breast and 2% to 3% of all fibroepithelial lesions. We report a case of heterologous liposarcomatous elements in a malignant PT of the breast on Fine needle aspiration cytology (FNAC) and later confirmed by histopathological examination. A 58-years-old woman presented with a huge breast mass for which FNAC was done. Cytology showed features of malignant PT with a good representation of heterologous liposarcomatous areas. The cytological findings were in concordance with the histologic features. Malignant PT and its various heterologous elements of stroma can be diagnosed on FNA cytology when performed optimally. They can be vital for the preoperative assessment of patients suspected with malignancy to formulate the surgical plan accordingly.

Comparison of the quality of the microwave cell-block method with the conventional cell-block method in processing body fluid samples.

INTRODUCTION: Conventional cell blocks (CCB) prepared from cytological specimens are very useful but the method is relatively time-consuming. Suitable modifications in cell-block techniques are beneficial for improving the turnaround time. We share our experience of a rapid microwave cell-block (MCB) technique. AIM AND OBJECTIVES: To study the quality of routine and immunohistochemical (IHC) staining of cell-block sections from serous body fluids prepared by the MCB technique compared with the CCB technique. METHOD: A total of 177 serous body fluid samples were processed by routine centrifugation technique, and the sediments were used for cell-block preparations by both conventional and rapid microwave methods. Cell-block sections were stained with haematoxylin and eosin stain. Haematoxylin and eosin staining quality was analysed using three parameters (cellularity, morphology and staining intensity). IHC for epithelial membrane antigen and calretinin were also performed, and the quality of staining was evaluated on 62/177 samples. Results were analysed using appropriate statistical tests. RESULTS: The time taken for processing cell blocks by the MCB method was 1 hour and 18 minutes compared to 13 hours and 45 minutes by CCB. The quality of sections by both methods showed good agreement for cellularity and intensity of staining, and moderate agreement for morphology. A 100% concordance was noted for distinguishing benign and malignant samples on morphology as well as with IHC stain results. CONCLUSION: Although the techniques are comparable in terms of quality of routine and IHC staining, we recommend using the MCB technique due to its short turnaround time.

Embryonal rhabdomyosarcoma of breast, pleura, and retroperitoneum diagnosed from pleural fluid cytology.

Embryonal rhabdomyosarcoma (ERMS) is a malignant small blue round cell tumor which is commonly seen in head and neck region. Breast and pleural involvement are uncommon. Rhabdomyosarcoma has been rarely reported in the body fluids like ascitic, pleural, and cerebrospinal fluid. In this article, we report an interesting case of ERMS which had deceptive small blue round cells in pleural fluid. The cytomorphological features along with a panel of immunocytochemical markers helped in arriving at the definite diagnosis. Later, biopsy from the breast lump and retroperitoneal mass also revealed the same tumor. This case is reported since it is rare to find sarcoma cells in pleural fluid and highlight the diagnostic difficulties faced during interpretation.

The utility of fine needle aspiration cytology in orbital haematolymphoid neoplasms.

BACKGROUND: Orbital hematolymphoid lesions are rare and usually encountered in elderly patients. Orbital lesions are not easy to biopsy: hence fine needle aspiration cytology (FNAC) can be a very good diagnostic modality for these lesions. MATERIALS AND METHODS: Cases of orbital masses subjected to FNAC dating from 2013 to 2020 were retrieved from our archives. A total of 16 cases with biopsy confirmation were included. All clinical details, the type of procedure, details of the immunocytochemistry (ICC) performed on smear, follow-up biopsy, and their haematological work-up were analysed in detail. RESULTS: Sixteen biopsy-confirmed cases had been diagnosed as orbital haematolymphoid lesions on cytomorphology and further categorised with ancillary studies including ICC. In twelve instances, the cytology impression was congruent with the histopathological diagnosis and eight of the sixteen cases (50%) proved to be primary orbital lymphoma. Four were secondary orbital lymphomas and the remaining four included one case each of plasmacytoma, myeloid sarcoma, Rosai-Dorfman disease and angiolymphoid hyperplasia with eosinophilia. CONCLUSION: FNAC is a minimally invasive procedure for diagnosing most of the haematolymphoid orbital lesions and it has a rapid turnaround time. The accuracy of cytomorphology combined with ICC on smears/cell blocks can be as good as a biopsy for exact categorisation. Additionally, aspirate smears are preferred samples for cytogenetics compared to formalin-fixed tissue blocks, as molecular cytogenetics techniques are frequently employed for diagnostic, prognostic, and therapeutic purposes.