The evolving role of molecular pathology in the diagnosis of salivary gland tumours with potential pitfalls.

Salivary gland tumors are diagnostically challenging owing to the morphological diversity within any tumor type and overlapping histomorphology and immunohistochemistry amongst different tumours. In past two decades, rapid progress has been made in the field of understanding the pathogenesis of these tumours with the discovery of many tumour specific translocations and rearrangements. This includes CRTC1-MAML2 and CRTC-MAML2 in mucoepidermoid carcinoma, MYBNFIB and MYBL1-NFIB fusions in adenoid cystic carcinoma, PLAG1 and HMGA2 in pleomorphic adenoma, ETV6-NTRK3 in secretory carcinoma, NR4A3 rearrangements in acinic cell carcinoma, PRKD1 mutations in polymorphous adenocarcinoma and EWSR1-ATF1 in clear cell carcinoma. This review is a lens for progress made till date in the molecular pathology of salivary gland tumours with a special focus on their role as diagnostic tools and implications on clinical management of the patient as prognostic and predictive markers.

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.

Sinonasal amelanotic melanoma with neuroendocrine differentiation: a diagnostic conundrum.

Mucosal malignant melanoma of the head and neck (HN) is a rare and aggressive neoplasm which constitutes only 1% of all melanomas. Neuroendocrine differentiation is an extremely unusual phenomenon in mucosal melanomas, of which five cases have been reported. We report a rare case of a 63-year-old female who developed sinonasal amelanotic melanoma with immunohistochemical expression of neuroendocrine markers, presenting a diagnostic dilemma. Ultrastructural evidence of melanosomes and neurosecretory granules aided in arriving at the diagnosis. Aberrant immunoexpression of neuroendocrine markers, particularly in an amelanotic melanoma, has critical diagnostic implications, as various malignancies with undifferentiated histomorphology occur at this site, many of which stain positively with neuroendocrine markers. We discuss the differential diagnoses and recommend a high index of suspicion so as not to miss the diagnosis of mucosal melanoma at this location.

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.

Role of Ancillary Techniques in Reporting Serous Fluid Cytology - "Redefining Categories, Refining Diagnosis".

Background: The "International System of Reporting Serous Fluid Cytology (TIS)" together with cytomorphology promotes the use of ancillary techniques to resolve difficulties in reporting serous fluid cytology. Objective: To classify serous effusion fluid samples received at our department in line with "TIS", indicating the risk of malignancy (ROM), and directing appropriate usage of ancillary testing. Materials and Methods: Prospective study carried out from October 2021 to September 2022. The study included all pleural, ascitic, and pericardial fluid samples, reported according to 'TIS'. Flow cytometry and immunocytochemistry were ancillary methods utilized to assist in reporting. Cases with available history and convincing correlations didn't require further assessment. Results: A total of 1200 serous effusion samples were evaluated including 604 pleural, 591 ascitic, and 5 pericardial fluid samples. After categorization, there were 23 samples in non-diagnostic (ND, 1.9%), 575 in negative for malignancy (NFM, 47.91%), 44 in atypia of undetermined significance (AUS, 3.66%), 64 in suspicious for malignancy (SFM, 5.33%), and 494 in malignant category (MAL, 41.16%). Ancillary studies were beneficial in the recategorization of 26% (11/44) AUS cases, 29.6% (19/64) SFM cases, and it helped refine tumor characteristics in 35.42% (175/494) cases categorized as malignant. Final ROM calculated for each category: ND 25%, NFM 18.6%, AUS 66.6%, SFM 88%, and MAL 100%. Conclusion: Serous fluid is an easily obtainable sample that can provide opportunities for ancillary testing with clinical implications. In AUS and suspicious category although, diagnostic yield is increased however, a larger number of cases are required to obtain definite results.

Role of Pap Smear Cervical Cytology in the Diagnosis of Extrauterine Malignancies: Largest Study of 104 Cases from Tertiary Care Cancer Centre in India.

INTRODUCTION: Extrauterine malignancies in cervical samples are rarely seen. It is important to differentiate these cells from those of primary uterine malignancies to determine appropriate line of further investigations and management. Literature on these lesions is limited largely restricted to case reports. The aim of the present study was to study the spectrum and cytomorphological features of extrauterine malignancies in cervical Pap smears. MATERIALS AND METHODS: It is a retrospective and descriptive study conducted in Department of Cytopathology from January 2019 to July 2023. All cases of extrauterine malignancies with available cytology material were included in this study. All cases of primary uterine malignancies, i.e., uterine corpus or cervix confirmed by clinical, radiological, and histopathological examination were excluded. RESULTS: 104 out of 11,674 cytology Pap smears were those of extrauterine malignancy. Diagnosis of extrauterine malignancy was given in 47.1% cases, 30.9% were reported as positive for malignancy without giving the possibility of an extrauterine origin, and 22.0% were reported as atypical glandular cells only. In 56 cases where Pap smear was the first investigation which led to the diagnosis. Most common extrauterine malignancy was adenocarcinoma principally from ovarian, colorectal, and vaginal origin. Other epithelial malignancies noted were urothelial carcinoma and invasive breast carcinoma. Among non-epithelial malignancies, we reported vaginal mucosal melanoma, cutaneous melanoma, acute leukaemia, and anaplastic large cell lymphoma. CONCLUSION: High index of suspicion, presence of squamous and glandular elements with no atypical features, and occasional clusters of cells with marked atypia and usually no necrosis in the background are helpful cytomorphological clues to raise suspicion for extrauterine malignancy. Correlation with serology, radiology, and immunocytochemistry can help in reaching final diagnosis.

Molecular detection of dengue and chikungunya viruses in surveillance of wild-caught Aedes mosquitoes in Punjab, North India.

BACKGROUND: Dengue (DENV), Zika (ZIKV) and chikungunya (CHIKV) viruses are transmitted mainly by Aedes mosquitoes and are responsible for a significant global healthcare burden. The current study aimed to detect arboviruses in the Aedes mosquitoes in close proximity of patients during the transmission season. METHODS: Both immature and adult mosquitoes were collected from in and around the patients' houses. Mosquito pools were homogenized and extracted RNA was subjected to reverse transcription polymerase chain reaction for arboviral detection. Transovarian transmission (TOT) was assessed by screening F0 adults. Mosquito positivity was correlated with the aetiological agents identified in patients. RESULTS: Of 46 pools, 19 consisted of wild Aedes, with arboviral positivity in 53% (10/19) of pools. Among wild A. aegypti pools, positivity of DENV mono-infection, CHIKV mono-infection and DENV+CHIKV co-infection was noted in four, two and three pools, respectively. One wild pool of Aedes albopictus was positive for DENV-1. Similarly, A. aegypti F0 (adult Aedes developed from immatures) pools showed 59.2% (16/27) positivity for arboviruses. F0 Aedes showed positivity in three, six and seven pools for DENV-2, CHIKV and DENV+CHIKV, respectively, suggestive of TOT. DENV serotypes and CHIKV from 24 patients' serum samples were matched with strains isolated from Aedes and correlation was observed in four instances. CONCLUSIONS: The study detected DENV and CHIKV from wild-caught Aedes and found evidence of DENV and CHIKV TOT in F0 adults.

Transthoracic Fine-Needle Aspiration Cytology of Pulmonary Spindle and Mesenchymal Neoplasms: A Pandora's Box.

INTRODUCTION: Pulmonary spindle cell and mesenchymal lesions are paradox for pathologists due to their rarity, overlapping morphology, and differentials ranging from benign to malignant lesions, and correct diagnosis is essential due to major treatment implications. This study highlights the role of fine-needle aspiration cytology, clot core biopsy, and immunohistochemistry in diagnosis of spindle cell lesions in lung, thus playing a key role in patient management. METHODS: It is a retrospective study of lung FNA with predominantly spindle and mesenchymal cells from 2015-2020 which were classified cytomorphologically into spindle, epithelioid, small round cell, and biphasic, and IHC panels are applied accordingly. FNA from mediastinum and chest wall was excluded. RESULTS: 60 cases of lung FNA with spindle and mesenchymal cells were identified and included 6 benign and 54 malignancies which included 24 primary pulmonary malignancies and 30 metastases. Most common primary malignancy was sarcomatoid carcinoma, and most common metastasis was malignant peripheral nerve sheath tumour. FNA was paucicellular in 7 cases and was reported as benign in 7 cases and malignant in 46 cases. There were two false-negative cases. One case of pulmonary blastoma was reported as inflammatory pseudotumour on cytology, and other case of chondrosarcoma was reported as chondroid tumour. Sensitivity and specificity of FNA in distinguishing benign lesions and malignancies were 93.8% and 100%, respectively. CONCLUSION: FNA along with clot core biopsy/cell block and IHC plays a pivotal role in the subsequent pathway taken for diagnostic or therapeutic management of these patients without the need for second sampling or trucut biopsies in a low resource setting.

Clinico-Pathological Spectrum of Alveolar Soft Part Sarcoma: Case Series from a Tertiary Care Cancer Referral Centre in India with a Focus on Unusual Clinical and Histological Features.

OBJECTIVE: Alveolar soft part sarcoma (ASPS) is characterized by distinctive histomorphology of variably discohesive epithelioid cells arranged in nests and translocation of t(x;17) (p11.2;q25) resulting in ASPSCR1-TFE3 fusion. The aim of the present study is to review the clinical, histopathological, and immunohistochemical profile of ASPS with a focus on unusual histological features. MATERIAL AND METHOD: The present study is retrospective and descriptive. All cases with a diagnosis of ASPS were retrieved with clinical and radiology details. RESULTS: 22 patients of ASPS were identified. The most common site was the lower extremity and the size range was 3-22 cm. 54.5% of the patients had metastasis, with the lung as the most common site. Metastasis preceded detection of primary tumour in two cases. All cases showed similar histopathology of monomorphic epithelioid cells arranged in nests encircled by sinusoidal vasculature. Architecturally, the organoid pattern (81.8%) was followed by the alveolar pattern. 68.2% of the cases showed apple bite nuclei as the predominant nuclear feature. Rare nuclear features included binucleation (n=13), multinucleation (n=8), pleomorphism (n=4), nuclear grooves in three cases and intranuclear inclusion in one case, mitosis (n=5), and focal necrosis (n=6). All cases were positive for TFE3 and negative for AE1/AE3, EMA, HMB45, PAX8, MyoD1, SMA, synaptophysin, and chromogranin. Only two cases showed focal S100 positivity while one showed focal desmin positivity. CONCLUSION: Diffuse strong nuclear TFE3 positivity is sensitive for ASPS in an appropriate clinicoradiological context. Due to the high propensity for early metastasis, complete metastatic work-up and long term follow up is recommended.

Utility of CDC DENV1-4 real time PCR assay and trioplex assay for the diagnosis of dengue in patients with acute febrile illness.

Nucleic acid amplification tests (NAATs) have revolutionized reliable detection of dengue virus (DENV) during acute phase of infection. The study evaluated performance of CDC DENV-1-4 real-time assay, trioplex RT-PCR and heminested conventional RT-PCR assay in the diagnosis of DENV. The three NAATs were performed on 107 consecutive samples collected from patients suspected of DENV infection during acute phase of illness. Their performance was compared against composite reference standard, consisting of DENV NS1 antigen ELISA and DENV IgM ELISA. 88/107 study samples were positive by DENV ELISA, either NS1Ag (80), IgM (3) or both (5). The overall sensitivity of CDC DENV-1-4 RT-PCR assay, trioplex RT-PCR assay and conventional multiplex RT-PCR was 68.18%, 54.55% and 38.64%, respectively in diagnosing dengue during acute phase, with an area under the curve of 0.841, 0.773 and 0.693 respectively when compared against composite reference standard. The sensitivity was 82.93%, 73.17% and 51.22%, respectively within three days of illness and 60%, 42.86% and 28.57%, respectively between 4 and 5th day of illness. All the three molecular assays had 100% specificity. Maximum concordance values of 86.9% were recorded among CDC DENV-1-4 rRT-PCR assay and trioplex assay with kappa value of 0.74, suggestive of substantial agreement. CDC DENV-1-4 rRT-PCR assay can be used as a reliable and accurate test for diagnosis of DENV during acute phase of illness.

Comparison between Restorative Materials for Pulpotomised Deciduous Molars: A Randomized Clinical Study.

AIM: To evaluate and compare the clinical outcomes of Cention-N (CN) and stainless steel crowns (SSCs) as restorations for pulpotomised primary molars, and to study clinical and radiographic outcomes of pulpotomies restored with these materials. METHODS: The study was conducted on 60 pulpotomised molars with occlusoproximal caries. These were randomly divided into two groups and restored with either stainless steel crowns or Cention-N. Clinical performance of restorations and clinical and radiographic success of pulpotomy was examined at 6, 9 and 12 months. RESULTS: The mean scores for marginal integrity deteriorated significantly at 6, 9 and 12 months in both groups but in comparison were insignificant. The mean for proximal contact deteriorated significantly for the Cention-N group, whereas the mean for gingival health deteriorated remarkably for the stainless steel crown group at successive evaluations. No tooth in either group showed secondary caries or discomfort on biting, except for one tooth in Cention-N group which presented with secondary caries. The clinical success rate for pulpotomised molars was 100% for both groups until nine months, although this had reduced by the end of 12 months. Radiographically, the success rate was 79.3% for Cention-N, while it was 86.6% for stainless steel crowns at 12 months. There was no significant difference in clinical and radiographic success between either group. CONCLUSION: Cention-N and stainless steel crowns are comparable for marginal integrity. However, crowns maintain significantly better proximal contacts while Cention-N was notably better for gingival health of the restored tooth. Both materials do not show secondary caries and discomfort on biting and are comparable in clinical and radiographic success of pulpotomy at the end of one year.

Outbreak investigation of acute febrile illness from the Himalayan foothills: Solving the puzzle of fever.

In September 2022, Panchkula Civil Hospital reported an outbreak of acute febrile illness (AFI) in Pinjore, located in the Himalayan foothills, Haryana, North India. There was an upsurge of fever cases. Blood samples were taken from suspected patients (n = 58) with AFI and subjected to serology of dengue, chikungunya, Japanese encephalitis, leptospira and scrub typhus. The samples were also screened for West Nile & Zika virus RNA using real-time PCR. Viral strains were characterized by sequencing. Of the 58 cases of AFI, Dengue could be identified in 45 (77.58%) followed by JE and Chikungunya in 2 cases each (3.44%), respectively. Among Dengue positive cases, 44 had monoinfection (97.77%) and 1 patient had dengue and JE. None were positive for Zika, West Nile, Scrub typhus, and Leptospira with the testing protocol. Four patients developed dengue with warning signs, such as abdominal pain in one patient and recurrent vomiting in the remaining three. The dengue serotype could be determined in 17 samples and revealed serotype 2. Molecular evolution analysis based on the complete envelope gene revealed that all DENV-2 strains (n = 13) circulated in the outbreak area belonged to the DENV-2 cosmopoliton genotype. In the early stages of infection, relying only on clinical manifestations is ineffective, so both molecular and serological assays along with clinical diagnosis are noteworthy for determining the aetiology of AFI.

Feature Generalization for Breast Cancer Detection in Histopathological Images.

Recent period has witnessed benchmarked performance of transfer learning using deep architectures in computer-aided diagnosis (CAD) of breast cancer. In this perspective, the pre-trained neural network needs to be fine-tuned with relevant data to extract useful features from the dataset. However, in addition to the computational overhead, it suffers the curse of overfitting in case of feature extraction from smaller datasets. Handcrafted feature extraction techniques as well as feature extraction using pre-trained deep networks come into rescue in aforementioned situation and have proved to be much more efficient and lightweight compared to deep architecture-based transfer learning techniques. This research has identified the competence of classifying breast cancer images using feature engineering and representation learning over the established and contemporary notion of using transfer learning techniques. Moreover, it has revealed superior feature learning capacity with feature fusion in contrast to the conventional belief of understanding unknown feature patterns better with representation learning alone. Experiments have been conducted on two different and popular breast cancer image datasets, namely, KIMIA Path960 and BreakHis datasets. A comparison of image-level accuracy is performed on these datasets using the above-mentioned feature extraction techniques. Image level accuracy of 97.81% is achieved for KIMIA Path960 dataset using individual features extracted with handcrafted (color histogram) technique. Fusion of uniform Local Binary Pattern (uLBP) and color histogram features has resulted in 99.17% of highest accuracy for the same dataset. Experimentation with BreakHis dataset has resulted in highest classification accuracy of 88.41% with color histogram features for images with 200X magnification factor. Finally, the results are contrasted to that of state-of-the-art and superior performances are observed on many occasions with the proposed fusion-based techniques. In case of BreakHis dataset, the highest accuracies 87.60% (with least standard deviation) and 85.77% are recorded for 200X and 400X magnification factors, respectively, and the results for the aforesaid magnification factors of images have exceeded the state-of-the-art.

Mucinous cystadenocarcinoma of the breast: a new entity with broad differentials-a case report.

BACKGROUND: Mucinous cystadenocarcinoma is a rare and recently described primary breast cancer with strikingly similar histomorphology to ovarian, pancreatic, and gastrointestinal counterparts. The diagnosis cannot be made until the metastatic lesion is ruled out. CASE PRESENTATION: We are reporting the case of a 65-year-old woman with primary mucinous cystadenocarcinoma of the breast while exploring clinicopathological features and approach to diagnosis. Though the immunohistochemistry panel of CK7, CK20, CDX2, SATB2, PAX8, mammoglobin, and GATA3 plays a crucial role in ruling out metastasis but aberrant CK20 positivity was seen in our case, the final diagnosis was made after a complete radiological workup. We also noted strong membranous HER2-protein expression and HER2-gene amplification by fluorescence in situ hybridization while in literature this tumor is reported to show mainly triple-negative basal type immunophenotype. CONCLUSION: A combined clinic-radio-immunohistochemical approach is essential to make a diagnosis of primary mucinous cystadenocarcinoma.

Soft tissue aneurysmal bone cyst of left hemithorax: An extremely rare case.

Aneurysmal bone cyst (ABC) is a benign expansile cystic lesion that can affect any bone of the skeleton, especially the femur, tibia, and humerus. Lesions with histologic features of an ABC can be originated within soft tissue in exceedingly rare cases. Extra-skeletal ABC may mimic a variety of benign and malignant lesions and can be confused with other common or rare giant cell-rich tumors of soft tissue. Clinical, radiological and histologic correlation are crucial in reaching the correct diagnosis. Here we report a case of an extra-skeletal ABC arising in left hemithorax in a 13-year-old girl and discuss the common differential diagnosis of this rare entity.

Changes in Voice After Septoplasty: A Pilot Study.

The aim of this study was to evaluate changes in voice after septoplasty in adults using the Dr.Speech assessment module in conjunction with subjective evaluation using Voice Handicap Index (VHI). A total of 50 consecutive patients with symptomatic Deviated Nasal Septum (DNS) undergoing septoplasty were included in the study. Patients fit for surgery underwent septoplasty by standard technique. Voice assessment was done by subjective voice evaluation and Acoustic voice analysis preoperatively, 1 week after surgery and 1 month after surgery. Mean values of both males and females for Fundamental frequency (F0) were within the normal range at all the three times of assessment. No- significant differences were obtained at all the three times of assessment in males and females respectively. Significant results were obtained while comparing the preoperative and postoperative SNR dB values. Mean VHI score at preoperative, 1 week postoperative and 1 month postoperative was 23.2, 22 and 21.5 respectively. No statistical difference was obtained while comparing the mean VHI score at different time intervals. The scores between 0 and 30 are in the mild category, i.e. minimal amount of handicap. The scores of all the patients were less than 30 at all times of assessment. To conclude, post-operative changes in the voice parameters were minimal and not significant, they were indicative of greater acoustical quality of voice and lesser nasalized speech, thus reflecting the positive outcome of surgery.

Assessment of Fluoride Content in Water and Its Impact on the Intelligence Quotient of School Children Aged 12-13 Years.

BACKGROUND: The preliminary study was undertaken with the aim to assess the effect of fluoride content in water on the Intelligence Quotient (IQ) of school children aged 12-13 years residing in areas that differ with respect to fluoride levels. MATERIALS AND METHODS: The IQ was measured using Raven's Colored Progressive Matrices in 90 children, who were life-long residents in three villages (30 children each) of similar population size but differing in the level of fluoride in drinking water. Urinary fluoride concentration was measured using the selective ion electrode technique. One-way ANOVA was used for the statistical analysis of the data. Results: Children who lived in locations with fluoride levels of 1.60, 6.70, or 2.80 parts per million in their drinking water had urinary fluoride concentrations of 1.60, 6.82, or 2.69 parts per million, and IQ scores of 16.77 + 8.24, 19.36 + 9.98, or 21.87 + 7.47, respectively. CONCLUSION: The results indicated that there was a positive correlation between excess fluoride in drinking water and IQ.

Cytomorphology, Immunophenotype, and cytogenetic profile of leukemic serous effusions.

BACKGROUND: Serous effusions (SE) in leukemic patients can be due to infections, therapy, volume overload, lymphatic obstruction or malignancy having implications on treatment and mortality. The objective of the present study is to highlight the spectrum of cytomorphology, immunophenotype, and cytogenetics in leukemic serous effusions (LSE). MATERIALS: Present study is retrospective and descriptive. We reviewed all the SE, which were reported as suspicious or positive of leukemic infiltration from 2016 to 2019 for cytomorphological features. CSF and effusions involved by lymphomas were excluded. Cyto-diagnosis was compared with primary proven diagnosis (by ancillary techniques) and disconcordant cases were analyzed. RESULTS: Out of total 9723 effusions, only 0.4% (n = 40) showed leukemic involvement and included nine cases of AML, three of B-ALL, 13 T-ALL, 2 MPAL, 6 CML, 5CLL, one each of chronic myelomonocytic leukemia and AML with myelodysplasia. The most common site of involvement was the pleural cavity (n = 30), followed by the peritoneal cavity (n = 7) and the pericardial cavity (n = 3). T -ALL (41.9%) was the most common leukemia involving pleural fluid followed by AML (23.3%). CML (42.8%) was the most common leukemia involving the ascitic fluid followed by B-ALL (28.6%). Accurate diagnosis was given on cytomorphology in 72.5% (29/40) cases and 15.0% (6/40) were reported as non-Hodgkin lymphoma. CONCLUSION: Cytology is an effective tool available to make a diagnosis of LSE. Nuclear indentations in large atypical cells and cells with eosinophilic granular cytoplasm with sparse or abundant eosinophils in the background are an important clue in favor of leukemia over lymphoma.

Histiocytic and follicular dendritic cell sarcoma: Diagnostically challenging rare entities.

BACKGROUND: Follicular dendritic cell sarcomas (FDCSs) and histiocytic sarcomas (HSs) are exceedingly rare tumors. Most of the data on those entities are based on case reports or small case series. The natural history and response to different treatment modalities have not been well established. AIMS: To analyze the clinicopathologic features, immunophenotypic profile, treatment responses and to add to the existing data on FDCS and HS. STUDY DESIGN: Retrospective descriptive study. MATERIALS AND METHOD: The study was conducted at the department of Oncopathology at a tertiary care cancer hospital in India, retrospectively within the time period of four years (2016-2019). Total eight (8) cases were diagnosed: four cases of FDCS and four cases of HS involving nodal and extra-nodal sites. Clinical, histopathological, immunohistochemistry (IHC) and therapeutic data of the eight cases were retrieved and analyzed. STATISTICS: Descriptive statistics. RESULT: Among the four patients of FDCS, two had nodal and two had extra-nodal disease. Mean tumor size was 6 cm. Tumor cells expressed CD23, CD21, CD45, CD68 and S100. One patient received adjuvant chemotherapy (Gemcitabine and Docetaxel). Median survival was 36 months. None of them developed distant metastasis. Two of the patients having HS, developed bone metastasis. Median survival was 8.5 months. CD68 was consistently expressed in all cases of HS. Other applied IHC markers were negative in all the eight cases. CONCLUSION: FDCS and HS are under-recognized and easily prone to a wrong diagnosis. Therefore, considering these rare entities in differential diagnoses and inclusion of proper IHC biomarkers are necessary to avoid potential misdiagnosis.