Is prostatic adenocarcinoma detectable by urine cytology-A multicenter retrospective review.

INTRODUCTION: Urine cytology is robust for the diagnosis of urothelial lesions, but data on the detection rates of prostatic adenocarcinoma in urine cytology is limited. In this study, a multicenter review was performed to define the clinical role of urine cytology in diagnosis of prostatic adenocarcinoma. METHODS: Cytologic diagnoses of lower tract urine cytology specimens with histology-proven prostatic adenocarcinoma from three institutions, from a period of over two decades, were reviewed. Clinicopathological parameters-tumor grade, stage, histologic features, and preanalytical factors-prostate-specific antigen (PSA) level and lesion size, were retrieved and compared with cytologic diagnoses. RESULTS: In total, 2115 urine cytology specimens from 1119 patients were retrieved. The atypia (or above/C3+) and suspicious (or above/C4+) rates were 19.48% and 3.36%. Bilobar and extracapsular involvement, lymphovascular invasion, Gleason score, and International Society of Urological Pathology grade were associated with a positive urine diagnosis (p < 0.05). The atypia (C3+) and suspicious (C4+) rates of urine cytology in patients with a PSA level of ≤4.0 ng/mL was paradoxically higher (p < 0.01), but PSA levels correlated positively with urine diagnosis at higher cutoffs (>10, >20, >50, >100 ng/mL). All these factors remained significant on multivariate analysis (p < 0.05), including a negative correlation with low-PSA (≤4.0 ng/mL, p = 0.001) and positive correlation with high-PSA (>20 ng/mL, p = 0.020). Lesion size and multifocality were not associated with urine cytology diagnosis (p > 0.05). CONCLUSION: Urine cytology showed low sensitivity in detection of prostatic adenocarcinoma. Detection rates were largely positively correlated with PSA levels but not for lesion size nor multifocality, limiting its clinical utility.

Keratinization in atypical glandular cell clusters as a cytological clue to endometrioid carcinoma on cervical cytology.

INTRODUCTION: Specific diagnosis of endometrial carcinomas on cervical cytology is difficult with few useful cytomorphological clues reported. This study reviews a cohort of cervical cytology to investigate the presence of keratinization in atypical glandular cells (AGC), an undescribed cytomorphological clue for identifying endometrial endometrioid carcinomas on cervical cytology. METHODS: Cervical cytology slides from patients with a histologic diagnosis of endometrial endometrioid carcinoma were reviewed for the presence of keratinization associated with AGCs. Corresponding histology slides were reviewed for tumour grading and degree of squamous differentiation. RESULTS: In total, 42 cases of cervical cytology specimens from 41 patients were retrieved, including 7 (16.7%) with keratinization associated with AGCs seen and 35 (83.3%) without. Comparison of histologic grading did not demonstrate an association with the presence of keratinization on cytology (p = 0.565). Corresponding histology slides were available for 37 cases. Cytologic and histologic keratinization were associated statistically (p = 0.002). Frank keratinization was seen on histologic slides of five cases, with four also showing cytologic keratinization. Area of squamous differentiation, including squamous morule formation, did not correlate with keratinization on cytologic preparation (p = 0.185). CONCLUSION: Histologic and cytologic keratinization are observed in endometrioid endometrial carcinomas. Such is reflected in cervical cytology by the presence of orangeophilic, rigid and acellular fragments within or associated with AGC clusters. Keratinization, when identified with AGCs, should be regarded as a cytologic clue suggestive of an endometroid carcinoma of endometrial origin.

Aspiration cytology of liver abscess uncovering metastatic rectal mucosal melanoma-A case report.

Aspirates of liver abscess are frequently encountered in routine practice and are often of a low index of suspicion. However, necrotic liver metastasis clinically and radiologically mimics liver abscesses, and malignant cells can be obscured in an inflammation-rich background on cytology. It is important to recognise malignant neoplasms in this scenario, in particular uncommon conditions such as metastatic mucosal melanoma.

Cytomorphologic analysis of pulmonary neuroendocrine tumors - The physical effect of abrasion and aspiration on cytomorphology.

Neuroendocrine tumors of the lung display characteristic cytomorphologic features allowing direct diagnosis. The specificity of these features in distinguishing subtypes of neuroendocrine tumors, and their differences among types of cytologic specimen poses as interpretative potential pitfalls. This study reviewed and compared bronchial, effusion fluid and fine-needle aspiration cytology specimens of neuroendocrine tumors of the lung to address these issues. Histology-proven cytology specimens of neuroendocrine tumors were reviewed for cytomorphological parameters focusing on reported specific neuroendocrine nuclear and background features. Totally, 46 cases (26 bronchial, 11 effusion and 9 aspirate specimens), corresponding to 37 small cell carcinomas, 7 neuroendocrine carcinomas and 2 carcinoids were reviewed. Nuclear moulding (n = 35/37, 95 %), naked nuclei (n = 33/37, 89 %) and marked nuclear irregularity (n = 32/37, 86 %) were the three most common features of small cell carcinoma. The only specific feature for small cell carcinoma was the lack of prominent nucleoli (p = 0.004). For pulmonary carcinoids, in addition to the above features, other features associated with neuroendocrine carcinoma reviewed including crush artifact and necrotic material were absent. Compared to bronchial and aspiration cytology, crush artifact (p < 0.001) and necrotic material (p = 0.014) were absent on effusion fluid specimens and naked nuclei were less frequently seen (p = 0.022), while prominent nucleoli were more often observed (p = 0.005). Nuclear moulding, irregularity and naked nuclei are common but not unique features to small cell carcinomas. Effusion fluid specimens have "cleaner" backgrounds while displaying greater nuclear atypia. The type of cytologic preparation/specimen is an important factor which must be considered during diagnostic interpretation.

Comparison and review of abrasive bronchial brushing versus non-abrasive aspiration, lavage and washing - Higher sensitivity but with risk of over-diagnosis for bronchial brushing.

Bronchial exfoliative cytology is classified as non-abrasive (washing, aspiration and bronchoalveolar lavage) and abrasive (brushing). Brush abrasion dislodges epithelial cells but can induce bleeding and cytomorphologic artifacts. In this study, the largest cohort to date of bronchial cytology specimens were referenced against bronchial biopsy as the reference standard. Findings in the study will be useful for selecting biopsy modality and reducing necessary procedural risks. All consecutive bronchial cytology and bronchial biopsy from 1995 to 2022 were retrieved. The diagnoses were reviewed and categorized into five-tiered diagnostic categories to compare diagnostic agreement and concordance. Review of 14,148 specimens yielded 3963 non-abrasive, 2378 abrasive cytology specimens matched to biopsy, with 4355 matches between non-abrasive and abrasive cytology specimens. Agreement between non-abrasive and abrasive cytology was moderate (κ = 0.580), and similar when referenced against biopsy (κ = 0.456 (non-abrasive), κ = 0.498 (abrasive)). Abrasive bronchial cytology showed a higher percentage of malignant diagnosis (20.95 % vs. 12.63 %, p < 0.001) and over-diagnosis rate (36.40 % vs. 29.79 %, p < 0.001), but higher sensitivity (0.747 vs. 0.572, p = 0.002). For subgroup analysis of transbronchial biopsies, matched abrasive cytology showed higher discordant rates (p < 0.05) and lower accuracy (0.907 vs. 0.873, p = 0.020). With the added bleeding risk associated with brushing, abrasive techniques may only be preferable in cases with clinical or bronchoscopic suspicion of malignancy, in particular endobronchial mucosal lesions. For routine bronchoscopy, non-abrasive bronchial cytology appears to be adequate.

Bronchial cytology of pulmonary adenoid cystic carcinoma - A multi-institute series with emphasis on immunocytochemistry.

BACKGROUND: Pulmonary adenoid cystic carcinoma (AdCC) is a central and superficial primary lung neoplasm, well-suited for sampling by bronchial cytology. This study aims to review the cytologic features of pulmonary AdCC on bronchial cytology, and to report an experience of applying immunocytochemistry on this rare entity. METHODS: A multi-institute review of bronchial cytology specimens from histologically proven pulmonary AdCCs was performed. Published cases of bronchial cytology of pulmonary AdCC were reviewed. The cytologic features and immunocytochemical profile for pulmonary AdCC was summarized and compared with pertinent differentials. RESULTS: A total of 16 specimens from eight patients were retrieved. The initial cytologic diagnoses were negative (n = 7), atypia (n = 6), suspicious (n = 2) and AdCC (n = 1). Retrospective review showed eight bronchial cytology specimens (including five cases of atypia) with tumor cells present. The tumor cells displayed small basaloid nuclei with occasional small nucleoli, mild nuclear atypia, and scanty cytoplasm. Architectural patterns observed included clusters, tubules, solid sheets, three-dimensional balls, papillary-like fronds, and complex cribriform structures. Basement-membrane-like material, free or associated with tumor cells, were seen in all cases. Immunocytochemistry was performed in one specimen. MYB was positive. TTF-1, synaptophysin and chromogranin were negative. Epithelial and basal markers demonstrated a dual cell population. Literature review yielded 28 cases. Cytologic features described were similar except for cytoplasmic vacuolation in one case. CONCLUSION: Basement membrane-like material is specific for AdCC. MYB positivity, TTF-1 and neuroendocrine marker negativity, support a diagnosis of AdCC. Other immunocytochemistry and cytologic features overlap significantly with adenocarcinoma and small cell carcinoma of lung.

Detection of early (T1) lung cancers and lepidic adenocarcinomas in sputum and bronchial cytology.

BACKGROUND: The lung is an extensively epithelialized organ, producing ample exfoliated material for sputum and bronchial cytology. In view of the updates in the World Health Organization classification of early (T1/≤ 3 cm) lung cancer with respect to adenocarcinomas with lepidic pattern, this study retrospectively reviews sputum and bronchial cytology paired with resection-confirmed lung cancers. METHODS: A computerized search for all lung resection specimens of carcinomas over a 20-year period was performed. Cytologic diagnoses of corresponding sputum and bronchial cytology were classified into five-tiered categories (C1-insufficient/inadequate, C2-benign, C3-atypia, C4-suspicious and C5-malignant). Reports and slides of the resection specimen were reviewed for reclassification of T1 cancers. RESULTS: Totally 472 and 383 sputum and bronchial cytology specimens respectively were included. Sensitivity for T1 lesions on sputum cytology were 10.6 %, 2.1 % and 0.5 % at cutoffs of atypia/C3, suspicious/C4 and malignant/C5 categories, lower than bronchial cytology (35.1 %, 15.5 %, 8.1 %; p < 0.001). T1 lesions correlated with lower detection rates, whereas squamous cell carcinoma histology, larger size and bronchial invasion were associated with increased detection rates in sputum and bronchial cytology (p < 0.050). Detection rates for abrasive bronchial cytology (brushing) were overall higher (p = 0.018- < 0.001), but on subgroup comparison, non-abrasive (aspiration, lavage and washing) cytology demonstrated favorable trends (p = 0.063-0.088) in detecting T1 lesions. Adenocarcinomas with lepidic pattern had lower suspicious/C4 (p = 0.040) or above and malignant/C5 (p = 0.019), but not atypia/C3 or above (p = 0.517) rates. CONCLUSIONS: Most adenocarcinomas with lepidic pattern are only diagnosed as atypia/C3 on cytology. With its modest sensitivity, interpretation of negative and indeterminate cytology results mandates caution.

Fine needle aspiration cytology of metastatic carcinomas with papillary architecture: A systemic assessment of clinical, cytological and immunohistochemical parameters.

BACKGROUND: Papillary structures are frequently encountered in metastatic carcinomas from various organs and tumours of different histotypes. This study aims to investigate the predictive value of fine needle aspiration cytology (FNAC), immunohistochemistry (IHC) and the clinical parameters which can be examined in the assessment of the primary sites of metastatic carcinomas with papillary architecture. METHODS: FNAC samples of metastatic carcinomas with papillary architecture were evaluated for overall cellularity, epithelial cohesion, background features, papillary architecture, cytology and IHC. The corresponding clinical information was also reviewed. RESULTS: A total of 130 cases were included. The most common primary sites were thyroid (38.5%), lung (30.8%) and gynecological organs (22.3%); the others were pancreaticobiliary, urothelial, colorectal, and esophageal. Age (P = 0.039), biopsy site (P < 0.001) and laterality (P = 0.006) correlated with primary site. Papillary structures were confirmed on biopsy/excision of most cases (n = 85/87, 97.7%). Thyroid primaries exhibited broad papillary stalks, thin lining epithelium, fewer epithelial polymorphs, and the presence of background giant cells and histiocytes (P = 0.021- < 0.001). Low-grade cytological features, nuclear grooves and inclusions (P < 0.001) were seen in thyroid primaries. High-grade features (P < 0.001-0.49), multinucleated tumour cells, apoptotic bodies and mitoses (P < 0.001-0.49) were more common in lung/gynecological primaries. Multivariate analysis identified nuclear/cytoplasmic ratio, chromatin character, the presence of nuclear grooves and mitosis as independent features (P = 0.001-0.024). TTF1/TGB/PAX8 panel results showed good agreement with the cytological assessment and site of primary. CONCLUSION: Papillary structures and cytological features are reproducible in FNAC assessment of metastases and their corresponding primary sites. Cytological features, IHC and clinical information are invaluable in determining the primary site.

Cytomorphologic comparison of upper urinary tract urothelial carcinomas and renal cell carcinomas on urine cytology.

INTRODUCTION: Compared to urothelial carcinomas (UCs), the cytomorphology of renal cell carcinomas (RCCs) is underdescribed. This study aims to investigate whether UCs and RCCS of the upper urinary tract can be differentiated cytologically, and to identify distinguishing cytomorphological features. METHODOLOGY: Consecutive urine cytology specimens with atypical/C3, suspicious/C4 or malignant/C5 diagnoses matched with a nephrectomy or ureterectomy specimen with UC or RCC over a 15-year period were reviewed for cellularity, architecture, background composition and cytomorphologic features. RESULTS: Totally 132 specimens were retrieved, comprising 24 RCCs and 108 UCs. Clear cell RCC (CCRCC) (n = 18) was the most common RCC. Urine cytology specimens from UC showed a trend of higher cellularity (p = 0.071) against RCC and was significant in subgroup analysis with CCRCC (p < .001). Epithelial structures in sheets, tubules, and papillae were exclusive in specimens of UC (p < .05). For background features, squamous cells were more common for RCC (p = .006) including CCRCC (p = .003), whereas polymorphs (p = .011) and necrotic material (p = .010) were associated with UC. Average nuclear size was larger and nuclear size variation (p < .001) and nuclear-cytoplasmic ratio (p = .001) were greater in UC (p = .001) than RCC. Comparing RCC to high-grade UCs only, nuclear-cytoplasmic ratio maintained statistical significance (p = .006) while average nuclear size showed a trend (p = .063). CONCLUSION: A clean background free of tumor necrosis and polymorphs, and the lack of complex tumor fragments favors RCC. UCs also display larger nuclear size, higher nuclear size variation and nuclear-cytoplasmic ratio. These cytomorphological features with corroboration of clinical/radiological findings, can aid in raising a diagnosis of RCC.

Adequacy Assessment in Lymph Node Aspirates: An Exploratory Cytomorphologic Analysis of Negative Cervical Node Aspirates of Head and Neck Carcinomas.

INTRODUCTION: Fine-needle aspiration cytology (FNAC) of lymph node is sensitive for detection of metastatic carcinoma but not without a significant false-negative rate. This study reviews clinicocytological features of negative node aspirates to identify predictive factors for establishing adequacy criteria. METHODS: Negative FNAC specimens matched with neck dissection from a primary diagnosis of head and neck squamous cell, or undifferentiated (nasopharyngeal) carcinoma were reviewed for clinical and cytological parameters including lymphoid, inflammatory, and background components. RESULTS: Slides from 86 lymph node aspirates including 50 positive for metastasis on follow-up were retrieved. Higher total lymphocyte count, lymphoid fragment count, germinal center fragment count, undifferentiated histology, presence of histiocytes and absence of blood were associated with a true negative cytologic diagnosis (p < 0.05), but not node size or location (p > 0.05). Undifferentiated histology, small lymphoid and germinal center fragments were independent factors indicative of a true negative diagnosis (p < 0.05). Large lymphoid fragments (p = 0.052) demonstrated a trend. Assessment of lymphoid components over five hotspots high-power fields (HPFs) was more robust in predictive value than only one hotspot. Receiver operating characteristic curve identified >10 small lymphoid, >20 large lymphoid and >2 germinal center fragment per five HPFs as optimal adequacy thresholds. Stricter total lymphocyte count cutoff accompanies increase of diagnostic accuracy, up to 0.67 for ≥5 HPFs with >500 lymphocytes. CONCLUSION: Total counts of lymphoid and germinal center fragments from multiple HPFs are useful in adequacy assessment of lymph node aspirates and improve diagnostic performance of FNAC in exclusion of metastatic carcinoma.

Prevalence and interpretation of AFF immunostain of DEK::AFF2 fusion-associated papillary squamous cell carcinoma in a retrospective cohort of recurrent sinonasal papillomas.

DEK::AFF2 fusion-associated papillary squamous cell carcinoma is a novel entity characterized by its unique translocation and malignant clinical course. In this study, AFF immunohistochemistry (IHC) was performed in recurrent sinonasal papillomas for reviewing the prevalence of undiagnosed DEK::AFF2 carcinomas and to investigate the performance of AFF IHC in diagnosis of DEK::AFF2 carcinomas. Recurrent sinonasal papillomas after surgical excision in a two-decade period were retrieved. Histologic slides were reviewed for features of DEK::AFF2 carcinoma. AFF IHC was performed, and cases with any (> 1%) nuclear positivity were validated by DEK break apart fluorescence in situ hybridization. Totally 43 cases were included, comprising 28 inverted, 6 exophytic, one oncocytic, and 8 non-specified sinonasal papillomas. Five (11.6%) cases exhibited positivity to AFF IHC. Three cases exhibited patchy weak to moderate staining intensity predominantly in a granular cytoplasmic pattern. Two cases exhibited strong and diffuse (> 90%) nuclear staining. Cases showing weak staining were negative for DEK rearrangement, while those with strong staining were positive. Both cases of DEK::AFF2 carcinoma showed aggressive behavior with extensive local invasion and nodal metastasis. Background stromal plasma cells, when present, consistently showed strong and diffuse staining. AFF IHC was further performed in plasmacytoma samples as control and showed strong and diffuse immunoreactivity. A significant minority of recurrent sinonasal papillomas represent DEK::AFF2 carcinomas. Granular, cytoplasmic, or incomplete AFF staining should be considered as negative. In view of the rarity of DEK::AFF2 carcinomas, plasma cells and plasma cell neoplasms are potential for internal and surrogate external controls.

Cytomorphological Assessment in Aspirates of Ductal Carcinoma in situ: Correlations with Histopathologic Grade, Architectural Pattern, and Invasion.

INTRODUCTION: Fine-needle aspiration biopsy (FNAB) of the breast is an effective and widely adopted diagnostic technique. Histopathologic grading of ductal carcinoma in situ (DCIS) has prognostic significance. In this current study, FNAB of DCIS was reviewed to identify parameters that predict grading, histopathologic architecture, and presence of invasion in DCIS. METHODS: Aspirates from histopathology-proven cases of DCIS were retrieved and reviewed for cytomorphologic parameters including cellularity, composition, epithelial fragment architecture cellular/nuclear features. RESULTS: In total 104 aspirates were reviewed. Cytopathologic cellular features - large nuclear size (p = 0.005), prominent nucleoli (p = 0.011), increased nuclear membrane irregularity (p = 0.043), high variation in nuclear size (p = 0.025), and presence of apoptotic figures in epithelial structures (p < 0.001); and background debris (p = 0.033) correlated with a high-grade diagnosis. Cytoplasmic vacuolation (p = 0.034) was seen exclusively in non-high-grade aspirates. Epithelial fragment architecture did not correlate with grading. A predominance (≥50%) of solid aggregates and papillary fragments on FNAB correlated with histopathologically solid (p = 0.039, p = 0.005) and papillary (p = 0.029, < p = 0.001) patterns. No parameter showed correlation with invasion. CONCLUSION: FNAB is effective in predicting DCIS grading. Epithelial fragment architecture assessment is limited to papillary or solid types, and FNAB cannot predict focal invasion in DCIS.

Predictors of an informative or actionable cytological diagnosis on repeat breast aspiration after an insufficient aspirate: a multicentre retrospective review.

An insufficient/inadequate diagnosis on fine-needle aspiration cytology (FNAC) of the breast is not an uncommon diagnostic dilemma. This study aims to review the rate and clinical features predicting an informative or actionable diagnosis on repeating breast aspiration after an insufficient aspirate. METHODS: Unsatisfactory/insufficient/inadequate or equivalent breast aspirates were retrieved from the involved institutions, and those with a repeat aspiration performed within 365 days were included. Clinical and radiological information were retrieved. Available cytological slides were reviewed. RESULTS: Totally 539 paired aspirates were retrieved, with 61.2% (n=330/539) and 10.9% (n=59/539) cytological diagnosis being informative (not insufficient) and actionable (not insufficient nor benign) on repeat aspiration. Younger age (p=0.005) was associated with an informative diagnosis and prior radiotherapy (p=0.097) and insufficient aspirates performed under free-hand (p=0.097) trended with an actionable diagnosis. Radiological findings of calcification (p=0.026) and hyperechogenicity (p=0.045), a small lesion size on initial (p=0.037) and repeat (p=0.059) radiological assessment and interval size increment (p=0.019) correlated with informative/actionable diagnoses. Cytomorphological parameters, except for a trend with crushing artefact (p=0.063), do not correlate with the cytologic diagnosis of the repeat aspirate. CONCLUSIONS: Repeating breast FNAC on patients after an insufficient diagnosis yields an informative ('sufficient') result in over 60% of cases. Small lesions with calcification, hyperechogenicity and/or interval size increment are more likely to yield diagnostic results on repeat aspiration and indicate select patients suitable for repeat FNAC over more invasive procedures. The lack of associations with cytomorphological parameters cautions against overinterpretation of insufficient breast aspirates.

Single-cell multiplex immunocytochemistry in cell block preparations of metastatic breast cancer confirms sensitivity of GATA-binding protein 3 over gross cystic disease fluid protein 15 and mammaglobin.

BACKGROUND: Metastatic breast cancers are frequently encountered in cytology and require immunocytochemistry (ICC). In this study, traditional and multiplex ICC (mICC) for GATA-binding protein 3 (GATA3), gross cystic disease fluid protein 15 (GCDFP15), and mammaglobin (MMG) were performed with the aim of validating mICC in cell blocks, with further single-cell expression pattern analysis to identify the single markers and combinations of markers most sensitive in subtypes of breast cancer. METHODS: GATA3, GCDFP15, and MMG were paired with OptiView 3,3'-diaminobenzidine and Ventana DISCOVERY Purple and Blue, respectively, with cyclical and serial staining. Bright-field imaging was performed with the Mantra 2 system and analyzed with the inForm Tissue Finder (Akoya Biosciences). Cell detection and phenotyping were further confirmed by two pathologists. RESULTS: In the 36 cases studied, traditional ICC and mICC demonstrated good concordance (kappa coefficient, >0.5; p < .01) at three cutoffs (1%, 5%, and 50%), except for GATA3 at the 1% cutoff. Single-marker positivity outnumbered double-marker positivity and the exceedingly rare triple-marker positivity (<3%). GATA3 was the leading single marker-positive phenotype in all breast cancer subtypes, except for MMG in estrogen receptor-positive, progesterone receptor-positive, and human epidermal growth factor receptor 2-positive (ER+/PR+/HER2+) breast cancers. Limited to two markers, GATA3/MMG included the greatest number of tumor cells for luminal breast cancers (ER+/PR+/HER2+, 60.6%; ER+/PR+/HER2+, 31.4%), whereas HER2-overexpressed breast cancers (27.4%) and triple-negative breast cancers (26.4%) favored the combination of GATA3/GCDFP15. CONCLUSIONS: For a single marker, GATA3 displayed the highest sensitivity. The addition of MMG for hormone receptor-positive breast cancers and GCDFP15 for hormone receptor-negative breast cancers further increased sensitivity. The low proportion of multimarker-positive cells suggested that the coexpression observed with traditional ICC is attributable to intratumoral heterogeneity, not genuine coexpression.

Comparison of Claudin-4, BerEP4, Carcinoembryonic Antigen and MOC31 in Serous Fluids Metastases Demonstrate High Sensitivity of Claudin-4 at Low Cellularity.

INTRODUCTION: Claudin-4 has been described as a highly sensitive immunocytochemical marker for detection of metastatic carcinoma cells in effusion cytology specimens. This study aims to challenge the performance of claudin-4 in different types of malignancies and low cellularity specimens, by comparison with other markers in a large cohort of carcinomatous effusion specimens. METHODOLOGY: Cell block preparations from peritoneal and pleural fluid specimens were retrieved, with malignant (carcinoma) diagnoses confirmed by review of hospital diagnosis code and pathology reports. Claudin-4, BerEP4, CEA, and MOC31 immunocytochemistry were performed and scored by expression proportion and intensity. Tumor cellularity was assessed for subgroup analysis of low cellularity specimens. RESULTS: Totally 147 specimens (70 pleural, 77 peritoneal) of 68 lung, 62 breast, 9 gynecological, and 7 gastrointestinal carcinomas were retrieved. The average proportion expression of claudin-4 was highest (89.6%, vs. CEA 40.5%, BerEp4 18.6%, MOC31 16.8%) and the percentage of strong expression was highest for claudin-4 (72.1%). Expression levels of claudin-4 were consistently higher than other markers in subgroups of all primary sites. The difference was more significant for low cellularity specimens. High (≥50%) proportion expression was seen for 96.61% of cases for claudin-4 (vs. BerEp4 8.77%, CEA 46.55%, MOC31 8.77%, p < 0.001). These factors contributed to a low concordance between claudin-4 and BerEp4, CEA and MOC31 (K = 0.010-0.043). CONCLUSION: Claudin-4 is more sensitive than CEA, BerEp4 and MOC31, suitable for low cellularity specimens of most types of metastatic carcinoma and is a robust immunocytochemical marker for carcinoma that can be used solitarily.

Urine cytology in the detection of renal cell carcinomas - a territory-wide multi-institutional retrospective review of more than 2 decades.

INTRODUCTION: Compared with urothelial lesions of the upper urinary tract, the diagnostic performance of urine cytology in detection of renal cell carcinomas is underreported. This study aims to establish the role of urine cytology in the assessment of renal carcinomas by a multi-institute review of urine cytology from nephrectomy confirmed renal cell carcinomas, referenced against renal urothelial and squamous cell carcinomas. METHODS: Records of nephrectomy performed from the 1990s to 2020s at three hospitals were retrieved and matched to urine cytology specimens collected within 1 year prior. Patient demographics, specimen descriptors, and histology and staging parameters were reviewed and compared against cytologic diagnoses. RESULTS: There were 1147 cases of urine cytology matched with renal cell carcinomas, with 666 renal urothelial/squamous carcinomas for comparison. The detection rate for urothelial/squamous (atypia or above [C3+]: 63.1%; suspicious or above [C4+]: 24.0%) were higher than renal cell carcinoma (C3+: 13.1%; C4+: 1.5%) (p < 0.001). The positive rate for upper tract urine exceeded other collection methods at 45.0% (C3+) and 10.0% (C4+) (p < .01). Other factors associated with increased positive rates were male sex, collecting duct carcinoma histology, nuclear grade, and renal/sinus involvement (p < .05). Multivariate analysis revealed additional positive correlations with presence of sarcomatoid tumor cells, lymphovascular invasion, and perinephric fat involvement (p < .05). Larger lesion size and higher urine volume did not improve detection rates (p < .05). CONCLUSIONS: The detection rate of renal cell carcinomas is suboptimal compared with urothelial carcinomas, although urine samples collected from cystoscopy or percutaneous nephrostomy significantly outperformed voided urine specimens.

Liposarcoma Involving Serous Fluid Cavities-A Case Series Illustrating Clinical Implications and the Diagnostic Role of Exfoliative Cytology.

Introduction: Cytological diagnosis of sarcomas requires detailed cytomorphological assessment and integration of immunocytochemistry and/or molecular testing. The role of exfoliative cytology, as compared to aspiration cytology, is less understood. This case series describes well-differentiated/dedifferentiated liposarcomas in effusions, with cytomorphological features, ancillary test results and clinical outcomes detailed. Methods: A computerized search of the department pathology archives was performed for sarcomatous effusions with histological diagnosis or clinical history of well-differentiated/dedifferentiated liposarcoma. Clinical progress, cytology slides, immunocytochemistry and molecular test results were reviewed. Results: Six patients were identified. In 5 patients with clinical follow up, 4 (80%) were deceased within 5 months of malignant effusion. One patient was alive with 12 years disease-free survival after radical resection with adjuvant radiotherapy. Three patients showed dedifferentiation on histology, and high-grade (dedifferentiated) tumor cells were present in effusion cytology of 2 patients. Two showed well-differentiated components only on biopsy, but high-grade (dedifferentiated) tumor cells were identified in cytology. The high-grade tumor cells displayed marked nuclear irregularity, enlargement, size variation, with macronucleoli and multinucleation. Well-differentiated lipomatous components were demonstrated in 4 patients (66.7%), comprising of multivacuolated lipoblasts and atypical lipocytes. CDK4 and MDM2 immunoreactivity in all 3 cases with cell blocks, and CDK4 and MDM2 amplification in one were successfully demonstrated. Conclusion: Lipomatous and dedifferentiated components can be sampled and cytomorphologically identified on effusion fluids of liposarcomas, with sufficient cellularity for immunocytochemistry and molecular testing. Although generally associated with poor prognosis, long disease-free survival with sarcomatous effusion is possible with radical surgery and adjuvant treatment.

The First Report of Cytology of DEK::AFF2 Fusion-Associated Papillary Squamous Cell Carcinoma on Fine-Needle Aspiration.

DEK::AFF2 fusion-associated papillary squamous cell carcinoma is a recently characterized sinonasal malignancy defined by its unique translocation. DEK::AFF2 carcinomas may be deceptively monotonous and lack keratinization, resembling transitional epithelium. The lack of traditional cytological atypia presents diagnostic challenges. Our case describes the first report of fine-needle aspiration cytology of a lymph node involved by DEK::AFF2 carcinoma in a patient with previously resected sinonasal inverted papilloma with carcinomatous transformation six years prior to presentation. This aspirate consisted of a lymphoid-rich background admixed with a moderate amount of epithelial cells arranged in cohesive structures of variable size, including large sheets. The tumor cells resembled those of the corresponding biopsy, featuring mildly hyperchromatic nuclei with fine to vesicular chromatin. Lesional cells lacked keratinization, mitoses, or hyperchromasia. Our finding suggests that in nodal aspirates of patients with a history of sinonasal-type papillomas, especially those with prior malignant transformation or atypia, there should be consideration for the possibility of DEK::AFF2-related primary. When in doubt, DEK FISH of AFF2 immunohistochemistry should be performed for confirmation.

Application of algorithmic cytomorphological assessment and immunocytochemistry with the international system for reporting serous fluid cytopathology on pericardial fluid cytology.

AIMS: The international system for reporting serous fluid cytopathology (ISRSFC) set forth a five-tiered reporting system with comprehensive validation on pleural and peritoneal fluid cytology. An algorithmic approach for cytomorphological assessment and immunocytochemistry was also described in ISRSFC. Limited data on pericardial fluid are supportive but would benefit from further investigation. METHODS: Consecutive pericardial fluid cytology over a 4-year period was reviewed by multiple board-certified pathologists according to the ISRSFC. Cytomorphology and immunocytochemistry were assessed sequentially, with respective diagnostic performances computed and compared. Literature review was performed. RESULTS: In total 358 specimens, including 53 with immunocytochemistry available, were reviewed. There were 137 benign and 221 malignant (MAL) cases. The risks of malignancy were 23.5% non-diagnostic (ND), 29.2% negative for malignancy (NFM), 56.0% atypia of undetermined significance (AUS), 82.6% suspicious for malignancy (SFM) and 99.2% (MAL) for cytomorphological assessment, improving to 23.5% (ND), 29.1% (NFM), 56.8% (AUS), 78.9% (SFM) and 99.3% (MAL) incorporating immunocytochemistry. Ten cases (2.8%) received a change in diagnosis after review of immunocytochemistry. All revisions of diagnostic category were appropriate upgrades/downgrades referenced against clinical information. Cytomorphological typing was accurate for adenocarcinoma (n=81/83, 97.6%), while other carcinomas and lymphomas required immunocytochemistry. Certain subcategories within AUS and SFM pertaining to bland indeterminate epithelial cells or mucinous material were not seen for pericardial fluid. CONCLUSIONS: The ISRSFC shows robust diagnostic performance for pericardial fluid cytology. For pericardial effusion, disease composition and applicable cytological subcategories differ from its peritoneal and pleural counterparts. Incorporating immunocytochemistry by an algorithmic approach improves diagnostic accuracy. Cytomorphology is accurate for identifying adenocarcinomas, but further typing necessitates immunocytochemistry is necessary.