Pheochromocytoma presenting as a pancreatic mass: Avoiding a dangerous pitfall in endoscopic ultrasound-guided fine needle aspiration biopsy using GATA3 immunostain.

Pheochromocytomas and sympathetic paragangliomas are rare tumours arising from chromaffin cells, producing catecholamines in various amounts. Fatal hypertensive episodes may occur perioperatively, which are preventable by alpha adrenergic receptor blockers. The perioperative mortality rate of diagnosed versus undiagnosed catecholamine-producing tumours is significant, considering that only a minority of tumours develop metastasis. Herein we describe a case of a primary adrenal pheochromocytoma referred to as a pancreatic tumour, successfully diagnosed by endoscopic ultrasound-guided fine needle aspiration biopsy, with a distinct morphology (prominent nuclear anisonucleosis, intranuclear pseudoinclusions, and multinucleation) and immunohistochemical signature.

Time-related changes in cell morphology and biomarker immunoreactivity for cells stored in a buffer-based cell medium.

OBJECTIVE: Buffer-based cell media (BBCM) are a valuable tool in the post-collection processing of cytology samples, though with poorly defined effects on cell properties. In this study, time-related changes in cell morphology and biomarker immunoreactivity were evaluated for cells stored at room temperature in a BBCM prepared with bovine serum albumin (BSA) and ethylene diamine tetraacetic acid (EDTA). METHODS: Cytospins were prepared at five consecutive 24-hour intervals (0, 24, 48, 72, 96) from three human cell lines (MCF7, SK-MEL-28, FaDu) suspended and stored in BBCM. Preservation of cell morphology was evaluated on Papanicolaou-stained cytospins from the percentages of apoptotic cells. Preservation of immunoreactivity was evaluated for cytokeratins, oestrogen receptors, Ki67, and melanoma markers from the percentages of cells positive for the corresponding immunocytochemical reactions. RESULTS: Cell morphology was well preserved for the majority of cells of the three lines stored for 24 and 48 hours (93%, 97%, 98% and 62%, 81%, 88%, respectively), while the majority of cells were apoptotic after 72 and 96 hours (70%, 47%, 39% and 77%, 70%, 59%, respectively). The immunoreactivity of cytokeratins remained unchanged during the entire 96 hours, while that of melanoma markers (S100, HMB45, Melan-A) decreased by 27%, 2%, and 3%, respectively. The immunoreactivity of oestrogen receptors and Ki67 decreased by 29% and 17% after the first 24 hours, and was completely lost after 96 hours. CONCLUSIONS: A BBCM with the addition of BSA and EDTA facilitates good preservation of cell morphology and immunoreactivity of biomarkers for up to 48 hours at room temperature.

Preservation of biomarkers immunoreactivity on cytospins protected with polyethylene glycol.

INTRODUCTION: The aim of this retrospective study was to evaluate the preservation of biomarkers immunoreactivity on cytospins protected with polyethylene glycol (PEG). METHODS: In two independent cytopathology laboratories, immunocytochemical reactions were retrospectively evaluated on methanol-fixed and PEG-protected cytospins stored at room temperature (RT) for different time periods and compared with immunocytochemical reactions on corresponding baseline methanol-fixed cytospins. Semi-quantitatively assessed immunoreactivity, using scores from 0 to 3, was considered reduced if two sequential scores were lowered by at least one point. RESULTS: Immunocytochemical reactions for 40 biomarkers with membrane (10), cytoplasmic (22) and nuclear (8) localisation were performed on 921 slides prepared from 183 cytological samples. For the majority of biomarkers (29/37, 78%), immunoreactivity on PEG-protected cytospins stored at RT remained unchanged in the first 12 months. Immunoreactivity for GFAP, p40 and hepatocyte antigen was monitored and remained unchanged for 1, 8 and 7 months, respectively. Partial or complete loss of immunoreactivity on PEG-protected cytospins stored for less than 12 months was found on a single sample out of the total evaluated for CD3 (1/7), CD30 (1/4), CD45 (1/10), CK5/6 (1/7), MelanA (1/7) and vimentin (1/7), while more frequent changes of immunoreactivity were found for Ki67 (4/7) and p63 (2/7). CONCLUSION: Immunoreactivity on cytospins protected with PEG and stored at RT is well-preserved for at least 12 months for the majority of biomarkers.

Cell block practices in European cytopathology laboratories.

BACKGROUND: There are numerous methods and procedures described for the preparation of cell blocks (CBs) from cytological samples. The objective of this study was to determine current practices and issues with CBs in European laboratories. METHODS: A link to an online survey, with 11 questions about CB practices, was distributed to cytology laboratories via participants of United Kingdom National External Quality Assurance Service for Cellular Pathology Techniques and national representatives in the European Federation of Cytology Societies. RESULTS: A total of 402 laboratories responded completely (337/402, 84%) or partially (65/402, 16%) to the survey by February 4, 2022. The most common CB practice is embedding cell pellets using plasma and thrombin (23.3%), agar (17.1%), Shandon/Epredia Cytoblock (11.4%), HistoGel (7.9%), and Cellient (3.5%). Other methods such as CytoFoam, albumin, gelatin, Cytomatrix, and collodion bags are rarely used (1.0%, 0.7%, 0.7%, 0.3%, and 0.2%, respectively). CBs are also prepared from naturally occurring clots or tissue fragments (29.5%) and cells scraped from unstained or prestained smears (4.4%). The most frequent issues with the CBs in a daily cytology practice are low cellularity (248/402, 62%) and dispersed cells (89/402, 22%), regardless of the CBs preparation method or how the samples for embedding were selected. CONCLUSIONS: There is a great variability in CB practices in European laboratories with low cellular CBs as the main issue. Additional studies are mandatory to evaluate and improve performance and cellular yield of CBs.

Optimization of pre-analytical and analytical steps for DNA and RNA analysis of fresh cytology samples.

BACKGROUND: Different cytology preparations can be used for molecular diagnostics, however the influence of pre-analytical and analytical steps on the results are not yet well defined. We aimed to determine optimal steps for efficient extraction of DNA and RNA from fresh cells for molecular diagnostics. METHODS: MCF7 and FaDu human cell lines, were used as a model to determine fresh cells storage conditions (temperature: 25°C, 4°C, -20°C, -80°C; duration: 0 h, 4 h, 12 h, 24 h, 48 h) and optimal nucleic acids extraction method. Besides, the minimal number of total cells and minimal percentage of mutated cells needed for successful extraction of nucleic acids and subsequent determination of present mutation were evaluated. RESULTS: Extraction of nucleic acids using spin columns yielded the highest quantity and quality of nucleic acids. Isolation of nucleic acids was feasible in all storage conditions, however higher temperature and longer duration of fresh cells storage were associated with lower quality of isolated nucleic acids and similar quantification cycle of housekeeping genes. Successful molecular testing was feasible with least 104 cells, while specific mutation was detected in as low as 5% of mutated cells. CONCLUSIONS: Our cell line model, mimicking fresh cytology samples, showed that quantity of extracted either DNA or RNA declined with higher temperatures and longer duration of storage but regardless of the storage conditions, we successfully detected both housekeeping genes and mutated gene using qPCR.

Inter- and intraobserver agreement in whole-slide digital ThinPrep samples of low-grade squamous lesions of the cervix uteri with known high-risk HPV status: A multicentric international study.

BACKGROUND: High-risk human papilloma virus (HR HPV) testing and liquid-based cytology are used for primary cervical screening. Digital cytology, based on whole-slide scanned samples, is a promising technique for teaching and diagnostic purposes. The aim of our study was to evaluate the interobserver and intraobserver variation in low-grade squamous lesions, HR HPV status bias, and the use of whole-slide scanned digital cervical cytology slides. METHODS: Fifteen expert cytopathologists evaluated 71 digitalized ThinPrep slides (31 atypical squamous cells of undetermined significance [ASC-US], 21 negative for intraepithelial lesion or malignancy, and 19 low-grade squamous intraepithelial lesion cases). HR HPV data were accessible only in the second round. RESULTS: In interobserver analysis, Kendall's coefficient of concordance was 0.52 in the first round and 0.58 in the second round. Fleiss' kappa values were 0.29 in the first round and 0.31 in the second round. In the ASC-US category, Fleiss kappa increased from 0.19 to 0.22 in the second round and the increase was even higher expressed by Kendall's coefficient: from 0.42 to 0.52. In intraobserver analysis, personal scores were higher in the second round. CONCLUSIONS: The interobserver and intraobserver variability in low-grade squamous lesions was within fair agreement values in the present study, in line with previous works. The comparison of two rounds showed that expert cytopathologists are generally unbiased by the knowledge of HR HPV data, but that being informed of the HR HPV status leads to a better agreement. Stain quality and back discomfort were highlighted as factors affecting digital cytopathology use.

A novel combined animal tissue model for freehand and ultrasound-guided fine needle aspiration biopsy and smear preparation techniques training.

OBJECTIVE: A variety of models are used for fine needle aspiration biopsy (FNAB) and smear preparation techniques training: human, animal and silicon models or combined models. We present fresh animal tissues as models for freehand and ultrasound (US)-guided FNAB technique training, enabling an integrated approach from tumour detection to smear evaluation. METHODS: We introduced a novel combined animal tissue model using dietary animal meat with covering skin as a substrate. Animal liver tissue of various sizes, representing tumour, was inserted into the various layers of the substrate (subcutaneous fat, muscle tissue, proximity of bone). Freehand and US-guided FNAB smear preparation, including fixation, was then performed and assessed. RESULTS: The use of a combined animal tissue model for 6 freehand and 3 US-guided FNAB sessions showed a statistically significant improvement in the US-guided FNAB retrieval of liver tissue (Fisher's exact test, p =  .0216), in smear preparation technique reflected in a decrease in the number of too thick smears after freehand FNAB (Fisher's exact test, p  =  .0070), in the overall number of smears satisfactory for evaluation by US-guided FNAB (Fisher's exact test, p =  .0206) and in the number of flawless smears obtained in the freehand FNAB training sessions (Fisher's exact test, p =  .0020). CONCLUSIONS: A unique advantage of the presented model encompassing various layers of animal tissues with covering skin, offers an integrated approach for FNAB training from "tumour" detection, puncture precision, to smear preparation and cytological evaluation for a wider audience and does not compromise patient safety.

Stratified Mucin-Producing Intraepithelial Lesion (SMILE) of the Uterine Cervix: High-Risk HPV Genotype Predominance and p40 Immunophenotype.

Stratified mucin-producing intraepithelial lesion (SMILE) is a rare high-grade cervical precancerous lesion designated a variant of adenocarcinoma in situ (AIS) in the WHO classification. We aimed to determine HPV genotypes, immunohistochemical phenotype and mucin presence in SMILE. Between 2010 and 2018, SMILE was diagnosed in 34 out of 6958 (0.5%) cervical biopsies, in 23 patients. Twenty-six tissue samples from twenty-one patients were available for further analysis, including 13 with SMILE alone, 12 with SIL and/or AIS and one with HSIL, AIS and endocervical adenocarcinoma. HPV genotyping was performed using the Seegene Anyplex II HPV 28 assay. Of the 26 samples, a single HPV genotype was identified in the majority of cases (n = 22), including 12/13 SMILEs associated with SIL/AIS. All but one were high-risk HPV genotypes (23/24; 96.8%). We identified seven different HPV genotypes, the most common being HPV16 (n = 10; 43.5%), HPV18 (n = 8, 34.8%) and HPV 31 (n = 5, 21.7%). All SMILEs showed a strong positive reaction to p16, CK7, CK19 and high Ki67 expression comparable to adjacent HSIL and/or AIS if present. SMILE showed variable mucin presence and p40-positive squamous differentiation suggesting phenotypic diversity in cervical precancerous lesions infected by single HPV.

Qualitative and Quantitative Diagnosis in Head and Neck Cancer.

The diagnosis is the art of determining the nature of a disease, and an accurate diagnosis is the true cornerstone on which rational treatment should be built. Within the workflow in the management of head and neck tumours, there are different types of diagnosis. The purpose of this work is to point out the differences and the aims of the different types of diagnoses and to highlight their importance in the management of patients with head and neck tumours. Qualitative diagnosis is performed by a pathologist and is essential in determining the management and can provide guidance on prognosis. The evolution of immunohistochemistry and molecular biology techniques has made it possible to obtain more precise diagnoses and to identify prognostic markers and precision factors. Quantitative diagnosis is made by the radiologist and consists of identifying a mass lesion and the estimation of the tumour volume and extent using imaging techniques, such as CT, MRI, and PET. The distinction between the two types of diagnosis is clear, as the methodology is different. The accurate establishment of both diagnoses plays an essential role in treatment planning. Getting the right diagnosis is a key aspect of health care, and it provides an explanation of a patient's health problem and informs subsequent decision. Deep learning and radiomics approaches hold promise for improving diagnosis.

The impact of the COVID-19 pandemic on organised cervical cancer screening: The first results of the Slovenian cervical screening programme and registry.

BACKGROUND: The COVID-19 pandemic threatens the impact of cervical cancer screening and global cervical cancer elimination goals. As cervical cancer screening programmes were adjusting to the new situation, we evaluated the intensity, quality, and outcomes of cervical cancer screening in Slovenia in the first seven months of the pandemic. METHODS: Historical observational study on data from a population-based cervical cancer screening registry. Number of cervical cytopathology (screening and follow-up), histopathology (diagnostic procedures, invasive procedures and number of newly diagnosed CIN2+ cases) and HPV test results from the entire Slovenian women population between January 1st and September 30th 2020 were compared to a three-year average of the years 2017-19. FINDINGS: A two-month screening lock-down between March 12th and May 8th 2020 resulted in an epidemic deficit of screening (-92%), follow-up (-70%), and HPV triage tests (-68%), as well as invasive diagnostic (-47%) and treatment (-15%) of cervical lesions. Time to diagnosis and treatment did not increase; times to laboratory results fluctuated but stayed within standards. Slovenia has entered the second epidemic intending to add as little as possible to the pandemic deficit of screening smears (-23%) and yearly CIN2+ cases (-10%). Women aged 30-39 were most affected, with the highest pandemic deficit of screening smears (-26%) and yearly CIN2+ cases (-19%). INTERPRETATION: The pandemic has deeply affected all levels of our lives. New vulnerable groups and inequalities have emerged that require recognition and action. To prevent long-term increases in the cervical cancer burden due to the COVID-19 pandemic, it is crucial that organised screening is maintained and monitored in settings where it can be safely and comprehensively provided. FUNDING: None.

Immunocytochemistry practices in European cytopathology laboratories-Review of European Federation of Cytology Societies (EFCS) online survey results with best practice recommendations.

BACKGROUND: Variability in preanalytical and analytical steps for immunocytochemistry (ICC) on cytology samples is poorly defined. The objective of this study was to evaluate current practices for ICC on cytology samples in European laboratories. METHODS: A link to an online survey with 19 questions about ICC practices was distributed to cytology laboratories through national representatives in the European Federation of Cytology Societies. RESULTS: In total, 245 laboratories responded to the survey by January 30, 2019. Cell blocks, cytospins, liquid-based cytology (LBC) preparations, and smears alone or in combination with other preparations were used for ICC in 38%, 22%, 21%, and 19% of laboratories, respectively. In general, various combinations of preparations were used for ICC in greater than one-half of laboratories (147 of 245; 60%), whereas only 1 specific type of cytology preparation was used in the remaining 98 of 245 laboratories (40%) laboratories. The majority of laboratories (217 of 226; 96%) performed ICC on automated platforms using protocols that were the same as those used for formalin-fixed, paraffin-embedded samples (238 of 527 laboratories; 45%), either optimized (138 of 527 laboratories; 26%) or optimized and validated (151 of 527 laboratories; 29%) for cytology preparations. Positive control slides, negative control slides, and external quality control were used in 174 of 223 (78%), 112 of 223 (50%), and 111 of 120 (50%) laboratories, respectively. Greater than 1000 ICC tests were performed yearly in 34% of laboratories (65 of 191; average, 1477 tests; median, 500 tests). CONCLUSIONS: ICC is extensively performed in European laboratories using variously prepared cytology preparations on automated platforms, mostly without quality-assurance measures.

Erythroblastic sarcoma presenting as a unilateral pleural effusion in a patient with myelodysplastic syndrome/myeloproliferative neoplasm-Case report with cytologic and histologic findings.

Erythroblastic sarcoma (ES) is an extremely rare extramedullary solid tumor of immature erythroid cells, with around a dozen human cases to our knowledge presented so far in the english literature, none of the cases presenting as pleural effusion. Here we describe a case of ES in a thoracic wall diagnosed by cytological examination of pleural effusion with histologic correlation in a 53-year-old patient with a 10-month history of myelodysplastic syndrome/myeloproliferative neoplasm with grade III reticulin myelofibrosis.

Histomorphologic assessment and distribution of high-risk human papillomavirus (HPV) types in cervical high-grade squamous intraepithelial lesions with unusual histomorphologic features.

In rare cases, equivocal histomorphology ('deceiving dysplasia') does not allow immediate diagnosis of cervical high-grade squamous intraepithelial lesion (HSIL). We studied whether these cases are correlated with specific high-risk human papillomavirus (hr HPV) types. During 2011-2017, 39 cases of p16-positive cervical tissue biopsies with unusual ('deceiving') dysplastic histomorphology were identified and matched with the same number of controls (typical HSIL samples). Histomorphological characteristics were reviewed blindly and HPV testing was performed using the clinically validated RealTime test (Abbott) and Anyplex HPV 28 (Seegene). HPV 16 and HPV 31 were the two most frequent HPV types in both groups, although minimum, proportional, hierarchical and any etiological attribution estimates for HPV 16 were significantly lower in the deceiving group (13.2%, 21.3%, 23.7% and 23.7%) than in the control group (32.4%, 48.1%, 48.6% and 48.6%). In addition, the distribution of other hr HPV types differed between the two study groups, with five HPV types (HPV 56, 58, 59, 73 and 82) detected only in the deceiving group. Histomorphologic review of both groups (regardless of HPV type) confirmed significant differences in nuclear atypia, maximum lesion thickness and cellularity, although these were diminished when cross-comparisons between HPV16/18 and non-HPV16/18 cases pooled from both study groups were evaluated. Different attribution estimates for HPV 16, HPV 16/18 and non-16/18 hr HPV types in deceiving and control groups were observed, in particular for HPV 16. However, an unusual (deceiving) histomorphology may also depend on unknown HPV-related molecular changes.

Use of vimentin immunocytochemical staining for evaluation of atypical cells in voided urine samples.

BACKGROUND: Cytomorphology of exfoliated atypical reactive/repair renal tubular cells (RRTC) can resemble atypical urothelial cells thus suggesting a differential diagnostic question of urothelial neoplasia in urinary cytology. Vimentin expression has been shown in RRTC and used for differentiation from atypical urothelial cells. METHODS: The institutional computer database was searched for urinary cytology cases with vimentin immunocytochemical staining (2008-2012). Original cytopathological diagnoses based on cytomorphology and the results of vimentin immunostaining were compared to follow-up data, including histopathological diagnosis, subsequent urinary cytopathology reports, and clinical findings. RESULTS: Of the 42 cases with vimentin immunocytochemical staining, 33 were positive and 9 negative. Consequently, significant renal disease was found in 9/33 (27%) of vimentin positive cases and nehrolithiasis in 4/33 (12%) of vimentin positive and 1/9 (11%) of vimentin negative cases. Erythrocyturia of undetermined origin was diagnosed in nine cases (seven vimentin positive and two negative). Urinary cytology follow-up was negative in three vimentin positive cases. Urothelial carcinoma was found in 3/9 (30%) of vimentin negative cases. Thirteen patients were lost to follow-up. CONCLUSIONS: Vimentin immunocytochemical staining could be used as an ancillary method for evaluation of atypical cells in urinary specimens in selected cases with RRTC exhibiting cytological atypia. Unnecessary diagnostic procedures for evaluation of urothelial carcinoma could be avoided in vimentin positive cases and further diagnostic work-up for evaluation of a significant renal disease could be suggested in vimentin positive cases. Diagn. Cytopathol. 2017;45:85-90. © 2016 Wiley Periodicals, Inc.

Symptoms and signs of ocular surface disease related to topical medication in patients with glaucoma.

PURPOSE: The aim of this study was to assess signs and symptoms of ocular surface disease (OSD) and the cytomorphological changes of ocular surface in glaucoma patients using preserved antiglaucoma drops. METHODS: In this cross-sectional study, 109 participants (79 patients with topical medication and 30 untreated controls) completed the Ocular Surface Diseases Index (OSDI) questionnaire and underwent an ophthalmic examination, including Schirmer test, tear film breakup time (TBUT), and fluorescein staining. Conjunctival specimens were collected by impression cytology and analyzed by light microscopy using Nelson's grading scheme (grades 0-3). This classification is based on the nucleus-to-cytoplasm ratios of epithelial cells and the numbers of goblet cells, with grade 2 considered abnormal. RESULTS: The medication group had significantly shorter TBUT (median [interquartile range]: 6.0 seconds [5.0-8.0 seconds] vs 9.5 seconds [6.0-12.3 seconds]; P<0.03), greater fluorescein staining (1.0 [0.75-1.25] vs 0 [0-0.25]; P<0.001), and higher impression cytology grade than the control group (median [range]: 1.0 [1:2 to 1:6] vs 0.6 [1:2 to 1:4]; P<0.001). The increasing number of drops instilled per day was associated with an increase in fluorescein staining (Spearman's rho r=0.475; P<0.001) and shorter TBUT (r=-0.278; P=0.014). The OSDI did not discriminate between the two groups. CONCLUSION: Clinical tests and impression cytology showed ocular surface damage in patients using preserved antiglaucoma medications. However, there was no statistically and clinically significant difference in symptoms measured by OSDI score between the medication and control groups.

Thyroid-like follicular carcinoma of the kidney in a patient with nephrolithiasis and polycystic kidney disease: a case report.

Thyroid-like follicular carcinoma of the kidney (TLFC), a rare neoplasm with low malignant potential, is histologically similar to primary thyroid follicular carcinoma, but characteristically lacks thyroid immunohistochemical markers. We report a case of 34-year old patient with nephrolithiasis. Ultrasound revealed hepatorenal cysts consistent with adult type polycystic kidney disease (ATPKD) and a cytologically confirmed left kidney tumor. Nephrectomy specimen contained sharply demarcated lesion of unusual morphology. Tubular and cystic structures lined by mostly cuboidal cells and filled with amorphous eosinophillic material, reminiscent of follicular carcinoma of the thyroid gland, were diagnostic for TLFC. Thyroid markers were negative. To our knowledge this is the first report of TFLC associated to ATPKD. Brief review of previously published TFLCs, possible relationship between entities and differential diagnosis are discussed. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/8067946569612694.

Image cytometric nuclear texture features in inoperable head and neck cancer: a pilot study.

BACKGROUND: Image cytometry can measure numerous nuclear features which could be considered a surrogate end-point marker of molecular genetic changes in a nucleus. The aim of the study was to analyze image cytometric nuclear features in paired samples of primary tumor and neck metastasis in patients with inoperable carcinoma of the head and neck. MATERIALS AND METHODS.: Image cytometric analysis of cell suspensions prepared from primary tumor tissue and fine needle aspiration biopsy cell samples of neck metastases from 21 patients treated with concomitant radiochemotherapy was performed. Nuclear features were correlated with clinical characteristics and response to therapy. RESULTS: Manifestation of distant metastases and new primaries was associated (p<0.05) with several chromatin characteristics from primary tumor cells, whereas the origin of index cancer and disease response in the neck was related to those in the cells from metastases. Many nuclear features of primary tumors and metastases correlated with the TNM stage. CONCLUSIONS: A specific pattern of correlation between well-established prognostic indicators and nuclear features of samples from primary tumors and those from neck metastases was observed. Image cytometric nuclear features represent a promising candidate marker for recognition of biologically different tumor subgroups.

Typing of renal tumors by morphological and immunocytochemical evaluation of fine needle aspirates.

Image-guided fine needle aspiration biopsy (FNAB) of renal masses can accurately evaluate malignancy. Adjunct methods are needed for accurate typing of renal cell carcinomas (RCC) and benign neoplasms. Cytopathological diagnoses of 79 routine ultrasound-guided FNAB of renal lesions were compared to consequent histological diagnosis and size of tumors. Cytology samples were sufficient for immunocytochemical subtyping in 43 cases (54.4%). The median tumor size was 2.8 cm, with 57 cases (76%) smaller than or equal to 4 cm. When a panel of immunocytochemical stainings (vimentin, CK7, CD117, P504S) was applied, accurate diagnoses were obtained in 11/12 (91.7%) of clear cell RCC (CRCC), 14/17 (82.3%) of papillary RCC (PRCC) and 5/7 (71.4%) of chromophobe RCC (ChRCC), respectively. Substantial cell pleomorphism with unusual immunostainings led to erroneous diagnosis of pheochromocytoma in CRCC with eosinophilic cytoplasm. Only 30% of CRCC were correctly diagnosed in the group without immunostaining, seven were suspicious for CRCC, and the remainder had unrepresentative material for CRCC. Cytopathological diagnoses were less accurate in oncocytomas (n=11), regardless of immunocytochemical staining. Cystic nephromas (n=2) and MEST (n=1) were overdiagnosed as suspicious and positive for PRCC, respectively, with immunocytochemical staining not assisting in correct diagnosis. RCC can be accurately typed as CRCC, PRCC or ChRCC in fine needle aspirates in a routine clinical setting if the cellular material is sufficient and a panel of antibodies is used (vimentin, CK7, P504S, CD117). The classification of oncocytomas and cystic nephromas is not reliable since atypical morphology and immunocytochemical reactions overlap with RCC.

Malignancy associated changes in epithelial cells of buccal mucosa: a potential cancer detection test.

OBJECTIVE: To analyze the presence of malignancy associated changes (MACs) in normal buccal mucosa cells of lung and breast cancer patients and their relationship to tumor subtype, stage and size. STUDY DESIGN: Buccal mucosa smears of 107 lung cancer and 100 breast cancer patients and corresponding healthy subjects were collected, stained by the DNA-specific Feulgen-thionin method and scanned using an automated high-resolution cytometer. Nuclear texture features of a minimum of 500 nuclei per slide were calculated, and statistical classifiers using Gaussian models of class-probability distribution were designed, trained and tested in 3 parts: (1) ability to separate cancer patient samples from controls, (2) cross-validation of classifiers for different cancer types, and (3) correlation of MAC expression with tumor subtype, stage and size. RESULTS: Lung and breast cancer induce MACs in normal buccal mucosa cells. The classifiers based on the selected nuclear features correctly recognized >80% of lung and breast cancer cases. The results indicate that MAC detection is not dependent on the tumor subtype, stage or size. CONCLUSION: The presence of MACs in buccal mucosa cells offers the potential for developing a new noninvasive cancer screening test.