Diagnostic interobserver agreement for thyroid fine-needle aspirates: Effects of reviewer experience and molecular diagnostics.

OBJECTIVES: Few cytologically indeterminate thyroid fine-needle aspirations (FNAs) harbor BRAF V600E. Here, we assess interobserver agreement for The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) category III (atypia of undetermined significance [AUS]) FNAs harboring BRAF V600E and contrast their features with those harboring non-BRAF V600E alterations, with attention to cytopathology experience. METHODS: Seven reviewers evaluated 5 AUS thyroid FNAs harboring BRAF V600E. To blind reviewers, cases were intermixed with 19 FNAs falling within other TBSRTC categories and in which genetic alterations other than BRAF V600E had been identified (24 FNAs total). Interobserver agreement against both "index" and most popular ("mode") diagnoses was calculated. Four additional BRAF V600E cases were independently reviewed. RESULTS: Reviewers included 3 trainees and 3 American Board of Pathology (board)-certified cytopathologists. Board-certified cytopathologists, whose experience ranged from 2 to more than 15 subspecialty practice years, had known AUS rates. BRAF V600E was identified in 5 of 260 (2%) AUS FNAs. Interobserver agreement was higher among cytopathologists with more experience. Mode diagnosis differed from index diagnosis in 6 of 11 cases harboring RAS-like alterations; mode diagnosis was AUS in 4 of 5 BRAF V600E FNAs. CONCLUSIONS: Atypia of undetermined significance of thyroid FNAs harboring BRAF V600E is uncommon yet relatively reproducible, particularly among pathologists with experience. It is advisable to sequence BRAF across V600 in such cases.

Navigating Practice Issues Related to the Unsatisfactory Cervicovaginal Papanicolaou Test: Survey Results of Laboratories Participating in the 2020 College of American Pathologists PAP Education Program.

CONTEXT.­: Unsatisfactory Papanicolaou (Pap) tests pose a unique set of challenges to the laboratory with regard to their processing, review, reporting, and performance of human papillomavirus (HPV) testing. There are no standardized guidelines for the review process and handling of unsatisfactory Pap tests. OBJECTIVE.­: To assess the current practice patterns regarding various aspects of the unsatisfactory Pap test, from processing to reporting, across laboratories worldwide. DESIGN.­: A supplemental questionnaire was mailed to laboratories participating in the 2020 College of American Pathologists (CAP) Gynecologic Cytopathology (PAP Education) Program, requesting data regarding the unsatisfactory Pap test. RESULTS.­: Of 1520 participating laboratories, 619 (40.7%) responded, and the responses of 577 laboratories were included for further analysis. Only 64.6% (373 of 577) laboratories used the unsatisfactory Pap test criteria as specified by the 2014 Bethesda System. About three-quarters of the respondents (433 of 576; 75.2%) routinely rescreened unsatisfactory Pap tests. Routine repreparation of such Pap tests was performed by 54.9% (316 of 576) of laboratories, and 52.0% (293 of 563) used glacial acetic acid for repreparing excessively bloody specimens. HPV test results were reported for unsatisfactory Pap tests, always or sometimes, by 62.4% (353 of 566) of respondents. CONCLUSIONS.­: This CAP survey reveals important information regarding the practice patterns pertaining to several aspects of the unsatisfactory Pap test. It also provides valuable insight into the quality assurance measures that can be implemented for such tests. Future studies can further aid in the standardization of all components of the handling of unsatisfactory Pap tests for overall quality improvement.

Optimal carcinoembryonic antigen (CEA) cutoff values in the diagnosis of neoplastic mucinous pancreatic cysts differ among assays.

AIM: Pancreatic cyst fluid carcinoembryonic antigen (CEA) is a pivotal test in the diagnosis and management of neoplastic mucinous cysts (NMC) of the pancreas. Cyst fluid CEA levels of 192 ng/mL have been widely used to identify NMC. However, CEA values are unique to and significantly differ between individual assays with various optimal cutoffs reported in the literature for NMC. Here, we investigate the optimal CEA cut-off value of pancreatic cysts from two different assays to identify differences in thresholds. METHODS: Pancreatic cyst fluid CEA levels, CEA assay platform (Beckman Dxl (BD) or Siemens Centaur XP (SC)), and clinical/pathological information were retrospectively collected. Cases were categorised into either NMC or non-NMC. Optimal CEA cut-off values were calculated via a receiver operator characteristic curve. Cut-off values were then identified separately by assay platform. RESULTS: In total, 149 pancreatic cystic lesions with concurrent CEA values (SC: n=47; BD: n=102) were included. Histological correlation was available for 26 (17%) samples. The optimal CEA cut-off value for all samples at the study institution was 45.9 ng/mL (area under the curve (AUC)=86, Sn=85.7%, Sp=73.8%). When analysed separately by CEA assay, the cut-off values were 45.9 ng/mL (AUC=84.27, Sn=89.7%, Sp=71.4%) for BD and 24.4 ng/mL (AUC=77, Sn=81.8%, Sp=75%) for SC (p=0.48). CONCLUSIONS: This study showed an optimal pancreas cyst CEA cut-off threshold of 45.9 ng/mL, which is lower than commonly cited literature with different cutoffs on the two separate platforms (BD: 45.9 ng/mL, SC: 24.4 ng/mL).

Pancreaticobiliary Cytology Practice in 2021: Results of a College of American Pathologists Survey.

CONTEXT.­: The College of American Pathologists (CAP) surveys provide national benchmarks of pathology practice. OBJECTIVE.­: To investigate pancreaticobiliary cytology practice in domestic and international laboratories in 2021. DESIGN.­: We analyzed data from the CAP Pancreaticobiliary Cytology Practice Supplemental Questionnaire that was distributed to laboratories participating in the 2021 CAP Nongynecologic Cytopathology Education Program. RESULTS.­: Ninety-three percent (567 of 612) of respondent laboratories routinely evaluated pancreaticobiliary cytology specimens. Biliary brushing (85%) was the most common pancreaticobiliary cytology specimen evaluated, followed by pancreatic fine-needle aspiration (79%). The most used sampling methods reported by 235 laboratories were 22-gauge needle for fine-needle aspiration (62%) and SharkCore needle for fine-needle biopsy (27%). Cell block was the most used slide preparation method (76%), followed by liquid-based cytology (59%) for pancreatic cystic lesions. Up to 95% (303 of 320) of laboratories performed rapid on-site evaluation (ROSE) on pancreatic solid lesions, while 56% (180 of 320) performed ROSE for cystic lesions. Thirty-six percent (193 of 530) of laboratories used the Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology in 2021. Among all institution types, significant differences in specimen volume, specimen type, ROSE practice, and case sign-out were identified. Additionally, significant differences in specimen type, slide preparation, and ROSE practice were found. CONCLUSIONS.­: This is the first survey from the CAP to investigate pancreaticobiliary cytology practice. The findings reveal significant differences among institution types and between domestic and international laboratories. These data provide a baseline for future studies in a variety of practice settings.

The Implementation of Nongynecologic Reporting Systems in Cytopathology Laboratories Is Highly Variable: Analysis of Data From a 2020 Supplemental Survey of Participants in the College of American Pathologists Interlaboratory Comparison Program in Nongynecologic Cytology.

CONTEXT­: In recent years, several reporting systems have been developed by national and international cytopathology organizations to standardize the evaluation of specific cytopathology specimen types. OBJECTIVE­: To assess the current implementation rates, implementation methods, and barriers to implementation of commonly used nongynecologic reporting systems in cytopathology laboratories. DESIGN­: Data were analyzed from a survey developed by the committee and distributed to participants in the College of American Pathologists Nongynecologic Cytopathology Education Program mailing. RESULTS­: Nongynecologic reporting systems with the highest rate of adoption were the Bethesda System for Reporting Thyroid Cytopathology, 2nd edition (74.1%; 552 of 745); the Paris System for Reporting Urinary Cytology (53.9%; 397 of 736); and the Milan System for Reporting Salivary Gland Cytopathology (29.1%; 200 of 688). The most common reason given for not adopting a reporting system was satisfaction with a laboratory's current system. Implementation varied among laboratories with regard to which stakeholders were involved in deciding to implement a system and the amount of education provided during the implementation process. CONCLUSIONS­: The implementation of nongynecologic reporting systems in cytopathology laboratories was highly variable.

Role of Fine Needle Aspiration Cytology in the Diagnosis of Gynecologic Tumors.

BACKGROUND: The tumors involving the gynecologic tract encompass a wide range of lesions including those of epithelial, mesenchymal, sex cord-stromal, and germ cell origin. Amongst the carcinomas of tubo-ovarian origin, high-grade serous carcinoma is the most common malignancy. The primary role of fine needle aspiration (FNA) cytology in the management of gynecologic tract malignancies is in the diagnosis of their recurrences/metastases. In patients presenting with advanced disease, the cytology specimen may be the initial or the only sampling performed before the initiation of treatment. SUMMARY: This review will discuss the cytologic findings of various gynecologic tract neoplasms with regard to their morphologic features, differential diagnoses, and the ancillary studies that can assist in their recognition. KEY MESSAGES: FNA cytology serves as a valuable tool in the diagnosis and management of gynecologic tract malignancies. However, making an accurate diagnosis of these entities, especially on limited cytology specimens, can be challenging. Awareness regarding the morphologic spectrum of these tumors, their potential mimics, and the ancillary studies that can be employed to refine their characterization, can assist in arriving at the correct diagnosis.

Diagnostic implication of extracellular mucin in pancreatic/biliary brushing and stent cytology.

BACKGROUND: Pancreatic and/or biliary (PB) brushing is commonly used to rule out malignant strictures. Many studies have attempted to characterize cytomorphologic characteristics of brushing and stent cytology. However, scant literature exists on the diagnostic implication (DI) of thick extracellular mucin (ECM) indicative of neoplasm in these samples. This study was aimed at reviewing the DI of thick ECM in PB brushing and stent cytology. METHODS: A retrospective search of consecutive cytologic samples of PB brushings/stents with corresponding surgical pathology or relevant clinical information over a 1-year period was performed. Blinded review of the slides was performed by two cytopathologists. The slides were assessed for the presence, quantity, and quality of ECM. The results were analyzed for statistical significance with the Fisher exact and χ2 tests. RESULTS: One hundred ten cases were identified from 63 patients. Twenty-two cases (20%) were PB brushings only without a prior stent. The remaining 88 cases (80%) had a preexisting stent for symptomatic obstruction. Fourteen of 22 cases (63%) without prior stents and 67 of 88 poststented cases (76%) were nonneoplastic (NN) upon follow-up. ECM was present more frequently in neoplastic cases than in NN cases (p = .03). Among NN cases (n = 87), poststented samples showed more evidence of ECM than prestented samples (15% vs. 45%, p = .045). Identical thick ECM was observed in NN poststent and main-duct intraductal papillary neoplasm samples. CONCLUSIONS: Although ECM was frequently seen in neoplastic cases, NN cases showed increased evidence of thick ECM among poststented samples. Thick ECM may be common in stent cytology, regardless of the underlying biologic process.

Significant outcomes associated with high-risk human papillomavirus negative Papanicolaou tests.

INTRODUCTION: The 2020 American Cancer Society guidelines preferred primary human papillomavirus (HPV) screening for cervical cancer prevention. Studies investigating the role of cytology in detection of cervical precancer/cancer have focused on high-grade squamous intraepithelial lesion (HSIL) or worse interpretations. Here, we have examined the significance of all those cytology results that require histologic follow-up as per the current management guidelines, regardless of the HPV test result. MATERIALS AND METHODS: A database search (September 2010 to December 2019) retrieved cervical Papanicolaou tests with any of the following interpretations: ≥ atypical squamous cells - cannot exclude HSIL or low-grade squamous intraepithelial lesion, HSIL cannot be excluded, and ≥ atypical glandular cells, not otherwise specified and its subcategories. Of these, those with concurrent negative HPV test result were included for further analysis. For this cohort, relevant clinical history and histologic follow-up (within 1 year) were recorded. RESULTS: The study cohort comprised 763 patients. Of them, 586 (76.8%) patients had histologic follow-up: 53 (9.0%) had ≥ HSIL/adenocarcinoma in situ; of which, 43 (81.1%) had prior abnormal cytology/histology/not otherwise specified history and/or HPV positivity, and 66 (11.3%) had HPV-unassociated neoplasia; of which, 60 (90.9%) had a known diagnosis or clinical signs/symptoms of the disease. CONCLUSION: With widespread adoption of risk-based approach to management, the role of cytology, by itself, will likely diminish in the detection of HPV-associated lesions. Additional data regarding the role of cytology in the screening of patients with no/unknown/limited history and in the detection/management of HPV-independent lesions may be helpful for designing future screening guidelines.

Diagnostic features of low- and high-grade mucinous neoplasms in pancreatic cyst FNA cytology.

BACKGROUND: Pancreatic cyst cytology evaluates for neoplastic mucin and epithelial grade. This study describes cytological features of low- and high-grade mucinous neoplasms (MNs) using gastrointestinal contaminants for comparison. METHODS: Histologically confirmed pancreatic cystic neoplasms were reviewed by a panel of cytopathologists to identify which, among 26 selected cytologic features, correlate significantly with low- and high-grade MN. A test for greater than or equal to four of eight high-grade features (three-dimensional architecture, high nuclear:cytoplasmic ratio, moderate nuclear membrane abnormalities, loss of nuclear polarity, hyperchromasia, >4:1 nuclear size variation in one cluster, karyorrhexis, and necrosis) was assessed for identifying a high-grade neoplasms. Additional characteristics of the cohort such as cyst fluid carcinoembryonic antigen results, molecular testing, Papanicolaou Society of Cytopathology classification, and select high-risk clinical features are described. RESULTS: Endoscopic ultrasound fine-needle aspirations from 134 MN and 17 serous cystadenomas containing gastrointestinal contaminants were included. The MN consisted of 112 (84%) intraductal papillary MNs (low-grade = 69, 62%; high-grade = 24, 21%; and invasive = 19, 17%) and mucinous cystic neoplasms (low-grade = 20, 90%; high-grade = 2, 10%). Half had greater than five clusters of epithelium for analysis. Compared with gastrointestinal contaminants, mucin from MN was thick and colloid-like (40% vs. 6%, p < .01), covered >20% of the smear area (32% vs. none, p < .01), and contained histiocytes (46% vs. 18%, p = .04). Greater than or equal to four of eight select high-grade features was present in 36% of high-grade MN with sensitivity 37% and 98% specificity. CONCLUSION: Colloid-like features, >20% of smear, and histiocytes correlated with MN. Testing for greater than or equal to four high-grade features had low sensitivity and high specificity for high-grade MN.

Evaluating the role of Z-stack to improve the morphologic evaluation of urine cytology whole slide images for high-grade urothelial carcinoma: Results and review of a pilot study.

BACKGROUND: Whole slide imaging (WSI) adoption has been slower in cytopathology due, in part, to challenges in multifocal plane scanning on 3-dimensional cell clusters. ThinPrep and other liquid-based preparations may alleviate the issue by reducing clusters in a concentrated area. This study investigates the use of Z-stacked images for diagnostic assessment and the experience of evaluating urine ThinPrep WSI. METHODS: Thirty ThinPrep urine cases of high-grade urothelial carcinoma (n = 22) and cases of negative for high-grade urothelial carcinoma (n = 8) were included. Slides were scanned at 40× magnification without Z-stack and with Z-stack at 3 layers, 1 µm each. Six cytopathologists and 1 cytotechnologist evaluated the cases in 2 rounds with a 2-week wash-out period in a blinded manner. A Cohen's Kappa (CK) calculated concordance rates. A survey after each round evaluated participant experience. RESULTS: CK with the original report ranged from 0.606 to 1.0 (P < .05) without Z-stack and 0.533 to 1.0 (P < .05) with Z-stack both indicating substantial-to-perfect concordance. For both rounds, interobserver CK was moderate-to-perfect (0.417-1.0, P < .05). Intraobserver CK was 0.697-1.0 (P < 0.05), indicating substantial to perfect concordance. The average scan time and file size for slides without Z-stack and with Z-stack are 6.27 minute/0.827 GB and 14.06 minute/2.650 GB, respectively. Surveys demonstrated a range in comfort and use with slightly more favorable opinions for Z-stacked cases. CONCLUSIONS: Z-stack images provide minimal diagnostic benefit for urine ThinPrep WSI. In addition, Z-stacked urine WSI does not justify the prolonged scan times and larger storage needs compared to those without Z-stack.

Combining molecular testing and the Bethesda category III:VI ratio for thyroid fine-needle aspirates: A quality-assurance metric for evaluating diagnostic performance in a cytopathology laboratory.

BACKGROUND: Molecular testing (MT) of thyroid fine-needle aspiration (FNA)-derived genetic material is commonly used to assess malignancy risk for indeterminate cases. The Bethesda System for Reporting Thyroid Cytopathology (TBS) provides limited guidance for the appropriate use of category III (atypia of undetermined significance [AUS]). The authors combined MT with cytomorphology to monitor AUS diagnoses in a cytopathology laboratory. METHODS: Neoplasia-associated genetic alterations (NGAs) were determined by MT of preoperative FNA biopsies or resected malignancies and were categorized as BRAF V600E mutations, RAS-like mutations (HRAS, NRAS, or KRAS mutations or non-V600E BRAF mutations), or other mutations. RESULTS: Among 7382 thyroid FNA biopsies, the AUS rate was 9.3% overall and ranged from 4.3% to 24.2% among 6 cytopathologists (CPs) who evaluated >150 cases. The ratio of specimens falling into TBS category III to specimens falling into category VI (malignant) (the III:VI ratio) was 2.4 overall (range, 1.1-8.1), and the ratio of specimens falling into TBS categories III and IV (follicular neoplasm or suspicious for follicular neoplasm) combined (III+IV) to specimens falling into category VI (the [III+IV]:VI ratio) was 2.9 overall (range, 1.4-9.5). MT was performed on 588 cases from 560 patients (79% women) with a median age of 56 years (range, 8-89 years). BRAF V600E mutation was the most common (76% of cases) in TBS category VI and was rare (3%) in category III. RAS-like mutations were most common in TBS categories III (13%), IV (25%), and V (suspicious for malignancy) (17.5%). The NGA rate in AUS cases fell between 5% and 20% for 5 of 6 CPs and did not correlate with the III:VI ratio or the (III+IV):VI ratio. CONCLUSIONS: Lack of correlation between the NGA rate and easily calculable diagnostic ratios enables the calibration of diagnostic thresholds, even for CPs who have normal metrics. Specifically, calculation of the NGA rate and the III:VI ratio may allow individual CPs to determine whether they are overcalling or undercalling cases that other CPs might otherwise recategorize.

Rescreening Practices of Negative Papanicolaou Tests With Positive Human Papillomavirus Test Result.

CONTEXT.­: The yield of the prospective rescreening process for "negative for intraepithelial lesion or malignancy" (NILM) Papanicolaou (Pap) tests is higher with the inclusion of a greater proportion of high-risk cases. One of the suggested criteria for classifying a Pap test finding as high risk is recent or concurrent high-risk human papillomavirus (HPV) positivity. OBJECTIVE.­: To evaluate how the results of HPV testing have been incorporated in the prospective rescreening of NILM Pap tests across a wide range of laboratories. DESIGN.­: A questionnaire survey was sent to laboratories participating in the 2019 College of American Pathologists (CAP) Gynecologic Cytology (PAP Education) Program. RESULTS.­: Of the 1507 participating laboratories, 667 (44%) responded to the survey. Most laboratories (59.4%; 396 of 667) had not incorporated HPV test/genotyping results to select NILM Pap tests for rescreening. Amongst the remaining laboratories, for NILM HPV-positive Pap test results, 112 (16.8%) had a policy to rescreen by a cytotechnologist only, 51 (7.6%) by a pathologist only, and 86 (12.9%) by both. Of 264 laboratories, 181 (68.6%) reported the cytology upon availability of the HPV test result and completion of the secondary review. Of 661 laboratories, 145 (21.9%) included consensus-type recommendations in the cytology report for such Pap tests. CONCLUSIONS.­: This CAP survey provides significant information regarding the current trends in the use of HPV test results in prospective rescreening of NILM Pap tests. Future studies on quality improvement can further assist in the standardization of this process across different laboratories.

Underrecognized Patterns of High-Grade Squamous Intraepithelial Lesion on ThinPrep Preparations.

OBJECTIVES: To identify less readily identifiable patterns of high-grade squamous intraepithelial lesions (HSIL) in negative human papillomavirus (HPV)-positive Papanicolaou (Pap) tests on ThinPrep preparations. METHODS: Of all HPV-positive Pap tests that were negative for intraepithelial lesion or malignancy (NILM) from July 2013 to June 2018, those with HSIL on subsequent histology within 6 months were identified. ThinPrep slides from the latter group (group 1) and from NILM HPV-negative Pap tests with negative follow-up (group 2) were reviewed independently by 4 participants. Group 1 cases were then reviewed together for consensus and with the ThinPrep Imaging System (TIS). Any discrepancies from the original interpretation were recorded. RESULTS: The study cohort included 57 cases each in groups 1 and 2. On final review of group 1 cases, 17 (29.8%) were classified as NILM or unsatisfactory. Of the remaining, 4 cases revealed rare abnormal cells not flagged by the TIS in the fields of view. In the 36 cases (63.1%) with screening or interpretative errors, the key cytologic findings accounting for major discrepancies included atypical metaplastic cells, atypical repair, rare syncytial groups, and atypical immature metaplastic cells. CONCLUSIONS: There are 3 main underrecognized patterns of HSIL in cervical cytology: atypical metaplastic cells, atypical repair, and rare syncytial groups.

The interpretation of high-grade squamous intraepithelial lesion on anal cytology: a comparative analysis with the cervical Papanicolaou test.

INTRODUCTION: Prior studies have shown that high-grade squamous intraepithelial lesion (HSIL) tends to be underdiagnosed on anal cytology. Our study aims to decipher the interpretative challenges of HSIL that are more specific to anal cytology specimens by comparing them to cervical Papanicolaou tests. MATERIALS AND METHODS: One hundred cases each of anal and cervical cytology specimens with HSIL interpretation and concordant histologic follow-up were retrieved and diagnostically confirmed. Patient demographic data were obtained from the electronic medical record. The cytologic specimens were reviewed and statistically compared in terms of proportion of HSIL cells, HSIL patterns and types, and cytoplasmic area of HSIL cells (with digital image analysis). A P value of <0.05 was considered statistically significant. RESULTS: Of the patients with anal HSIL, 97% were human immunodeficiency virus-positive and 60% were men who have sex with men. The anal cytology specimens significantly differed from the cervical ones in several respects: proportion of HSIL cells, cytoplasmic area of HSIL cells, cases with HSIL cells in syncytial groups (10 versus 57) and cases with keratinizing HSIL (45 versus 10). The P value was <0.0001 for all comparisons except for the proportion of HSIL cells (P = 0.001). CONCLUSIONS: Anal cytologic HSIL, in contrast to its cervical counterpart, exhibits fewer abnormal cells and smaller size of the diagnostic cells with a higher percentage of keratinizing lesions. A careful scrutiny of the sample with an enhanced understanding of the morphology and better sampling may help improve the detection of anal HSIL on cytology.

Interobserver variability between cytopathologists and cytotechnologists upon application and characterization of the indeterminate category in the Milan System for Reporting Salivary Gland Cytopathology.

BACKGROUND: The indeterminate categories in the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) are diagnostically challenging because of inherent heterogeneity and complexity, with wide interobserver variability (IOV). Herein, the authors explore the concordance rate (CR) between cytopathologists (CPs) and cytotechnologists (CTs) in interpreting indeterminate salivary gland lesions using the MSRSGC. METHODS: Between 2011 and 2016, 86 indeterminate fine-needle aspirations had slides available for review, of which 48 had follow-up. Four CPs and 2 CTs performed an independent, blinded review of these slides and categorized them according to the MSRSGC. The CRs between CTs and CPs with the final sign-out cytopathologist (FCP) were assessed, and interobserver agreement was categorized into uniform, majority, divided, minimal, or no agreement. RESULTS: The overall CR with the FCP ranged from 48.8% to 60.5% for CPs and from 22.1% to 36% for CTs. IOV κ scores for the entire group were 0.314 and, with the FCP as the reference, ranged from 0.403 to 0.539 for CPs and from 0.091 to 0.254 for CTs. Uniform, majority, divided, minimal, and no agreement was noted in 12.8%, 31.4%, 38.4%, 10.5%, and 6.9%, respectively, of all cases and in 16.7%, 35.4%, 31.3%, 8.3%, and 6.3%, respectively, of the cases with follow-up. Diagnostic challenges included distinguishing lymphoma from a reactive process and distinguishing mucin from mucin-like material. CONCLUSIONS: CPs had modestly higher CRs compared with CTs; and, although the variable CRs highlight indeterminate IOV, the MSRSGC enables reproducibility. Characterizing larger cohorts in the indeterminate categories will further improve MSRSGC criteria. Moreover, education on the MSRSGC should include CTs and CPs to improve overall diagnostic accuracy.

Effects of Implementing the Dual Papanicolaou Test Interpretation of ASC-H and LSIL Following Bethesda 2014.

OBJECTIVES: To evaluate the impact of implementing the dual interpretation of atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H) and low-grade squamous intraepithelial lesion (LSIL) after the Bethesda System 2014 and to compare it with other indeterminate interpretations. METHODS: Rates of high-risk human papillomavirus (HPV) positivity and histologic follow-up and the proportion of women with high-grade squamous intraepithelial lesion on histologic follow-up were compared for the combined interpretation of ASC-H and LSIL (ASCHL) and the categories of LSIL, cannot exclude high-grade squamous intraepithelial lesion (LSIL-H) and ASC-H. RESULTS: The percentage of ASCHL HPV-positive cases (86.0%) was similar to that of LSIL-H but significantly higher in comparison to that of ASC-H. The rates of cervical intraepithelial neoplasia grade 2 or higher (CIN 2+) and CIN 3+ for ASCHL (29.6% and 3.6%, respectively) were similar to those of LSIL-H and ASC-H. When stratified by HPV test results, the proportions of patients with CIN 2+ and CIN 3+ remained statistically similar to those with ASCHL and with LSIL-H and ASC-H. CONCLUSIONS: Considering the similar risks of CIN 2+ and CIN 3+ for ASCHL and ASC-H, having a separate category of ASCHL for reporting cervical cytology appears to be redundant.

Is hysterectomy necessary for the treatment of preinvasive stratified mucin producing intraepithelial lesions of the cervix?

OBJECTIVES: Stratified mucin producing intraepithelial lesion (SMILE) is an uncommon premalignant cervical intraepithelial lesion, characterized by histopathologic features resembling those observed in high grade squamous intraepithelial lesions and adenocarcinoma in situ of the cervix. Its hybrid morphology poses a pathologic challenge with no specific management guidelines. The goal of this study was to review the natural history of SMILE and treatment based outcomes. METHODS: A retrospective pathology review of all cases of cervical intraepithelial lesions, with confirmation of all SMILE lesions, at one institution between 2007 and 2019, was performed. Clinical and pathologic characteristics, management options, and patient outcomes were reviewed and analyzed. Inclusion criteria included all patients diagnosed initially with SMILE on biopsy, excisional procedure, or simple hysterectomy. Patients diagnosed with SMILE had to fulfill the following pathologic features: stratified columnar epithelium with nuclear atypia and mucin production throughout the epithelial thickness with increased mitotic activity, and/or apoptotic bodies. Pathologic slides were re-evaluated by a pathologist to confirm the diagnosis and review margin status. RESULTS: 24 patients with SMILE were identified. Mean age at diagnosis was 36.2 years (range 25-53) with 67% (16/24) diagnosed before the age of 40. The majority (54%, 13/24) were nulliparous and 63% (15/24) had a past history of abnormal Pap smears. 92% (22/24) of patients were positive for high risk human papillomavirus, with 13% (n=3) presenting with a normal Pap smear. Diagnosis was made primarily on colposcopy (n=16), cold knife cone/loop electrosurgical excision procedure (n=7), or hysterectomy (n=1). Most patients (71%, 17/24) had a co-existing precancerous lesion at the time of diagnosis and the most common was high grade squamous intraepithelial lesion (53%). Five invasive lesions were also identified at the time of diagnosis of SMILE (2 adenocarcinoma, 3 adenosquamous), 1 of which underwent chemoradiation. Among all patients, 25% (6/24) underwent hysterectomy (4 simple, 2 radical), while 63% (17/24) of patients underwent a fertility sparing excisional procedure; 4% (1/24) were incidentally diagnosed on hysterectomy. 18 patients had negative margins and 2 patients had positive margins. Over a median follow-up of 29 months (range 3-105), all of the fertility sparing patients with negative margins had no recurrence. Among the two patients with positive margins, one had no recurrence on repeat excision and the other underwent repeat excision with persistent SMILE identified, subsequent negative margin, and no recurrence since. DISCUSSION: Our data showed that most patients with SMILE were young, positive for high risk human papillomavirus, nulliparous, and presented with coexisting lesions. Excisional procedures with negative margins may be sufficient fertility sparing treatment in patients with preinvasive SMILE with a low risk of recurrence. There should be consideration of hysterectomy at the completion of childbearing.

Endoscopic ultrasound-guided tissue acquisition of solid mass lesions of the pancreas: A retrospective comparison study of fine-needle aspiration and fine-needle biopsy.

BACKGROUND: Although endoscopic ultrasound guided fine-needle biopsy (EUS-FNB) has emerged as an alternative to fine-needle aspiration (FNA) for the sampling of solid pancreatic mass lesions, it remains unclear which method is more effective. We compared the diagnostic yields of FNA, FNB, and combined FNA/FNB at a tertiary care institution. METHODS: Specimens from EUS-FNA (04/2014-08/2017) and EUS-FNB (10/2015-08/2017) with SharkCore needle of pancreatic solid mass lesions were retrieved. Clinical, radiologic, and pathologic data was recorded. Pathology results of malignancy/neoplasms with uncertain malignant potential were considered as true positive. The "negative" cases included were with ≥6 months of follow-up. Nondiagnostic cases showed unremarkable pancreatic tissue, nonpancreatic elements, atypia, or features suspicious for malignancy. Diagnostic yield was defined as percentage of lesions sampled in which a benign or malignant tissue diagnosis, as defined above, was obtained. Statistical comparisons were performed using Fisher's exact test and univariable and multivariable logistic regression analysis. RESULTS: The study cohort included 76 FNA only cases, 88 FNB only cases, and 40 combined FNA/FNB cases. Diagnostic yields were 70% (FNA), 70% (FNB), and 83% (FNA/FNB), which were not statistically different. Increase in lesion size and presence of ROSE were significantly associated with a diagnostic outcome on both univariable and multivariable analysis, unlike the number of passes. CONCLUSION: Our results demonstrate that for solid pancreatic lesions, the diagnostic yields of FNA, FNB, and combined FNA and FNB are comparable. Presence of ROSE and increasing lesion size increased the diagnostic yield while the number of passes had no significant impact.

Insulinoma-associated protein 1 (INSM1) is a robust marker for identifying and grading pancreatic neuroendocrine tumors.

BACKGROUND: Pancreatic neuroendocrine tumor (PNET) is a diagnostic challenge with limited samples in not only identification but grading. Prior studies have shown insulinoma-associated protein 1 (INSM1) to be a robust marker in identifying PNETs from other solid pancreatic tumors on resection specimens. In this study, we investigated the utility of INSM1 not only for identifying PNETs but also for grading in cell blocks (CBs) and surgical resections (SRs). METHODS: A search for PNET cases between 2000 and 2019 identified 55 samples (26 CBs and 29 SRs) that were further separated into high (2 CBs, 3 SRs), intermediate (4 CBs, 7 SRs), and low (20 CBs, 19 SRs) grades based on their final pathology report and Ki-67 level. Immunohistochemical (IHC) staining for INSM1 (C-8, Santa Cruz Biotechnology [1:100]) was performed and quantified using an H score of 0 to 300. Non-PNET solid pancreatic tumors were compared and included acinar cell carcinoma, solid pseudopapillary neoplasm, and ductal adenocarcinoma. RESULTS: All 55 cases of PNET demonstrated nuclear INSM1 staining. The average H scores for INSM1 staining of PNET were 254 and 252 in CB and SR, respectively. The H scores decreased with increasing tumor grade, with low-grade (G1), intermediate-grade (G2), and high-grade (G3) tumors showing average INSM1 H scores of 229 and 253, 266 and 253, and 30 and 33 in both CB and SR, respectively. CONCLUSION: IHC with INSM1 plays a role in identifying and potentially grading PNETs.