Endoscopic ultrasound (EUS)-guided fine needle biopsy alone vs. EUS-guided fine needle aspiration with rapid onsite evaluation in pancreatic lesions: a multicenter randomized trial.

BACKGROUND: Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the standard in the diagnosis of solid pancreatic lesions, in particular when combined with rapid onsite evaluation of cytopathology (ROSE). More recently, a fork-tip needle for core biopsy (FNB) has been shown to be associated with excellent diagnostic yield. EUS-FNB alone has however not been compared with EUS-FNA + ROSE in a large clinical trial. Our aim was to compare EUS-FNB alone to EUS-FNA + ROSE in solid pancreatic lesions. METHODS: A multicenter, non-inferiority, randomized controlled trial involving seven centers was performed. Solid pancreatic lesions referred for EUS were considered for inclusion. The primary end point was diagnostic accuracy. Secondary end points included sensitivity/specificity, mean number of needle passes, and cost. RESULTS: 235 patients were randomized: 115 EUS-FNB alone and 120 EUS-FNA + ROSE. Overall, 217 patients had malignant histology. The diagnostic accuracy for malignancy of EUS-FNB alone was non-inferior to EUS-FNA + ROSE at 92.2 % (95 %CI 86.6 %-96.9 %) and 93.3 % (95 %CI 88.8 %-97.9 %), respectively (P = 0.72). Diagnostic sensitivity for malignancy was 92.5 % (95 %CI 85.7 %-96.7 %) for EUS-FNB alone vs. 96.5 % (93.0 %-98.6 %) for EUS-FNA + ROSE (P = 0.46), while specificity was 100 % in both. Adequate histological yield was obtained in 87.5 % of the EUS-FNB samples. The mean (SD) number of needle passes and procedure time favored EUS-FNB alone (2.3 [0.6] passes vs. 3.0 [1.1] passes [P < 0.001]; and 19.3 [8.0] vs. 22.7 [10.8] minutes [P = 0.008]). EUS-FNB alone cost on average 45 US dollars more than EUS-FNA + ROSE. CONCLUSION: EUS-FNB alone is non-inferior to EUS-FNA + ROSE and is associated with fewer needle passes, shorter procedure time, and excellent histological yield at comparable cost.

Immunocytochemistry for diagnostic cytopathology-A practical guide.

Cytological specimens, which are obtained by minimally invasive methods, are an excellent source of diagnostic material. Sometimes they are the only material available for diagnosis as well as for prognostic/predictive markers. When cytomorphology is not straightforward, ancillary tests may be required for a definitive diagnosis to guide clinical management. Immunocytochemistry (ICC) is the most common and practical ancillary tool used to reach a diagnosis when cytomorphology is equivocal, to differentiate entities with overlapping morphological features, and to determine the cell lineage and the site of origin of a metastatic neoplasm. Numerous immunomarkers are available, and some are expressed in multiple neoplasms. To rule out entities within a differential diagnosis, the use of more than one marker, sometimes panels, is necessary. ICC panels for diagnostic purposes should be customised based on the clinical context and cytomorphology, and the markers should be used judiciously to preserve material for additional tests for targeted therapies in the appropriate setting. This review offers a practical guide for the use of ICC for diagnostic cytopathology, covering the most commonly encountered non-hematolymphoid diagnostic scenarios in various body sites.

The EVVA Cohort Study: Anal and Cervical Type-Specific Human Papillomavirus Prevalence, Persistence, and Cytologic Findings in Women Living With HIV.

Background: The risk of anal cancer due to high-risk human papillomavirus (HR-HPV) is higher in women living with human immunodeficiency virus (HIV) than in the general population. We present findings of cervical and anal HPV and cytologic tests at baseline in the EVVA cohort study and HPV persistence data 6 months after baseline. Methods: Semiannual visits included questionnaires, chart reviews, cervical/anal cytologic and cervical/anal HPV testing for 2 years. Genotyping for 36 HPV genotypes was performed using the Roche Linear Array HPV genotyping test. Results: A total of 151 women living with HIV were recruited. At baseline, 75% had anal HPV, 51% had anal HR-HPV, 50% had cervical HPV, and 29% had cervical HR-HPV. Anal HPV-16 and HPV-51 were more frequent in women born in Canada (31% and 29%, respectively, compared with ≤16% for other women). Most anal HR-HPV types detected at 6 months (57%-93%) were persistent from baseline. Findings of anal cytologic tests were abnormal for 37% of women. Conclusions: Anal HPV is highly prevalent in women living with HIV, and type distribution varies by place of birth. High-resolution anoscopy was indicated in more than one third of results. As anal cancer is potentially preventable, these important findings need to be considered when selecting the best approach for anal cancer screening programs.

Can the tall cell variant of papillary thyroid carcinoma be distinguished from the conventional type in fine needle aspirates? A cytomorphologic study with assessment of diagnostic accuracy.

OBJECTIVES: The tall cell variant of papillary thyroid carcinoma (TCV-PTC) is an aggressive variant of PTC requiring accurate cytopathologic diagnosis for early aggressive management. STUDY DESIGN: Twenty-five cases of TCV-PTC in which the tall cells comprised at least 30% of surgically resected tumor were included in the study. The direct smears from a preoperative fine needle aspiration (FNA) and available hematoxylin and eosin cell block sections were reviewed. Ten cases of TCV-PTC were randomly selected and blinded with an equal number of conventional PTC cases. Representative slides were independently reviewed by 7 cytologists. RESULTS: In a majority of the cases, the FNA direct smears were hypercellular and displayed flat monolayer sheets of cells. Tall columnar cells with cytoplasmic tails were seen in 56% of cases. The presence of large polygonal follicular cells with abundant granular oncocytic cytoplasm and distinct cell borders was the most common feature seen in all cases. Seventeen (68%) cases displayed intranuclear pseudoinclusions in cells with abundant granular cytoplasm. A correct diagnosis of TCV-PTC was made in 30-40% of cases by 7 study participants. CONCLUSIONS: The correct recognition of TCV-PTC features in preoperative FNA is important for clinical management, and reporting these features in a cytopathology report is suggested.

Evidence-based diagnostic accuracy measurement in urine cytology using likelihood ratios.

INTRODUCTION: Recent cytology classification systems have become more evidence-based and advocate for the use of risk of malignancy (ROM) as a measure of test performance. From the statistical viewpoint, ROM represents the post-test probability of malignancy, which changes with the test result and also with the prevalence of malignancies (or pre-test probability) in each individual practice setting and individual patient presentation. Evidence-based medicine offers likelihood ratios (LRs) as a measure of diagnostic accuracy for multilevel diagnostic tests, superior to sensitivity and specificity as data binarization and information loss are avoided. LRs are used in clinical medicine and could be successfully applied to the practice of cytopathology. Our aim was to establish LRs to compare diagnostic accuracy of The Paris System for Reporting Urinary Cytology (TPS) and of a historic urine cytology reporting system. MATERIALS AND METHODS: We analyzed sequential voided urine cytology cases with histologic outcomes: 188 pre-TPS and 167 post-TPS. LRs were calculated as LR = True positive % (per category)/False positive % (per category) [95% confidence interval] and interpreted LRs = 1 nondiagnostic, LR >1 favor, LR >10 strongly favor, LRs <1 favor exclusion, and LR <0.1 strongly favor exclusion of a target condition, respectively. CATmaker open source software and Fagan nomograms were used for calculation and visualization of the corresponding post-test probability (ROM) of high-grade urothelial carcinoma (HGUC) in various scenarios. RESULTS: Both reporting systems show near-similar performance in terms of LRs, with moderate discriminatory power of negative, suspicious, and positive for HGUC test results. The atypical urothelial cell (AUC) category establishes as indiscriminate LR = 1 in the TPS, whereas in pre-TPS it favored a benign condition. We further demonstrate the utility of LRs to determine individual post-test probability (ROM) in a variety of clinical scenarios in a personalized fashion. CONCLUSIONS: The LRs allow for a quantitative performance measure in case of urine cytology across different scenarios adding numeric information on diagnostic test accuracy and post-test probability of HGUC. The diagnostic accuracy of pre-TPS and post-TPS remained similar for all but the AUC category. With the TPS, the AUC category has become genuinely diagnostically and statistically indeterminate and requires further patient investigations.

Breast implant-associated anaplastic large cell lymphoma and effusions: A review with emphasis on the role of cytopathology.

Breast implants are surgically implanted by the hundreds of thousands every year worldwide for reconstructive or aesthetic purposes. Complications related to breast implants include early and late effusions that are often submitted for cytopathological analysis, particularly to exclude the possibility of breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), a rare disease that generally follows an indolent clinical course, although it is becoming clearer that a subset of patients with adverse features have a poorer prognosis. Since a late-onset breast implant-associated effusion is the most common initial presentation of BIA-ALCL, cytopathological analysis of these effusions is considered the cornerstone and gold standard for rapid, efficient, reliable diagnosis and is critical for appropriate management and treatment. The National Comprehensive Cancer Network recently published clinical guidelines for the diagnosis and management of BIA-ALCL and stresses the essential role of cytopathological analysis, although it remains a matter of debate if all seromas should undergo immunocytochemistry or flow cytometry, particularly for assessment of expression of CD30 irrespective of morphological appearance on cytology. Herein, we review the current knowledge on BIA-ALCL, review the key cytological findings of reactive and malignant effusions related to breast implants, and present a comprehensive cytopathological workup with the presence of atypical cells as the key and pivotal element triggering further ancillary studies. We believe this approach will ensure appropriate and cost-effective management of effusion specimens from breast implants.

Surrogate indicators of sensitivity in gynecologic cytology: can they be used to improve the measurement of sensitivity in the laboratory?

BACKGROUND: Measuring the sensitivity of screening in gynecologic cytology in real life is problematic. However, other quality measures may correlate with sensitivity, including the atypical squamous cells (ASC)/squamous intraepithelial lesion (SIL) ratio. Whether these other measures can function as "surrogate indicators" for sensitivity and improve the assessment of sensitivity in the laboratory is not known. MATERIALS AND METHODS: We compared multiple quality measures with true screening sensitivity in a variety of situations. RESULTS: The abnormal rate, ASC rate, and ASC/SIL ratio were all highly correlated (r =.83 or greater) with sensitivity when the overall laboratory sensitivity was low (85%) but became less correlated (.64 or less) or uncorrelated when the screening sensitivity was higher (88% or 95%, respectively). Sensitivity was more highly correlated with the abnormal rate than the ASC/SIL ratio at low screening sensitivity. While thresholds could be set that were highly sensitive and specific for suboptimal screening, these thresholds were often less than one standard deviation away from the mean. CONCLUSION: The correlation of the abnormal rate and the ASC/SIL ratio with sensitivity depends on overall sensitivity. Standards to define minimum screening sensitivity can be defined, but these standards are relatively narrow. These features may limit the utility of these quality measures as surrogates for sensitivity.

Primary effusion lymphoma involving three body cavities.

Primary effusion lymphoma (PEL) is a human herpes virus-8 (HHV8)-associated large-cell non-Hodgkin lymphoma localized in body cavities and presenting as pleural, peritoneal, or pericardial lymphomatous effusions. It typically affects immunocompromised patients and usually involves only one body site. We describe herein a case of PEL affecting three body cavity sites in an immunocompetent patient. A 69-year-old HIV-negative man presented with upper gastrointestinal bleeding and ascites. An examination of the fluid by cytology showed large atypical lymphocytes with abundant basophilic cytoplasm, either central or eccentric nuclei having irregular outlines, and multiple prominent nucleoli. The neoplastic cells showed positive staining for CD45, CD3, HHV8 latent nuclear antigen (LNA), and Epstein-Barr virus-encoded RNA. A diagnosis of PEL was rendered. Despite chemotherapy and valganciclovir, the disease progressed to involve the pleural and pericardial cavities and the patient died 5 months following the initial diagnosis. Although PEL is a B-cell lymphoma, it is usually of null phenotype by immunohistochemistry, and can rarely aberrantly express T-cell markers, as seen in the current case. The key to the diagnosis of PEL rests on identifying HHV8 in the neoplastic cells. Therefore, restricting the term of PEL only to those cases that are HHV8 positive is important in order to differentiate PEL from other lymphomas that can present as serous effusions and that carry, in general, a more favorable prognosis than PEL.

Revitalising an academic pathology department: lessons learnt.

Pathology is a specialty that bridges basic medical science and clinical practice. In the era of personalised medicine, this specialty is facing unprecedented challenges. Some of these challenges are institution-specific, while many are shared worldwide at different magnitude. This review shares our team efforts in the past 5 years, 2012-2017, to revitalise a century-old academic pathology department in three aspects: administration, clinical service and academic development. The lessons learnt and insights gained from our experience may provide guidance to leaders in pathology or in other related specialties.

A practical guide for ancillary studies in pulmonary cytologic specimens.

Although most pulmonary cytologic specimens obtained by either exfoliation or fine needle aspirates can be reliably and accurately diagnosed based on pure morphologic criteria alone, a small proportion of cases require ancillary studies for either refining a diagnosis, for resolving a differential diagnosis or increasingly, for predictive purposes in primary lung carcinomas. This article aims to provide practical guidance on the use of common ancillary studies in pulmonary cytologic specimens. Cancer Cytopathol 2018;000:000-000. © 2018 American Cancer Society.

Implementing The Paris System for Reporting Urinary Cytology results in a decrease in the rate of the "atypical" category and an increase in its prediction of subsequent high-grade urothelial carcinoma.

BACKGROUND: In the current study, the authors evaluated the impact of implementing The Paris System for Reporting Urinary Cytology (PSRUC) on the prevalence of various cytological categories and their association with a subsequent diagnosis of high-grade urothelial carcinoma (HGUC). METHODS: A comparative study was conducted over the 6-month period before PSRUC implementation (2013), including 1653 patients and 2371 specimens versus a 6-month period after implementation of the PSRUC (2016), including 1478 patients and 2392 specimens. The following cytological categories were correlated with the subsequent biopsy result when available (355 cases): negative for HGUC (NHGUC), atypical urothelial cells (AUC), suspicious for HGUC, and HGUC. RESULTS: Although 18.6% of specimens were diagnosed as AUC in 2013, the percentage was 14.4% in 2016 (P < .0001). Concurrently, the prevalence of the "benign" category increased from 2013 to 2016 (75.4% vs 80%; P < .0001). After implementation of the PSRUC, there was no significant change noted with regard to the association between the categories of NHGUC, suspicious for HGUC, and HGUC and a subsequent HGUC biopsy diagnosis. However, the predictive value of an AUC diagnosis increased from 28.3% to 46.1% (P = .077). Most important, after the implementation of the PSRUC, there was a significant difference noted with regard to the predictive association for HGUC between the NHGUC and AUC groups (13.6% vs 46.1%; P = .003), a difference that was not found to be statistically significant before implementation of the PSRUC (18% vs 28.3%; P = .175). CONCLUSIONS: There was a much higher risk of HGUC conveyed by AUC cytology after implementation of the PSRUC, justifying more aggressive investigations of patients who receive an AUC diagnosis. Cancer Cytopathol 2018;126:207-14. © 2017 American Cancer Society.

Performance Characteristics of Cerebrospinal Fluid Cytology: An Analysis of Responses From the College of American Pathologists Nongynecologic Cytopathology Education Program.

CONTEXT: - Cerebrospinal fluid cytology is a critical diagnostic tool for the diagnosis of many conditions affecting the central nervous system. OBJECTIVE: - To assess the performance characteristics of cerebrospinal fluid cytology samples by evaluating participant interpretations within the College of American Pathologists Nongynecologic Cytopathology Education program. DESIGN: - Participant interpretations (N = 46 264) evaluated in the College of American Pathologists Nongynecologic Cytopathology Education Program were examined for concordance with the general category and with the reference diagnosis. Two nonlinear mixed models were used to analyze the concordance rates. RESULTS: - The overall concordance rates for the general category and reference diagnosis were 92.1% and 81.0%, respectively. In the malignant category, the concordance rates with the reference diagnosis were lowest for diagnoses of nonhematopoietic small blue round cell tumors (54.8%) and metastatic malignancy (77.5%); the concordance rate with the reference diagnosis was highest for leukemia/lymphoma (94.0%). In the benign category, the concordance rate was lowest for normal cerebrospinal fluid reference diagnoses (58.6%), followed by acute and chronic inflammation (64.6%), fungal infection (80.8%), and macrophages (85.3%). Significant differences in concordance were uncovered when performance was evaluated by participant type and stain technique. Leukemia/lymphoma was the most common diagnosis for misclassified nonhematopoietic small blue round cell tumor cases and negative or inflammatory cerebrospinal fluid cases. CONCLUSIONS: - This study illustrates the difficulties in achieving accurate diagnoses from cerebrospinal fluid specimens, particularly for nonhematopoietic small blue round cell tumors and normal and inflammatory cerebrospinal fluid specimens.

Update on the cytologic features of papillary thyroid carcinoma variants.

Papillary thyroid cancer (PTC), which accounts for 85-90% of all thyroid cancers, is generally an indolent tumor with long term survival rates >95%. A reliable definitive diagnosis of PTC is usually straightforward in fine needle aspirates of conventional PTC whenever the characteristic papillary and/or flat honeycomb sheet-like architecture and the typical nuclear features of chromatin pallor, nuclear enlargement, crowding, grooves and pseudoinclusions are encountered. Conventional PTC, however, has diminished in relative frequency as compared to PTC variants, especially the noninvasive follicular variant of PTC, an indolent tumor which has recently been reclassified as "noninvasive follicular thyroid neoplasm with papillary-like nuclear features" (NIFTP). These PTC variants are characterized by various architecture, cell type and shape, and stromal features, some of which can be recognized cytologically. Awareness of the cytomorphological spectrum and of the characteristic cytological features of these PTC variants is important to avoid diagnostic pitfalls. In this article, we review the different variants of PTC, including their cytomorphologic features, differential diagnosis, and salient molecular features. Diagn. Cytopathol. 2017;45:714-730. © 2017 Wiley Periodicals, Inc.

Yield of EBUS-TBNA for the diagnosis of sarcoidosis: impact of operator and cytopathologist experience.

BACKGROUND: Studies have reported a high diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for the diagnosis of sarcoidosis. We sought to review the yield of EBUS-TBNA for the diagnosis of sarcoidosis at our institution over time, and examine factors that may influence this yield. METHODS: Patients who underwent EBUS-TBNA for suspected sarcoidosis between December 2008 and November 2011 were identified. EBUS was performed without rapid on-site evaluation (ROSE) of samples. The final diagnosis was based on the results of all invasive diagnostic procedures and/or clinical follow-up. Logistic regression analysis was used to examine the effect of various factors on yield. RESULTS: 43 patients underwent 45 EBUS-TBNA procedures for suspected sarcoidosis. A total of 115 lymph nodes were sampled. The 21 G needle was used in 51% of procedures. The mean number of lymph node stations sampled was 2.6 (SD 0.7) and the mean number of needle passes per procedure was 7.8 (SD 2.0). Non-necrotising granulomatous inflammation was detected in EBUS-TBNA samples from 34/45 (76%) procedures. The overall diagnostic yield increased to 36/45 (80%) following a cytopathology review for this study. Needle gauge, number of lymph node stations sampled and number of needle passes were not associated with diagnostic yield. The yield of EBUS-TBNA increased significantly after the first 15 procedures performed for suspected sarcoidosis; the 2 additional cases diagnosed after the cytopathology review were part of this early experience. CONCLUSIONS: EBUS-TBNA is a valuable technique for the diagnosis of sarcoidosis when performed without ROSE. The yield of the procedure improved significantly over time, based on operator and cytopathologist experience.

Diagnostic concordance of non-small cell lung carcinoma subtypes between biopsy and cytology specimens obtained during the same procedure.

BACKGROUND: The objectives of this study were: 1) to determine the diagnostic concordance of non-small cell lung carcinoma (NSCLC) subtypes in cytology and biopsy specimens taken during the same procedure and evaluate the causes of discordance; and 2) to determine the frequency of immunohistochemistry (IHC) use for subtyping NSCLC. METHODS: Biopsy and cytology specimens that were obtained at the same procedure and diagnosed as NSCLC between January 2011 and December 2014 at the McGill University Health Center were identified (n = 226 pairs). The diagnostic concordance between the 2 methods was evaluated. The slides from discordant cases were reviewed, and final diagnoses were made based on IHC, resection specimens, or pathologist discussion. RESULTS: Concordance in subtype diagnosis was perfect (adeno-adeno or squamous-squamous) in 66.2% of cases and was partial (adeno or squamous vs non-small cell) in 23%; discordance (adeno vs squamous) was observed in 7.8%. Although subtyping was not possible (ie, the final diagnosis was NSCLC, not otherwise specified) in 12.8% of biopsy specimens and 16.3% of cytology specimens, specific subtyping was not achieved in only 3% of cases when both modalities were considered. IHC was used in 47% of biopsy cases and 13% of cytology cases. CONCLUSIONS: Subtyping of NSCLC can be achieved in most cases (97%) by considering findings in both biopsy and cytology specimens, and concordance in subtyping between cytology and biopsy specimens can be reached in a high percentage of cases (89.2%). Cancer Cytopathol 2016;124:737-43. © 2016 American Cancer Society.

The Canadian Area of Focused Competence (AFC) in Cytopathology experience: the first four years.

The AFC in cytopathology program was created in 2012 to address the societal need in Canada for Cytopathology leaders with in-depth specific knowledge of Cytopathology diagnostics, laboratory management, quality assurance and risk management to ensure high quality and accurate patient outcomes. So far, the developed AFC program in Cytopathology has been successfully implemented in three academic centres, and it stands as a model for competency-based advanced training in Cytopathology.

Impact of Implementing the Paris System for Reporting Urine Cytology in the Performance of Urine Cytology: A Correlative Study of 124 Cases.

OBJECTIVES: We assessed the performance of urine cytology using the Paris System for Reporting Urine Cytology (PSRUC) in comparison to our current system. METHODS: In total, 124 specimens with histologic correlation were reviewed and assigned to the PSRUC categories: benign, atypical urothelial cells (AUCs), suspicious for high-grade urothelial carcinoma (SHGUC), and high-grade urothelial carcinoma (HGUC). Original cytological diagnoses were recorded. RESULTS: Fewer cases were given an AUC diagnosis using the PSRUC in comparison to the original diagnoses (26% vs 39%), while the association of AUCs with subsequent HGUC increased from 33% to 53% with the PSRUC. Using the PSRUC resulted in a higher number of low-grade carcinomas assigned to the benign (40%) rather than the AUC (22%) category. The performance of SHGUC/HGUC diagnoses was similar in both systems (predictive value = 94%). CONCLUSIONS: The PSRUC seems to improve the performance of urine cytology by limiting the AUC category to cases that are more strongly associated with HGUC.

Morphologic Accuracy in Differentiating Primary Lung Adenocarcinoma From Squamous Cell Carcinoma in Cytology Specimens.

CONTEXT: -The National Cancer Care Network and the combined College of American Pathologists/International Association for the Study of Lung Cancer/Association for Molecular Pathology guidelines indicate that all lung adenocarcinomas (ADCs) should be tested for epidermal growth factor receptor (EGFR) mutations and anaplastic lymphoma kinase (ALK) rearrangements. As the majority of patients present at a later stage, the subclassification and molecular analysis must be done on cytologic material. OBJECTIVE: -To evaluate the accuracy and interobserver variability among cytopathologists in subtyping non-small cell lung carcinoma using cytologic preparations. DESIGN: -Nine cytopathologists from different institutions submitted cases of non-small cell lung carcinoma with surgical follow-up. Cases were independently, blindly reviewed by each cytopathologist. A diagnosis of ADC or squamous cell carcinoma was rendered based on the Diff-Quik, Papanicolaou, and hematoxylin-eosin stains. The specimen types included fine-needle aspiration from lung, lymph node, and bone; touch preparations from lung core biopsies; bronchial washings; and bronchial brushes. A major disagreement was defined as a case being misclassified 3 or more times. RESULTS: -Ninety-three cases (69 ADC, 24 squamous cell carcinoma) were examined. Of 818 chances (93 cases × 9 cytopathologists) to correctly identify all the cases, 753 correct diagnoses were made (92% overall accuracy). Twenty-five of 69 cases of ADC (36%) and 7 of 24 cases of squamous cell carcinoma (29%) had disagreement (P = .16). Touch preparations were more frequently misdiagnosed compared with other specimens. Diagnostic accuracy of each cytopathologist varied from 78.4% to 98.7% (mean, 91.7%). CONCLUSION: -Lung ADC can accurately be distinguished from squamous cell carcinoma by morphology in cytologic specimens with excellent interobserver concordance across multiple institutions and levels of cytology experience.

The Bethesda System for Reporting Thyroid Cytopathology: Proposed Modifications and Updates for the Second Edition from an International Panel.

The Bethesda System for Reporting Thyroid Cytology (TBSRTC) was proposed in 2007 at the National Cancer Institute Thyroid Fine Needle Aspiration State of the Art and Science Conference held in Bethesda, Maryland. The aim was to address the inconsistent and sometimes confusing reporting terminologies used for thyroid FNA throughout the world. The TBSRTC consists of 6 diagnostic categories, each associated with an implied risk of malignancy that translates directly into a clinical management algorithm. Since the publication of the TBSRTC cytology Atlas in January 2010, considerable experience has been gained regarding its application in cytology practice, clinical impact, and limitations. In conjunction with the International Academy of Cytology (IAC), an international panel composed of sixteen cytopathologists and an endocrinologist with special interest in thyroid cytology, including several co-authors of the 2010 TBSRTC Atlas, was created to: (1) analyze the current worldwide impact of TBSRTC, (2) report on the current state of TBSRTC based upon a review of the published literature, and (3) provide possible recommendations for a future update of TBSRTC. Herein, we summarize the panel's deliberations and key recommendations that our panel hopes will be useful during the preparation of the second edition of TBSRTC.