Cytologic-histologic Correlation Research Articles

Evolutionary analysis of indeterminate cytology and risk of malignancy in a thyroid nodule unit.

The objective of this study was to analyze the evolution in the diagnosis and management of indeterminate thyroid nodules over three time periods. 3020 patients with thyroid nodules underwent cytological evaluation during three periods (2006-2008, 2012-2014, 2017-2019). Distribution of diagnostic cytologies, risk of malignancy, diagnostic performance indices of FNA, and cytologic-histologic correlation in indeterminate cytologies were analyzed. only 2.2% of cytology tests were insufficient for a diagnosis. 86.9% cytologies were benign, 1.7% malignant, and 11.4% indeterminate. Indeterminate cytology rates were 15.9% (2006-2008), 10.1% (2012-2014), and 10% (2017-2019). Surgery was performed in 13% of benign cytology, result-ing in malignant histology in 2.7%. All malignant and suspicious cytologies underwent surgery: malig-nancy confirmed in 98% and 77% of cases, respectively. All 'indeterminate with atypia' cytologies (2006-2008) and Bethesda IV (2012-2014; 2017-2019) un-derwent surgery, with malignancy confirmed in 19.6%, 43.8%, and 25.7%, respectively. In the 'inde-terminate without atypia' category (2006-2008) and Bethesda III (2012-2014; 2017-2019), diagnostic surgery was performed in 57.7%, 78.6%, and 59.4%, respectively, with malignancy confirmed in 3.3%, 20.5%, and 31.6%. The FNA sensitivity was 91.6% with a negative predictive value greater than 96% in all periods. The specificity exceeded 75% in the last two periods. Bethesda system reduces indeterminate cytologies and improves the accuracy of FNA diagnosis. We reported a higher proportion of malignancy than expected in Bethesda III, underscoring the importance of having institution-specific data to guide decision-making. However, there is a need for risk stratification tools that allow for conservative management in low-risk cases.

Intraductal papillary mucinous neoplasms of the pancreas: Cytologic-histologic correlation study and evaluation of the cytologic accuracy in identifying high-grade dysplasia/invasive adenocarcinoma.

Intraductal papillary mucinous neoplasms (IPMNs) may be associated with invasive adenocarcinoma, low-grade dysplasia (LGD), or high-grade dysplasia (HGD). We aimed to review the cytologic-histologic correlation of cases with a histologic diagnosis of IPMN. A database search (January 2010-January 2021) was performed for resected IPMNs with preceding endoscopic ultrasound-guided fine-needle aspiration (FNA). Cytology slides were reviewed for the presence of benign, atypical, or malignant cells, and necrosis. Histologically, IPMNs were classified as benign (LGD) or malignant (HGD or adenocarcinoma). There were 41 patients with IPMN; 24 malignant and 17 benign. Sixteen of the 24 malignant IPMNs were accurately classified as malignant on cytology. There were eight false negatives and one false positive. Cytology yielded a sensitivity of 67% and a specificity of 94%. Among the 16 true positives with FNA diagnosis of adenocarcinoma, seven were IPMNs with HGD, and nine had invasive adenocarcinomas on histology. Cellular morphology and absence or presence of necrosis did not help distinguish HGD from adenocarcinoma on cytology (P > 0.5). Sampling errors and interpretative errors resulted in false-negative cases. Cytology yielded diagnoses related to IPMN in 73% of cases (30/41) and lack of identification of mucinous cells/mucinous background resulted in interpretative errors (9). This study shows that there is a good correlation between cytopathology and surgical pathology diagnoses of IPMNs and that cytology is mostly able to recognize IPMN with HGD/adenocarcinoma. However, heterogeneity in areas of IPMN with HGD/adenocarcinoma may result in sampling errors yielding false-negative cases. Mucinous cells/background should raise the suspicion of IPMN on cytology, even when no neoplastic epithelium is present for the evaluation of dysplasia.

Atypical glandular cells in Pap tests: cytology-histology correlation and risk assessment with human papillopmavirus (HPV) testing

Atypical glandular cells (AGC) represent less than 1% of Pap test cases and include a variety of lesions in both the cervix and endometrium. The study aimed to investigate the cytology-histology correlation in AGC patients and to evaluate the clinical utility of hrHPV testing in this diagnostic context. We identified 491 atypical glandular cells (AGC) cases in our quality analysis (QA) database of 336,064 Pap tests interpreted between March 1, 2013 and July 12, 2016. Of these, 251 cases had follow-up biopsies with hrHPV tests in 148 cases. The most common histologic diagnosis associated with AGC was normal/benign or low-grade lesions, comprising 55% of cervical biopsies and 24% of endometrial biopsies. High-grade lesions were identified in 21% of follow-up biopsies. In patients with AGC cytology, a positive hrHPV test significantly increased the likelihood of cervical HSIL or above lesions on biopsy by 26.4 times (OR = 26.4, 95% CI: 5.8-119.4, P < 0.0001). A positive genotyping result for HPV 16 dramatically increased the likelihood of cervical HSIL or above lesions on biopsy (OR = 84, 95% CI: 12.0-590.5, P < 0.0001). The HPV test had a negative predictive value of 97% (CI: 85%-100%). Our study confirms that AGC is a significant diagnosis with an overall risk for high-grade cervical or endometrial lesions as high as 21%. hrHPV testing with genotyping is an effective tool for identifying high-risk individuals within the AGC population, with excellent positive and negative predictive values. This approach is valuable for clinical risk stratification and differential diagnosis in patients with AGC cytology.

Liquid-Based Cervical Cytology: Monitoring the Laboratory Quality Indicators.

Many developments in cervical cancer screening have happened in the past century, helping women in earlier detection of cervical cancer and its precursors. Cytology still holds the fort as being a specific test, though it suffers in sensitivity. As a part of the quality control program, the aim of the study is to determine the total number of abnormal liquid-based cervical cytology (LBC) at our center and correlate the abnormal LBC with histology and human papillomavirus (HPV) DNA test results. Retrospective analysis of 4286 LBC screening cases was carried out over a period of 5 years. For cytology-histology correlation, cervical biopsy and cytology test results were analyzed. The two-tier grading system for biopsy interpretation was used. HPV DNA test results wherever available were correlated. Of the 4286 LBC cases, 157 samples (3.7%) were unsatisfactory for evaluation, 3915 samples (91.3%) were negative for intra-epithelial lesion or malignancy, and 214 samples (5%) showed epithelial cell abnormality. ASC-US was reported in 60 cases (1.4%), ASC-H in 35 cases (0.8%), LSIL in 47 cases (1.1%), HSIL in 41 cases (1.0%), squamous cell carcinoma in a single case (0.02%), and atypical glandular cells in 30 cases (0.7%). The ASC/SIL ratio was 1.07:1. The CHC major discrepancy was calculated as 16.2%. The concordance of HSIL on cytology and biopsy as a measure of PPV is 94.4%. Of the epithelial cell abnormalities, 24 cases were positive for high-risk HPV (hrHPV). Molecular test results of 2737 samples showed HPV detected in 50 cases, of which 24 cases were positive for hrHPV. The study helped us to analyze the quality parameters of our cytopathology laboratory which are within the acceptable limits.

Cytologic-Histologic Correlation Practices for Nongynecologic Cytology Specimens: A Survey by the College of American Pathologists Cytopathology Committee.

Cytologic-histologic correlation (CHC) is a Clinical Laboratory Improvement Amendments-mandated requirement for gynecologic cytology, but no similar requirement exists for nongynecologic cytology. This study presents the findings from a College of American Pathologists' survey of nongynecologic cytology practice patterns. To survey the current CHC practices for nongynecologic cytology. Data were analyzed from a survey developed by the committee and distributed to participants in the Nongynecologic Cytopathology Education Program mailing. Adoption of CHC for nongynecologic cytology cases is worldwide, with 88.5% of institutions performing CHC on these specimens, a substantial increase from previous years. Performance of CHC varied by institution type, with clinic or regional/local independent laboratories and national/corporate laboratories performing CHC significantly less frequently than hospitals, university hospitals/academic medical centers, and Veterans Administration/Department of Defense hospital institutions. Most CHC was performed concurrently in real time, when the corresponding surgical specimen was reviewed. Selection for real-time concurrent CHC was by the interpreting pathologist, the pathologist diagnosing the surgical biopsy sample or cytopathology case, or both. Sampling was by far the most common reason for discordance. A 2-step difference was the most frequent threshold for discordance between cytology and surgical specimens, but this criterion varied among institutions, with no majority definition. The positive predictive value of a positive cytology finding was calculated rarely in North American institutions but was calculated more frequently in international institutions. CHC practices for nongynecologic cytopathology mirror those found for CHC of gynecologic cytopathology.

Molecular-derived risk of malignancy and the related positive call rate of indeterminate thyroid cytology diagnoses as quality metrics for individual cytopathologists.

Indeterminate thyroid cytopathology diagnoses represent differing degrees of risk that are corroborated by follow-up studies. However, traditional cytologic-histologic correlation may overestimate the risk of malignancy (ROM) because only a subset of cases undergo resection. Alternatively, some molecular tests provide probability of malignancy data to calculate the molecular-derived risk of malignancy (MDROM) and the positive call rate (PCR). The authors investigated MDROMs and PCRs of indeterminate diagnoses for individual cytopathologists as quality metrics. This study was approved by the Department of Pathology Quality Improvement Program. Thyroid cytopathology diagnoses and ThyroSeq v3 results were retrieved for each cytopathologist for a 2-year period with at least 3years of follow-up for the atypia of undetermined significance (AUS), follicular neoplasia (FN), and follicular neoplasia, oncocytic-type (ONC) cytopathologic diagnoses. MDROMs and PCRs were compared with reference ROMs and cytologic-histologic correlation outcomes. The overall MDROMs (and ranges for cytopathologists) for the AUS, FN, and ONC categories were 13.4% (range, 5.8%-20.8%), 28.1% (range, 22.1%-36.7%), and 27.0% (range, 19.5%-41.5%), respectively, and most individual cytopathologists' MDROMs were within reference ROM ranges. However, PCRs more effectively parsed the differences in cytopathologists' ROM performance. Although the overall PCRs were not significantly different across cytopathologists (p=.06), the AUS PCRs were quite different (p=.002). By cytologic-histologic correlation, six of 55 resected cases (10.9%) were falsely negative, and there were no false-positive cases. MDROMs and PCRs evaluate concordance with reference ROMs and with one another and provide individual feedback, which potentially facilitates quality improvement.

Using Natural Language Processing and Machine Learning Techniques for Cytology-Histology Correlation Saves Cytotechnologist Time without Compromising Quality

Using Natural Language Processing and Machine Learning Techniques for Cytology-Histology Correlation Saves Cytotechnologist Time without Compromising Quality

Use of nongynecologic cytologic-histologic correlation to identify patterns of error: An institutional experience.

Quality management practices empower cytology laboratories to deliver consistent, high-quality patient care. Monitoring of key performance indicators is one way by which laboratories can identify patterns of error and focus their improvement activities. Cytologic-histologic correlation (CHC) identifies error by retrospectively reviewing cytology cases when discordant surgical pathology diagnoses are reported. Analysis of CHC data can elucidate patterns of error and direct quality improvement initiatives. CHC data of nongynecologic cytology specimens were reviewed over a 3-year period (2018-2021). Errors were separated by anatomic site and classified as either sampling or interpretive errors. A total of 364 discordant cases were identified out of 4422 cytologic-histologic pairs (a discordant rate of 8%). The majority (272; 75%) were sampling errors, with fewer interpretive errors (92; 25%). Sampling errors were found to occur most commonly in lower urinary tract and lung. Interpretive errors were most commonly found in lower urinary tract and thyroid. Nongynecologic CHC data can be a valuable resource for cytology laboratories. By studying the types of errors, quality improvement activities can be targeted toward problem areas.

Cytology-histology correlation, time to diagnosis and time to therapy when cytology is performed in addition to biopsies in malignant spinal lesions of previously unknown malignant disease.

e14007 Background: Metastatic spinal lesions are the first manifestation of malignant disease in up to 30% of patients (pts). Spinal care, diagnostic evaluation and initiation of systemic therapy are crucial for outcome in pts with advanced cancer. Histopathology (HP) from bone specimens is time consuming and decalcification procedure can hamper diagnostic information. The additional evaluation of spinal lesions by cytopathology (CP) has the potential to reduce time to diagnosis (TTD) and time to therapy (TTT). Therefore, we performed simultaneous analysis of CP and HP specimens from suspected malignant spinal lesions to evaluate the diagnostic value of additional CP. This work was supported by the German Society for Spine Surgery (DWG). Methods: We obtained CP specimens by transpedicular, intralesional aspiration through a Yamshidi needle or touch preparation from solid tissue samples. CP and HP specimens from spinal lesions were evaluated in parallel in 54 pts (CP/HP group). We analyzed sensitivity and specificity of CP in reference to HP. Furthermore, we compared the TTD and TTT of CP/HP group with a retrospective cohort of 103 patients in whom only HP was performed (HP group). Results: The collection of CP samples was feasible without elongation of surgery time or any complications for the pts. In 52/54 (96%) pts a CP-specimen was successfully obtained. Of the 52 pts analyzed, multiple myeloma was diagnosed in 10 pts, solid malignancy in 34, 1 pt had lymphoma and 7 did not show malignancy. The most common solid malignancies were prostate cancer (n=9), breast cancer (n=5) and adenocarcinoma of the lung (n=5). The sensitivity and specificity of CP in reference to HP is 98% and 71%, respectively. The concordance of CP and HP in differentiating between hematologic or solid neoplastic lesions is 94.2%. TTD in the CP/HP group was significantly shorter compared to HP group (1.7±1.8 and 8.6±3.6 d, respectively; p&lt;0.001). In addition, TTT in the CP/HP group was significantly shorter than in the HP group (19.3±14.4 d and 31.4±24.7 d; p=0.003). In 24.1% of pts a specific tumor therapy was initiated based on CP diagnosis before obtaining the results of HP. Conclusions: The evaluation of CP from malignant spinal lesions shows high sensitivity and concordance with HP and reduced TTD and TTT. Therefore, CP in addition to HP from spinal lesions of suspected malignancy has the potential to improve quality of life and prognosis in pts with advanced cancer. We therefore recommend the implementation of additional CP to HP in previously undiagnosed malignant spinal lesions.

Update on Salivary Gland Fine-Needle Aspiration and the Milan System for Reporting Salivary Gland Cytopathology.

Fine-needle aspiration (FNA) is a well-established procedure for the diagnosis and management of salivary gland lesions, despite challenges imposed by salivary gland tumor diversity, complexity, and cytomorphologic overlap. Until recently, the reporting of salivary gland FNA specimens was inconsistent among different institutions throughout the world, leading to diagnostic confusion among pathologists and clinicians. In 2015, an international group of pathologists initiated the development of an evidence-based tiered classification system for reporting salivary gland FNA specimens, the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC). The MSRSGC consists of 6 diagnostic categories, which incorporate the morphologic heterogeneity and overlap among various nonneoplastic, benign, and malignant lesions of the salivary glands. In addition, each MSRSGC diagnostic category is associated with a risk of malignancy and management recommendations. To review the current status of salivary gland FNA, core needle biopsies, ancillary studies, and the beneficial role of the MSRSGC in providing a framework for reporting salivary gland lesions and guiding clinical management. Literature review and personal institutional experience. The main goal of the MSRSGC is to improve communication between cytopathologists and treating clinicians, while also facilitating cytologic-histologic correlation, quality improvement, and research. Since its implementation, the MSRSGC has gained international acceptance as a tool to improve reporting standards and consistency in this complex diagnostic area, and it has been endorsed by the 2021 American Society of Clinical Oncology management guidelines for salivary gland cancer. The large amount of data from published studies using MSRSGC served as a basis for the recent update of the MSRSGC.

Comparison of small biopsy and cytology specimens: Subtyping of pulmonary adenocarcinoma.

The aims of this study was to investigate the use of cytologic samples for subclassification of lung adenocarcinoma and the cytologic-histologic correlation in lung adenocarcinoma subtypes using small samples. Cytological characteristics of lung adenocarcinoma subtypes were summarized by a literature review. Cytology samples from 115 patients with lung adenocarcinoma confirmed by small biopsies were classified by subtype. The diagnostic concordance of subtypes between biopsy and cytology samples was assessed. Among the 115 cases, 62 (53.9%) had acinar predominant pattern, 16 (13.9%) were papillary predominant pattern, 29 (25.2%) had solid predominant pattern, 3 (2.6%) had lepidic predominant pattern, and 5 (4.3%) had micropapillary predominant pattern. All corresponding cytologic samples were classified into five subtypes based on cytomorphology features, with concordance rates of 74.2% (46 patients) in c-acinar subtype, 56.3% (nine patients) in c-papillary subtype, 24.1% (seven patients) in c-solid subtype, 66.7% (two patients) in c-lepidic subtype, and 40% (two patients) in c-micropapillary subtype. Collectively, the cytology and small biopsy concordance rate was approximately 57.4%. Subtyping of lung adenocarcinoma using cytologic specimens is challenging and the consistency rate varies with the subtype. Acinar predominant tumors have an excellent cytologic-histologic correlation compared to tumors with predominant solid or micropapillary pattern. Evaluating cytomorphologic features of different lung adenocarcinoma subtypes can reduce the false-negative rate of lung adenocarcinoma, particularly for the mild, atypical micropapillary subtype, and improve diagnostic accuracy.

Cervical cytology results among pregnant and non-pregnant women in Brazil

ObjectiveTo compare the prevalence of abnormal cervical smear results among pregnant and non-pregnant women with and without representation of the transformation zone (TZ) in a mid-sized city in Brazil. Study designThis observational analytical and retrospective study analyzed cervical smear results from pregnant and non-pregnant women in a mid-sized city in Brazil. Private data were collected at private clinics over seven years and from public services over 16 years. All results were reported according to Bethesda System. Pregnant women were separated from non-pregnant women, and women were stratified into two age groups (25–29 years and 30–34 years) in general analyses. For TZ representation and cytologic-histologic correlation, there was no age stratification. ResultsAmong public services cervical smears, the frequency of atypical squamous cells of undetermined significance (ASC-US) was higher for pregnant women in the entire group (odds ratio [OR] 1.91; confidence interval [CI] 1.07–3.39) and among women from 30 to 40 years old (OR 2.79; CI 1.38–5.66). The same occurred for low-grade squamous intraepithelial lesion (LSIL) in the total group (OR 3.50; CI 1.44–8.53) and among women 30 to 40 years old (OR 4.57; CI 1.45–14.42).The frequency of ASC-US was higher in pregnant women with TZ representation exams than those without (OR 4.62; CI 2.17–9.84). The same occurred for those with atypical squamous cells, which cannot exclude high-grade squamous intraepithelial lesion (OR 9.81; CI 1.63–59.15) and LSIL (OR 10.47; CI 3.39–32.36).Among pregnant women with abnormal cervical smear results, 85.74% were followed up through cytology, and an average of 26.12% of patients underwent biopsy, of which almost all were positive for dysplasia. ConclusionPregnant and non-pregnant women did not differ in cervical smears with actual precursor lesions. Nevertheless, considering the opportunistic nature of Brazilian cervical cancer screening, prenatal visits present an opportunity to perform cervical smears in pregnant women. TZ representation correlated with higher rates of abnormal cervical smears, reinforcing the clinical importance of endocervical/metaplastic cell representation, including among pregnant women.

Cytologic-Histologic Correlation of Musculoskeletal Lesions, an Examination of the Proposed Cytology Reporting System

Cytologic-Histologic Correlation of Musculoskeletal Lesions, an Examination of the Proposed Cytology Reporting System

Cytology-histology correlation of cervical Papanicolaou smears and biopsies performed at a single institution compared to those performed at different institutions.

Cytology-histology correlation (CHC) is the gold standard of quality assurance in cytology laboratories to ensure appropriate patient treatment, and as an educational tool for cytology laboratory personnel. If cervical Pap smears (CPs) and cervical biopsies (CBs) are performed at different institutions, these benefits may be lost. All CBs performed at our institution from 1 January 2019 to 31 December 2019 with adequate CPs performed in the 6 months prior to the CB were included in this retrospective review. We compared the CHC for CPs and CBs performed at a single institution to the CHC for CPs and CBs performed at different institutions, with a focus on the proportion of overcalls on CPs, as those are the most challenging discrepant CHC to manage clinically. We used the American Society of Cytology guidelines for our discrepancy assessment grid. A Chi-squared test was used to compare the proportions of the populations. The P-value was set at < 0.05. Of the 305 CBs in our study population, 69 had a CP performed at our institution and 236 had a CP performed at an outside institution. The CHC for CBs and CPs performed at a single institution showed statistically significantly less disagreement than the CHC for those performed at different institutions (P < 0.05). Further, CBs and CPs performed at a single institution had statistically significantly fewer overcalls than CBs and CPs performed at different institutions (P < 0.05). This study further supports the use of CHC, and in light of our findings we recommend that a patient's CPs and CBs are performed at the same institution. If performing a CP and CB at the same institution is not feasible, a prospective consultation review of the CP by the institution performing the CB should be strongly considered. Further study, including an evaluation of the reason for the discrepancy in discordant cases may better elucidate the reasons for better CHC agreement when CP and CB are performed at the same institution.

Follicular Neoplasm of Thyroid Revisited: Current Differential Diagnosis and the Impact of Molecular Testing.

The diagnosis of "follicular neoplasm" (FN) in thyroid cytopathology has a long history that originated not long after the practice of fine-needle aspiration (FNA) of thyroid nodules. From the outset, this interpretive category was intended to convey a set of differential diagnoses rather than a precise diagnosis, as key diagnostic features, such as capsular and vascular invasion, were not detectable on cytology preparations. Cytologic-histologic correlation studies over the past several decades have shown that FN interpretation can be applied to the spectrum of nonneoplastic tumors to carcinomas. Most tumors classified as FN include follicular adenoma, follicular carcinoma, noninvasive follicular thyroid tumor with papillary-like nuclear features, and follicular variant of papillary thyroid carcinoma. Less common entities that may be classified as FN on FNA include hyalinizing trabecular tumor (HTT), poorly differentiated thyroid carcinoma, medullary carcinoma, and nonthyroidal lesions such as parathyroid tissue, paraganglioma, and metastatic tumors. Advances in our ability to detect characteristic molecular alterations (eg, GLIS gene rearrangements for hyalinizing trabecular tumor) in FNA samples may assist in the identification of some of these entities. In this review, we summarize the pathophysiology, history, and evolution of the terminology and the current differential diagnosis according to the recently published 2022 World Health Organization classification, molecular testing, and management of nodules classified as FN.

Application of the Milan System for Reporting Salivary Gland Cytopathology: A Single Institutional Experience of 354 Cases with Cytologic-Histologic Correlation

Background: Evaluation of salivary gland lesions is routinely done preoperatively by fine-needle aspiration cytology (FNAC). The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC), with diagnostic categories I–VI, has been recommended to standardize the reporting of salivary gland lesions by FNAC. We aimed to reclassify archival salivary gland FNAC samples using MSRSGC, correlate the samples with surgical resections, and calculate the risk of malignancy (ROM) for each category. Methods: A total of 354 salivary gland FNAC samples (2013–2018) were reviewed. All FNAC results were retrospectively classified according to the MSRSGC. All cases had surgical follow-up. Histology was used to calculate the ROM, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy. Results: The 354 aspirates were classified as: nondiagnostic (ND) 17.0% (60), non-neoplastic (NN) 1.4% (5), atypia of undetermined significance (AUS) 11.0% (39), benign neoplasm (BN) 49.4% (175), salivary gland neoplasms of unknown malignant potential (SUMP) 10.7% (38), suspicious for malignancy (SM) 3.4% (12), and malignant (M) 7.1% (25). The ROM was as follows: ND 22%, NN 20%, AUS 15%, BN 2%, SUMP 53%, SM 75%, and M 96%. The diagnostic accuracy for separating benign versus malignant neoplasms was 96%. Cytologic-histologic correlation yielded a false-negative rate of 2.7%, false-positive rate of 10.5%, PPV of 89%, NPV of 97%, sensitivity of 87%, and specificity of 98%. Conclusion: MSRSGC helps standardize cytology reports, provides useful information for appropriate clinical management, and ensures the best care of patients with salivary gland lesions.

Malignant Cells in Urine Cytology: Not Always High-Grade Urothelial Carcinoma

Abstract The main purpose of urine cytology is the detection of high-grade urothelial carcinoma (HGUC). When malignant cells of nonurothelial origin are present, it is often misdiagnosed as HGUC due to the rarity of this event and difficulty in distinguishing subtle cytomorphologic differences. To arrive at the appropriate diagnosis, evaluation of urine cytology specimens requires correlation with clinical and radiologic findings and utilization of cytologic-histologic correlation. We present the case of a 64-year-old woman with gross hematuria. Imaging located an infiltrative mass involving the left renal pelvis, highly suggestive of urothelial carcinoma. Lymphadenopathy and multiple bony lesions in the spine were concerning for metastatic disease. Urine cytology specimens taken during cystoscopy contained malignant cells, which were interpreted as HGUC. The workup of a subsequent lymph node biopsy showed a metastatic high grade carcinoma of renal origin with SMARCB1 loss. This finding led to the reexamination of the urine cytology specimens, revealing the malignant cells were not HGUC but rather renal carcinoma. This case highlights a potential pitfall in the evaluation of urine cytology and the importance of cytologic-histologic correlation.

Current State of Cytologic-Histologic Correlation Implementation for North American and International Laboratories: Results of the College of American Pathologists Cytopathology Committee Laboratory Practices in Gynecologic Cytology Survey.

The College of American Pathologists (CAP) updated the Laboratory Accreditation Program Cytopathology Checklist to assist laboratories in meeting and exceeding the Clinical Laboratory Improvement Amendments standards for gynecologic cytologic-histologic correlation (CHC). To survey the current CHC practices. Data were analyzed from a survey developed by the committee and distributed to participants in the CAP Gynecologic Cytopathology PAP Education Program mailing. Worldwide, CHC practice is nearly universally adopted, with an overall rate of 87.0% (568 of 653). CHC material was highly accessible. CHC was commonly performed real time/concurrently at the time the corresponding surgical pathology was reviewed. Investigation of CHC discordances varied with North American laboratories usually having a single pathologist review all discrepant histology and cytology slides to determine the reason for discordance, while international laboratories have a second pathologist review histology slides to determine the reason for discordance. The cause of CHC discordance was primarily sampling issues. The more common statistical metrics for CHC monitoring were the total percentage of cases that correlated with subsequent biopsies, screening error rate by cytotechnologist, and interpretative error rate by cytotechnologist. Many laboratories have adopted and implemented the CHC guidelines with identifiable differences in practices between North American and international laboratories. We identify the commonalities and differences between North American and international institutional practices including where CHC is performed, how CHC cases are identified and their accessibility, when CHC is performed, who investigates discordances, what discordances are identified, and how the findings affect quality improvement.

Application of the Milan System for Reporting Salivary Gland Cytopathology in pediatric patients: An international, multi-institutional study.

Pediatric salivary gland fine-needle aspiration (FNA) is uncommon with a higher frequency of inflammatory lesions and a small proportion of malignancies. This international, multi-institutional cohort evaluated the application of the Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) and the risk of malignancy (ROM) for each diagnostic category. Pediatric (0- to 21-year-old) salivary gland FNA specimens from 22 international institutions of 7 countries, including the United States, England, Italy, Greece, Finland, Brazil, and France, were retrospectively assigned to an MSRSGC diagnostic category as follows: nondiagnostic, nonneoplastic, atypia of undetermined significance (AUS), benign neoplasm, salivary gland neoplasm of uncertain malignant potential (SUMP), suspicious for malignancy (SM), or malignant. Cytology-histology correlation was performed where available, and the ROM was calculated for each MSRSGC diagnostic category. The cohort of 477 aspirates was reclassified according to the MSRSGC as follows: nondiagnostic, 10.3%; nonneoplastic, 34.6%; AUS, 5.2%; benign neoplasm, 27.5%; SUMP, 7.5%; SM, 2.5%; and malignant, 12.4%. Histopathologic follow-up was available for 237 cases (49.7%). The ROMs were as follows: nondiagnostic, 5.9%; nonneoplastic, 9.1%; AUS, 35.7%; benign neoplasm, 3.3%; SUMP, 31.8%; SM, 100%; and malignant, 100%. Mucoepidermoid carcinoma was the most common malignancy (18 of 237; 7.6%), and it was followed by acinic cell carcinoma (16 of 237; 6.8%). Pleomorphic adenoma was the most common benign neoplasm (95 of 237; 40.1%). The MSRSGC can be reliably applied to pediatric salivary gland FNA. The ROM of each MSRSGC category in pediatric salivary gland FNA is relatively similar to the ROM of each category in adult salivary gland FNA, although the reported rates for the different MSRSGC categories are variable across institutions.

Cervical Cytology-Histology Correlation Based on the American Society of Cytopathology Guideline (2017) at the Russian National Medical Research Center for Obstetrics, Gynecology, and Perinatology.

Recent evidence suggests that a cytology–histology correlation (CHC) with discrepancy detection can both evaluate errors and improve the sensitivity and specificity of the cytologic method. We aimed to analyze the errors in cytologic–histologic discrepancies according to the CHC protocol guideline of the American Society of Cytopathology (2017). This retrospective study included 273 patients seen at the National Medical Research Center of Obstetrics, Gynecology and Perinatology (Moscow, Russia) between January 2019 and September 2021. The patients’ mean age was 34 ± 8.1 years. The cytology–histology agreement was noted in 158 cases (57.9%). Major discrepancies were found in 21 cases (7.6%), while minor discrepancies were noted in 93 cases (34.1%). The reason for 13 (4.8%) discrepancies was a colposcopy sampling error and, in 46 (16.8%) cases, the reason was a Papanicolaou (PAP) test sampling error. The discrepancy between primary and reviewed cytology was due interpretive errors in 13 (4.8%) cases and screening errors in 42 (15.4%) cases. We demonstrated that the ASC guidelines facilitate cervical CHC. A uniform application of these guidelines would standardize cervical CHCs internationally, provide a scope for the inter-laboratory comparison of data, and enhance self-learning and peer learning.