International Academy of Cytology Guidelines Based Categorization of Breast Fine-Needle Aspiration Cytology Lesions and their Histopathological Correlation

Introduction: Breast cancer affects 2.1 million women each year and is the most common cancer among females, followed by lung, colorectum, uterus, and cervix. Breast cancer accounted for 6,26,679 (6.6%) deaths in 2018. Breast cancer incidence is on the rise in every part of the globe, including developed countries. Fine Needle Aspiration Cytology (FNAC) shows high sensitivity, specificity, and accuracy in evaluation of breast lesions. FNAC is part of the triple test and is the gold standard for assessment. The new reporting system for breast FNAC, proposed by the International Academy of Cytology (IAC) Yokohama Breast Cytopathology System, has standardised the reporting system to categorise breast lesions and as unmasked the diagnostic dilemma faced by reporting cytopathologist. Aim: The study aimed to categorise the samples according to IAC Yokohama Breast Cytopathology System and assess the Risk of Malignancy (ROM) for each category and increase the diagnostic yield of breast FNAC. Materials and Methods: A retrospective cohort study included 1,467 breast FNAC cases, which were retrieved and reclassified based on the newly proposed IAC Yokohama System into five categories during January 2017-December 2018 in Kidwai Memorial Institute of Oncology (KMIO), Bangalore. Histopathology correlation was done, and the Risk of Malignancy (ROM) was assessed whenever possible. The study results were analysed using Microsoft excel 2007, sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV), and accuracy ratios were calculated using the MedCalc diagnostic test evaluation calculator, keeping histologic diagnosis as the gold standard. Results: Re-categorisation of 1,467 cases was done according to the Yokohama breast cytopathology system as insufficient material, benign, atypical, suspicious for malignancy, and malignant. The histopathology diagnosis was available in 1,069 cases. The respective ROM for each category was, 7.6% for category 1 (Insufficient), 15.26% for category 2 (Benign), 65.38% for category 3 (Atypical), 83.33% for category 4 (Suspicious) and 99.18% for category 5 (Malignant). Considering malignant cases as positive, sensitivity-86.75%, specificity-97.32%, PPV-99.19%, NPV-66.06% and accuracy of 88.96% was deduced. Conclusion: It is recommended to incorporate the IAC Yokohama system to categorise breast cytopathology with uniform terminologies. This will help diagnose breast lesions more consistently and accurately, which in turn helps the clinician manage the disease and predict the ROM and the patient outcome.

Breast cancer is the leading cause of cancer deaths among women worldwide. Fine needle aspiration cytology (FNAC) and breast sonography have played a pivotal role in the characterization of a breast lump. The main objective of this study was to analyze the correlation between the International Academy of Cytology (IAC) Yokohama for Reporting Breast Fine Needle Aspiration Biopsies (FNAB) and breast imaging reporting and data system (BIRADS) for sonography along with histopathological correlation. A total of 135 FNAC specimens were categorized according to the IAC Yokohama system and BIRADS reporting system and their correlation with histopathology wherever possible to calculate the risk of malignancy (ROM). According to IAC Yokohama categorization, the cases in categories I, II, III, IV, and V were 1,78,8,6 and 42, respectively. Akin to cytology, most of the cases were assigned BIRADS score two followed by score 6, with the Pearson's correlation coefficient between the IAC Yokohama system for reporting breast cytology and BIRADS scoring system of 1.957 with a P-value < 0.001 (strong correlation). The sensitivity, specificity, PPV, NPV, and DA of FNAC with category III assumed as malignant were 98.9%, 85%, 76.1%, 99.3%, and 89.5%, respectively. Histopathological correlation was available for 90 cases. The ROM for categories II, III, IV, and V was 5.6%,37.5%,100%, and 100%, respectively. IAC Yokohama system of reporting breast cytopathology and BIRADS serves as a common language of communication between pathologists and clinicians and aid in better stratification of the lesions. Both FNAC (minimally invasive) and ultrasound (non-invasive imaging technique) are diagnostic tools that complement each other for patient diagnosis and management.

Recently the International Academy of Cytology (IAC) introduced a new reporting system for breast fine-needle aspiration cytology that classifies cytologic diagnoses into five-categories: (I) insufficient material, (II) benign, (III) atypical, (IV) suspicious of malignancy, and (V) malignant. The current study was undertaken to categorize the breast lesions utilizing the newly proposed IAC Yokohama classification system and evaluate the risk of malignancy (ROM) for respective categories and the diagnostic yield of this technique. All FNAs of breast lesions over 2.5 years were categorized retrospectively using the newly proposed IAC Yokohama reporting system. The ROM was calculated along with sensitivity, specificity, positive and negative predictive value, diagnostic accuracy, false positive, and false-negative rate using the histological diagnosis as the gold standard. The 512 cases were distributed as follows: Category I (insufficient material) 7.4%, Category II (benign) 74%, Category III (atypical) 5.7%, Category IV(suspicious) 1.4%, and Category V (malignant) 11.5%. Histopathological correlation was available in 285 (55.7%) cases. The respective ROM calculated was 33.3%, 0.5%, 13.3%, 83.3%, and 100% for Category I-V. The Sensitivity, Specificity, Positive and Negative Predictive Value, and Diagnostic accuracy were 95%, 99.5%, 98.27%, 98.6, and 98.5% respectively. Despite previous attempts to establish a standardized diagnostic terminology, there has been a lack of a single internationally approved standardized reporting system allowing substantial diagnostic clarity and incorporating distinct diagnostic categories, each linked with a specific ROM and recommended management. This System also provides enhanced communication between pathologists and attending clinicians for the benefit of the patient.

Objective: The International Academy of Cytology (IAC) Yokohama system was used to categorize breast lesions as the major goal of this investigation. Methods: Between January 2022 and March 2023, this study on breast fine needle aspiration cytology (FNAC) was carried out at a tertiary care facility in north India. This System of reporting breast cytopathology was used to classify a total of 100 patients. Histopathology correlation was available in 40 cases; Malignancy risk, sensitivity, specificity, and diagnostic precision were assessed. Results: Breast FNAC cytology was divided into five groups using the new IAC Yokohama system and discovered C1: Insufficient material (6%), C2: Benign type (72%), C3: Atypical type (05%), C4: Suspicious type of malignancy (06%), C5: Malignancy (11%). When histopathological reports were available, FNACs were connected with them. The likelihood of cancer, the precision, sensitivity, and specificity of the diagnosis were all calculated. Conclusion: The IAC Yokohama System for reporting breast cytopathology governs how breast FNAC are categorized, which offers an excellent method for reporting breast cytopathology with a uniform method of reporting and clear definition of each category as well as clear communication between pathologists and clinicians regarding the risk of malignancy and subsequent management.

Background: Benign and malignant lesions of breast are one of the most common causes of palpable masses seen in women. Fine-needle aspiration cytology (FNAC) is the important modality of diagnosis of breast lumps. Previously, there were no uniform criteria for reporting breast FNAC. To overcome this problem, the newly designed system – International Academy of Cytology (IAC) – Yokohama system of reporting was implemented in 2016. The system offers a structured report to the patient. Aims and Objectives: This study aims to categorize breast FNAC according to the IAC – Yokohama system of reporting, to calculate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of the test, and to analyze the cytomorphological spectrum of various breast lesions. Materials and Methods: A total of 210 patients presenting with breast lump in cytology section were subjected to FNAC using a 22 gauge needle under all aseptic precautions. Detailed clinical history was taken. All cytology and histopathology examination slides (wherever available) were thoroughly studied. FNAC smears were reported using IAC – Yokohama system of reporting. Results: In our study, benign category (C2) was most commonly seen in 73.33% of cases, followed by 10.48% of cases of atypical probably benign (C3), 2.38% of cases were reported as suspicious (C4), and 11.43% of cases were reported as malignant (C5). Cytohistopathological concordance was seen in 38 cases (88.4%) whereas five cases were reported as discordant. Sensitivity and specificity of the test for the diagnosis of malignancy were 81% and 100%, respectively. PPV was 100%. NPV was 90.90%. Diagnostic accuracy of the test was 93.47%. Conclusion: The newer IAC – Yokohama system of reporting of breast FNAC is simple, has clear diagnostic criteria hence boost up the confidence as well has uniformity of reporting by cytopathologist, and increases the understanding and uniformity in assessment by the attending clinician which help in improving the communication between the pathologist and the treating clinician.

Background: Benign and malignant lesions of breast are one of the most common causes of palpable masses seen in women. Fine-needle aspiration cytology (FNAC) is the important modality of diagnosis of breast lumps. Previously, there were no uniform criteria for reporting breast FNAC. To overcome this problem, the newly designed system – International Academy of Cytology (IAC) – Yokohama system of reporting was implemented in 2016. The system offers a structured report to the patient. Aims and Objectives: This study aims to categorize breast FNAC according to the IAC – Yokohama system of reporting, to calculate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of the test, and to analyze the cytomorphological spectrum of various breast lesions. Materials and Methods: A total of 210 patients presenting with breast lump in cytology section were subjected to FNAC using a 22 gauge needle under all aseptic precautions. Detailed clinical history was taken. All cytology and histopathology examination slides (wherever available) were thoroughly studied. FNAC smears were reported using IAC – Yokohama system of reporting. Results: In our study, benign category (C2) was most commonly seen in 73.33% of cases, followed by 10.48% of cases of atypical probably benign (C3), 2.38% of cases were reported as suspicious (C4), and 11.43% of cases were reported as malignant (C5). Cytohistopathological concordance was seen in 38 cases (88.4%) whereas five cases were reported as discordant. Sensitivity and specificity of the test for the diagnosis of malignancy were 81% and 100%, respectively. PPV was 100%. NPV was 90.90%. Diagnostic accuracy of the test was 93.47%. Conclusion: The newer IAC – Yokohama system of reporting of breast FNAC is simple, has clear diagnostic criteria hence boost up the confidence as well has uniformity of reporting by cytopathologist, and increases the understanding and uniformity in assessment by the attending clinician which help in improving the communication between the pathologist and the treating clinician.

Background: Breast cancer is steadily increasing worldwide. This study is based on application of recently proposed International Academy of cytology (IAC) Yokohama categorisation system of Breast cytology from C1 to C5. (C1-Insufficient material, C2-Benign, C3- Atypical, C4-Suspicious &amp; C5-Malignant). We aim to categorize the breast lesions based on the above-mentioned categorization scheme (IAC, Yokohama 2016) along with histopathological correlation (wherever possible).Materials and Methods: This was a retrospective observational study conducted from January 2018 to December 2021 in the Department of Pathology of a tertiary care hospital involving coastal population. Ethical clearance was taken from institutional reviw committee. All patients with palpable breast lumps who had undergone FNAC were included in the study. Patient details and data were collected from the case records maintained in Department of Pathology. All quantitative parameters were described through descriptive statistics. Total scores were computed for all the risk factors. Sensitivity, specificity, Positive Predictive Value, Negative Predictive Value calculated. Risk of malignancy(ROM) was calculated for each category.Results: A total 200 patients, with age group ranging from 17 - 67 years with breast lesions were included in the study. C1 lesions were found in 5 cases, C2 in 152 cases, C3 in 11 cases, C4 in 4 cases, and C5 in 28 cases. Cytohistological correlation obtained in 94 cases with concordance noted in 89 cases and discordance in 5 cases.Conclusions: Breast FNAC cytology categorization according to IAC Yokohama system increases accuracy of diagnosis and helps clinician in appropriate patient management.

Breast cytology is a significant component of the "Triple approach" for pre-operative diagnosis of breast lumps, the other two being clinical assessment and radiological imaging. The role of Fine needle aspiration cytology (FNAC) as a first line investigation in diagnosing breast lesions is well documented, however histopathology is the gold standard. Cyto-histopathological correlation is of great relevance and also increases precision.AIMS \& OBJECTIVES:The present study was conducted with the aim to categorize breast lesions according to the latest standardized reporting system proposed by International academy of cytologists (IAC) in 2016. Evaluation of diagnostic accuracy, sensitivity and specificity of FNAC in diagnosing breast lesions and cyto-histopathological correlation was planned. All FNAs of breast lesions over a period of 2 years were included in the study. The cases were grouped into five standardized categories proposed by the International academy of cytology: Category I (Insufficient material), Category II (Benign), Category III (Atypical, probably benign), Category IV (Suspicious, probably in situ or invasive) & Category V (Malignant) respectively. Specificity, sensitivity, diagnostic accuracy, negative and positive predictive value of FNAC were calculated and cyto-histopathological correlation assessed wherever possible. Out of 468 breast lesions reported on FNAC, the category wise distribution was - Category I, II, III, IV & V accounting for 23(4.9%), 342(73.07%), 7(1.5%), 11(2.35%) and 85(18.16%) respectively. Histopathology was performed in 331/468 cases with cyto histological concordance of 98.4% and a type agreement rate of 90.9%. The sensitivity, specificity, positive and negative predictive value and diagnostic accuracy was 98.90%, 99.16%, 97.82%, 99.58% and 99.09% respectively. FNAC is a simple, reliable, cost effective, first line diagnostic procedure for all breast lumps. In collaboration with physical examination and imaging studies (triple approach), FNAC is a highly sensitive diagnostic tool. Adopting a universally acceptable standardized reporting system for breast cytology can enhance the diagnostic accuracy of FNAC.

Background: In 2016, the International Academy of Cytology (IAC) established a reporting system for breast fine-needle aspiration (FNA) cytology. This system proposed five categories in its classification: category for insufficient; category 2 for benign; category 3 for atypical, probably benign; category 4 indicating suspicious for malignancy; and category 6 for malignant. Aims and Objectives: The aim of the present study was to review and categorize the breast FNA samples according to the new system of reporting, to assess the risk of malignancy (ROM) for each category, and to assess the diagnostic yield of breast FNA biopsy (FNAB). Materials and Methods: The present retrospective study was conducted in the department of pathology, IGMC, Shimla from January 2019 to December 2019. All the samples during this period were included in the study. Results: A total of 405 breast cytology cases were included in the present study. The FNA findings were correlated with histopathology in 82 cases. The ROM for each category was 16.6% for insufficient, 3.7% for benign, 0% for atypical for malignancy, 100% for suspicious for malignancy, and 92.3% for malignant category. Conclusion: The IAC Yokohama system for reporting breast FNA cytology helps in standardizing reports and easier communication of the pathologists with treating surgeons. It offers a ROM for each category which helps during follow-up of patients. Utilizing the system in day-to-day reporting will improve diagnostic clarity and management.

The International Academy of Cytology (IAC) Yokohama System has developed a standardized system of reporting breast cytology. The current study aimed to apply the newly proposed YOKOHAMA classification system along with American College of Radiology Breast Imaging Reporting and Data system (ACR-BI-RADS) scoring to breast fine-needle aspiration cytology (FNAC) cases from the department archives and to assess the risk of malignancy (ROM) for each category. All breast FNACs done between January 20017 and June 2023 were reclassified according to the proposed IAC Yokohama reporting system. Histopathological correlation of the IAC Yokohama system and BI-RADS was done wherever available. A three-category approach was followed based on benign versus malignant, and sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated using histopathology as the gold standard. A total of 2130 breast FNACs were performed, of which 469 had a histopathological correlation and 892 had a BI-RADS correlation. The ROM for insufficient, benign, atypical, suspicious, and malignant categories were 29.16%, 3.28%, 28.57%, 100%, and 92.18%, respectively. Maximum specificity (96.8%) was observed when only malignant (cat A) and when both suspicious and malignant cases (Cat B) were taken as positive test results. Highest sensitivity (92.7%) was achieved when atypical, suspicious, and malignant cases were taken as positive test results (Cat C) and highest diagnostic accuracy (94.8%) was seen in category B. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy of BI-ADS were 78.67%, 92%, 85.5%, 87.8%, and 87%, respectively. FNAC and imaging are the key modalities for diagnosing breast lesions. The IAC Yokohama system along with ACR-BI-RADS provides a simple yet useful approach for effectively categorizing the different breast lesions, which is useful for patient management and risk stratification.

Introduction:Recently the International Academy of Cytology (IAC) proposed a new Yokahama reporting system for breast fine-needle aspiration cytology (2019) in order to standardize reporting pattern and to link cytology reporting to management algorithms.Aims and Objectives:To categorize the samples according to the newly proposed IAC Yokahama reporting system of breast cytology and to assess diagnostic accuracy and corresponding risk of malignancy (ROM) for each category.Materials and Methods:This is a retrospective study of breast cytology cases done at Department of Pathology. The slides are retrieved from pathology archives and classified using a recently proposed IAC, Yokahama reporting system of breast cytology into five categories. The risk of malignancy, sensitivity, specificity, and diagnostic accuracy were estimated on the basis of the final histopathological diagnosis.Results:Of the 386 cases of breast FNAC, 226 (55.55%) had the corresponding histological diagnosis. The respective ROM for each category was 22.22% for category 1 (insufficient material), 5.32% for category 2 (benign), 26.31% for category 3 (atypical), 100% for category 4 (suspicious for malignancy), and 100 % category 5 (malignant). Malignant cases were considered only when positive tests, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 89.66%, 100%, 100%, 90.2%, and 94.69%, respectively.Conclusions:The present study showed statistically significant sensitivity, specificity, and diagnostic accuracy, especially with malignant cases. Hence, using the IAC Yokahama reporting system of breast cytology is effective to standardize the reporting in various institutes and provide clear guidelines to clinician for further management.

Introduction: Breast cancer is rapidly emerging as the leading cause of cancer in Indian women. Cytopathology and histopathology services are required to tackle this growing burden. The use of International Academy of Cytology (IAC) Yokohama Reporting System of breast cytology by classifying them into five categories insufficient, benign, atypical, suspicious and malignant. (IAC) Yokohama Reporting System offers structured protocols, are expected to improve breast cytopathology reporting. Objective : The main objectives of our study were to classify breast fine needle aspirates according to the IAC Yokohama system and assess the risk of malignancy, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. Methodology: All breast FNAs done in the above period were retrieved and classified into five categories according to the Yokohama system. Histopathological diagnosis was also retrieved wherever available. Results: The new “International Academy of Cytology (IAC) Yokohama system” was used to categorize 205 patients into five categories based on the cytologic diagnosis. That C1: insucient material (7.8%), C2: benign (64.3%), C3: atypical (7.3%), C4: suspicious of malignancy (7.8%), and C5: malignant (12.6%). Risk of malignancy (ROM) was calculated which was 100% in Yokohama category I, IV and V. In category II ROM was 00% and in category III ROM was 55.5%. FNAC correlation with histopathology was significant (P Value=&lt;0.01 &amp; Chi square value 40.7). Conclusion: The IAC Yokohama system is an excellent system for accurately diagnosing breast fine needle aspirate. Keywords: Histopathology, International Academy of Cytology Yokohama System, Fine­ Needle Aspiration Biopsy Cytopathology

Background: Worldwide breast malignancy is the major cause for mortality among women. Screening and early detection are crucial. Grey zones of uncertainty in cytomorphological differentiation of benign from malignant lesions can be overcome by Yokohama system of classification. Aims and Objectives: The objectives of this study are as follows: (1) To categorize Breast fine needle aspiration cytology (FNAC) samples according to the international academy of cytology (IAC) Yokohama system. (2) To assess the diagnostic accuracy, sensitivity, specificity, and risk of malignancy (ROM) for each category. Materials and Methods: A retrospective study of 144 breast FNAC cases with histopathological diagnosis was done based on Yokohama System from January 2018 to December 2020. ROM in each category was calculated. The study results were analyzed for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) considering histological diagnosis as the gold standard. Results: Recategorization of 144 cases with histopathological diagnosis was done according to Yokohama system as insufficient material, benign, atypical, suspicious for malignancy, and malignant. The respective ROM for each category was, 7.6% for Category-1 (Insufficient), 15.26% for Category-2 (Benign), 65.38% for Category-3 (Atypical), 83.33% for Category-4 (Suspicious), and 99.18% for Category-5 (Malignant). Considering malignant cases as positive, sensitivity – 86.75%, specificity – 97.32%, PPV – 99.19%, NPV – 66.06%, and accuracy of 88.96% were deduced. Conclusion: Incorporation of IAC Yokohama system to categorize breast cytopathology using uniform terminologies provides diagnostic clarity, consistency, and accuracy in reporting, which in turn helps the clinician to predict the ROM and patient outcome.

Background: Worldwide breast malignancy is the major cause for mortality among women. Screening and early detection are crucial. Grey zones of uncertainty in cytomorphological differentiation of benign from malignant lesions can be overcome by Yokohama system of classification. Aims and Objectives: The objectives of this study are as follows: (1) To categorize Breast fine needle aspiration cytology (FNAC) samples according to the international academy of cytology (IAC) Yokohama system. (2) To assess the diagnostic accuracy, sensitivity, specificity, and risk of malignancy (ROM) for each category. Materials and Methods: A retrospective study of 144 breast FNAC cases with histopathological diagnosis was done based on Yokohama System from January 2018 to December 2020. ROM in each category was calculated. The study results were analyzed for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) considering histological diagnosis as the gold standard. Results: Recategorization of 144 cases with histopathological diagnosis was done according to Yokohama system as insufficient material, benign, atypical, suspicious for malignancy, and malignant. The respective ROM for each category was, 7.6% for Category-1 (Insufficient), 15.26% for Category-2 (Benign), 65.38% for Category-3 (Atypical), 83.33% for Category-4 (Suspicious), and 99.18% for Category-5 (Malignant). Considering malignant cases as positive, sensitivity – 86.75%, specificity – 97.32%, PPV – 99.19%, NPV – 66.06%, and accuracy of 88.96% were deduced. Conclusion: Incorporation of IAC Yokohama system to categorize breast cytopathology using uniform terminologies provides diagnostic clarity, consistency, and accuracy in reporting, which in turn helps the clinician to predict the ROM and patient outcome.

Background: To keep uniformity and to achieve standardization of thyroid cytopathology reporting National Cancer Institute proposed six tier diagnostic classification system named The Bethesda system for reporting thyroid cytopathology (TBSRTC) that represents a major step toward standardization, reproducibility, and ultimately improved clinical significance, usefulness, and predictive value of thyroid Fine-needle aspiration cytology (FNAC). The guidelines were formulated in 2007 and revised in 2017. Material and Methods: The present study was performed at between January 2015 and June 2019, on thyroid FNA classifying them according to TBSRTC. Cytology and histopathology correlation were done where ever available. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of TBSRTC were calculated considering histopathology as gold standard. The malignancy risk for each category was calculated and the result was tabulated. Results: In the present study, total of 1248 cytology cases of thyroid were studied, out of them 1% were non diagnostic, 91.3% were benign, 1.5% were atypical lesions of undetermined significance (AUS). About 4% were follicular neoplasm (FN), 0.4 was suspicious for malignancy (SM), and 1.8% were malignant. A total of 179 cases were available for cytology and histopathology correlation and risk of malignancy (ROM) was calculated. No histopathology cases were available in category I for correlation, ROM was 4.7% in benign category, 46.2% in AUS category, 50% in SFN/FN, 100% in SM, and 85.7% in malignant category. TBSRTC showed sensitivity of 66.7%, specificity of 90.9%, PPV of 64.8%, NPV of 91.5%, and accuracy of 86.03%. Conclusion: TBSRTC improves perceptions of diagnostic terminology between cytopathologists and clinicians, prevent over diagnosis and helps in better patient management approaches. It should be included in all FNAC of thyroid reporting system.