The International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology: A Single Institutional Retrospective Study of the Application of the System Categories and the Impact of Rapid Onsite Evaluation

Challenging the concept of "risk of malignancy" in cytology

Several standardized systems for nongynecological cytopathology have been published following the successful implementation of The Bethesda System for Reporting Cervical Cytology. Each of these systems comprises a set of reporting categories accompanied by a risk of malignancy. However, in most cases, these risk of malignancy estimates have not been based on high-quality evidence and often may not be consider proper "risks" (because they have been estimated based on cross-sectional studies). This commentary discusses the problems related to the data used to generate these risks. To make nongynecological cytopathology reporting more evidence-based, large-scale prospective cohort studies and randomized trials, in addition to high-quality systematic reviews and meta-analyses, should be performed.

Interobserver agreement and risk of malignancy using the International Academy of Cytology Yokohama System for reporting breast FNA biopsy in a liquid-based exclusive cohort

BACKGROUND

Per the College of American Pathologist's National Breast Fine Needle Aspiration Biopsy (FNAB) Practice Survey, ∼40% of laboratories use liquid-based cytology (LBC) for breast FNAB. The reproducibility of the International Academy of Cytology Yokohama System (YS) for reporting breast FNAB on LBC was explored.

DESIGN

Breast FNAB specimens submitted as LBC only (all ThinPrep) between January 2017 and January 2021 were retrieved. Cases without histopathologic follow-up were excluded. Clinical and radiologic information was collected. One cytologist and six cytopathologists rendered diagnoses per YS. All reviewers were blinded to the original diagnosis and histopathologic follow-up. The risk of malignancy was calculated. Concordance rates were calculated by a weighted Cohen Kappa score (κ).

RESULTS

Review of 110 cases demonstrated substantial to near-perfect agreement between each reviewer (κ = 0.73-0.91) and follow-up histopathology (κ = 0.66-0.85). The agreement was lowest in the inadequate (κ = 0.05) and atypical (κ = 0.04) categories. The lack of concordance in the atypical category was common in cases with low cellularity or incomplete structural features. The risk of malignancy for inadequate, benign, atypical, suspicious for malignancy, and malignant categories were 12.5% (2/16), 3% (2/65), 67%, (8/12) 100% (1/1), and 100% (16/16).

CONCLUSION

Interobserver agreement is excellent using the five YS categories in LBC. Lack of cellularity and incomplete architectural features were barriers to perfect agreement. Established pitfalls in the interpretation of LBC were cause for atypical diagnoses. Continuous training and education are recommended to avoid misdiagnosis because of the nonconventional cytomorphologic features of LBC and to improve inadequate and atypical rates within YS.

Assessing the accuracy of the International Academy of Cytology Yokohama System for reporting breast fine needle aspiration biopsy cytology at a Vietnamese oncology centre

BACKGROUND

Fine needle aspiration biopsy (FNAB), accompanied by classification systems for cytology, can offer a cheap and convenient option for the diagnosis of breast cancer in women with suspicious breast lumps. In this study, we aimed to assess the accuracy of the International Academy of Cytology (IAC) Yokohama system in a Vietnamese oncology centre.

METHODS

A retrospective cross-sectional study was conducted from November 2021 to April 2022 at Vietnam National Cancer Hospital. We included patients with full hospital records regarding breast lesions for which FNAB was indicated. A total of 803 patients' FNAB specimens were assessed according to the IAC Yokohama system. The basic characteristics were summarised using the appropriate summary measurements. The risk of malignancy (ROM) was calculated for each classification category.

RESULTS

The median age was 42.7 years (range: 14-85). The mean size of the lesions was 17.9 mm (range: 4-123 mm). We had 215 histopathological reports. The most common benign and malignant diagnoses were fibroadenoma and invasive carcinoma, respectively. The ROM for categories II, III, IV, and V was calculated as 3.4%, 37.5%, 95%, and 99.2% respectively. The sensitivity, specificity, positive predictive value, and negative predictive value were 96.4%, 97.2%, 98.5%, and 93.2%, respectively.

CONCLUSION

The IAC Yokohama system offers a good option with which to predict underlying breast pathology using a simple and cheap procedure. However, pathologists require continuous training to ensure accurate interpretation of the slides.

Neoadjuvant Therapy in Nonmetastatic Breast Cancer in Kurdistan, Iraq

PURPOSE

The core management of nonmetastatic breast cancer includes surgical tumor removal by either breast-conserving surgery (BCS) or mastectomy. The use of neoadjuvant chemotherapy (NACT) has shown the potential to downstage locally advanced breast cancer (LABC) and reduce the extent of breast or axillary surgery. This study aimed to assess the treatment approach for nonmetastatic breast cancer in the Kurdistan region of Iraq and to compare its alignment with the current international recommendations for cancer treatment.

METHODS

We retrospectively reviewed the records of 1,000 patients with prespecified eligible inclusion criteria who underwent either BCS or mastectomy for nonmetastatic invasive breast cancer at oncology centers in the Kurdistan region of Iraq between the period 2016 and 2021.

RESULTS

Of 1,000 patients (median age, 47 years [range, 22-85 years]), 60.2% underwent mastectomy and 39.8% underwent BCS. The proportion of patients treated with NACT has increased over time, with 8.3% of patients receiving neoadjuvant treatment in 2016 compared with 14.2% in 2021. Similarly, BCS increased from 36.3% in 2016 to 43.7% in 2021. Most patients who underwent BCS had early breast cancer with low nodal involvement burden.

CONCLUSION

The increasing trends of BCS practice in LABC along with the increased use of NACT in the Kurdistan region in recent years comply with international guidelines. Our large multicenter, real-life series emphasizes the need to implement and discuss more conservative surgical approaches, enhanced with the broader use of NACT, through education and information programs for health providers and patients, in the context of multidisciplinary team discussions, to deliver high-quality, patient-centric breast cancer care.

The Use of the International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy

OBJECTIVES

To perform the first meta-analysis regarding the pooled risk of malignancy (ROM) of each category of the Yokohama system for reporting breast fine-needle aspiration, as well as assess the latter's diagnostic accuracy using this new system.

METHODS

Two databases were searched, followed by data extraction, study quality assessment, and statistical analysis.

RESULTS

The "Insufficient," "Benign," "Atypical," "Suspicious," and "Malignant" Yokohama system categories were associated with a pooled ROM of 17% (95% CI, 10%-28%), 1% (95% CI, 1%-3%), 20% (95% CI, 17%-23%), 86% (95% CI, 79%-92%), and 100% (95% CI, 99%-100%), respectively. When both "Suspicious" and "Malignant" interpretations were regarded as cytologically positive, sensitivity (SN) was 91% (95% CI, 87.6%-93.5%) and false-positive rate (FPR) was 2.33% (95% CI, 1.30-4.14%). A summary receiver operating characteristic curve was constructed and the pooled area under the curve was 97.3%, while the pooled diagnostic odds ratio was 564 (95% CI, 264-1,206), indicating a high level of diagnostic accuracy. When only "Malignant" interpretations were regarded as cytologically positive, the pooled FPR was lower (0.75%; 95% CI, .39%-1.42%) but at the expense of SN (76.61%; 95% CI, 70.05%-82.10%).

CONCLUSIONS

Despite Yokohama's system early success, more data would be needed to unravel the system's value in clinical practice.

Performance of breast fine needle aspiration as an initial diagnostic tool: A large academic hospital experience

BACKGROUND

The clinical performance of the Yokohama reporting system for breast cytology remains uncertain.

METHODS

In this study, we retrospectively evaluated 318 breast fine needle aspirations (FNABs) from Los Angeles County Hospital over a five-year period, analysing data for breast cytology, histology, and radiology.

RESULTS

Among 318 breast FNAB cases, 78.3% (249/318) were benign and 5.3% (17/318) malignant. Of 83 cases with follow-up histology, 14.5% (12/83) were insufficient, 66.3% (55/83) were benign, and 16.9% (17/83) were malignant. Of 55 benign cases, 61.8% (34/55) were fibroadenoma and 9 (9/55, 16.4%) were fibrocystic changes. Two cases were diagnosed as "atypical" but confirmed "benign" on core needle biopsy (CNB). No "suspicious" cases were found. Seventeen malignant cases were confirmed by CNB, including 70.6% (12/17) invasive ductal carcinoma, 11.8% (2/17) invasive lobular carcinoma, and one malignant phyllodes tumour. Receptor studies on cell blocks of three malignant cases showed concordant results with CNB results. In addition, 82.2% (148/180) of lesions with Breast Imaging-Reporting and Data System (BI-RADS) scores of 2 or 3 were benign and 92.3% (12/13) BI-RADS score 5 lesions were malignant on FNAB. Finally, 90% (67/74) of BI-RADS 4a lesions were benign, and 97% (36/37) of fibroadenomas were BI-RADS score 4a.

CONCLUSION

This, by far the largest U.S. breast cytology study, showed 93.3% sensitivity, 100% specificity, 100% positive predictive value, and 98.2% negative predictive value for breast FNAB. Women with breast lesions of BI-RADS score 3 or less have a low risk of malignancy; FNAB would contribute to the reduction of excisional biopsies. FNAB can be considered as an initial diagnostic tool for BI-RADS 4 mass/lesions and satellite lesions, as well as for triaging patients.

The Value of Fine Needle Aspiration Biopsy in the Pre-Operative Assessment of the Axilla in Breast Cancer Patients

This paper reviews the role of fine needle aspiration biopsy (FNAB) in assessing the axilla prior to definitive surgery or neoadjuvant therapy in breast cancer patients. The radiological criteria for biopsy are discussed and pathological techniques and pitfalls illustrated. The sensitivity and specificity of the technique and the clinical utility are addressed, with particular reference to the current controversies in the management of the axilla in the light of the American College of Surgeons Oncology Group Z0011 trial results. The low morbidity procedure of FNAB is recommended when the radiological and clinical features suggest a high yield from the abnormal axillary nodes, with consideration of core biopsy if an expected positive result is not obtained or the circumstances require tissue for ancillary studies. In conclusion, FNAB of the axilla is a highly sensitive procedure which can offer further valuable information to assist in clinical decision making. The technique is of particular value in the setting of a large primary tumour size and multiple enlarged nodes. A summary flow chart is provided to facilitate pre-operative management of the axilla and to encourage a universal approach.

Risk of Malignancy in Breast FNAB Categories, Classified According to the Newly Proposed International Academy of Cytology (IAC) Yokohama System

Background

A new category system comprising five classes (C1-insufficient material, C2-benign, C3-atypical, C4-suspicious, and C5-malignant) has been proposed by the International Academy of Cytology (IAC) for fine needle aspiration biopsy cytology (FNAB) for proper diagnosis of breast cancer.

Aims and Objectives

This study is designed to categorize institutional FNAB data according to the new system and calculation of the absolute risk of malignancy (ROM), sensitivity, specificity, positive predictive values, false negative and false-positive rate.

Study Design

We conducted a retrospective cross-sectional study involving 2133 cases collected between June, 2008 and August, 2019, at Foundation University Medical College’s Department of Histopathology and the Surgery and Oncology Department at the Fauji Foundation Hospital. All cases fulfilling the inclusion and exclusion criteria were retrieved from the archives and reviewed by two expert pathologists. Matching histopathology was compared with the cytology reports for concordance or discordance of results.

Findings

We found 6.9% (n = 147) insufficient, 65.8% (n = 1403) benign, 7.2% (n = 153) atypical, 7.5% (n = 160) suspicious and 12.6% (n = 270) malignant cases. Cyto-histological correlation was found in 421 cases from the year 2014 to 2019 with 370 concordant and 51 discordant cases. The maximum number of concordant cases was 151 in the C5 category and discordant cases had a diagnosis of C3 and C4 on cytology with 16 cases in each category. The calculated values of ROM were 45.45%, 10.3%, 30.6%, 82.79% and 99.34% from C1 to C5, respectively. We calculated 83.42% absolute sensitivity and 85.24% specificity. The positive predictive value for category 3, 4 and 5 was 67.34%, 82.7% and 99.34%, respectively, while false-negative rate was 7.9% and false-positive rate was 0.66%.

Conclusion

The ROM for C1 category calculated from this study is quite high (45.45%) compared to previous studies; therefore, it is recommended to perform core needle biopsy in all these cases. The higher sensitivity and specificity of this method of diagnosing malignant lesions supports its use.

The International Academy of Cytology standardized reporting of breast fine-needle aspiration biopsy cytology: A 2 year's retrospective study with application of categories and their assessment for risk of malignancy

Objectives

Breast cancer is the most common cancer in women worldwide. The fine-needle aspiration biopsy (FNAB) may be used as the first-line pathological investigation for evaluation and early diagnosis of the breast lesion. The FNAB helps to differentiate malignant from benign lesions. In the present study, we categorized the breast FNAB cases according to the International Academy of Cytology Yokohama System (IACYS) for reporting breast FNAB cytology and to assess the risk of malignancy (ROM) for each category.

Material and Methods

A retrospective data of breast lesions were retrieved from the archives of pathology department between January 2018 and December 2019. The study got approval from the Institutional Ethics Committee. Only 123 cases with cytology and histopathological correlation were included in this study. The cytological category was given according to IACYS for reporting breast FNAB cytology.

Results

The FNAB results were include as insufficient material 3.25% (4/123), benign 46.34% (57/123), atypical 12.2% (15/123), suspicious for malignancy (SM) 4.88% (6/123), and malignant 33.33% (41/123). The ROM was 50%, 7.27%, 40.0%, 83.33%, and 97.5% for NS, benign, atypical, SM, and malignant, respectively.

Conclusion

FNAB is an important tool in the diagnosis and management of breast lesions, especially in financial constrained developing countries like India with limited resources, where practice of core needle biopsy is limited. The 5-tier IACYS for reporting breast FNAB improves the reproducibility of cytology reports across the world and helps in triaging the breast lesion patients.

The role of the IAC Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy and the ACR Breast Imaging-Reporting and Data System in the evaluation of breast lesions

BACKGROUND

Stratification of breast lesions for appropriate management is achieved through an integration of clinical examination, imaging, and fine needle aspiration biopsy (FNAB). The current study aimed to evaluate the combined effectiveness of the widely used Breast Imaging-Reporting and Data System (BI-RADS) with the recently proposed International Academy of Cytology (IAC) Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology.

METHODS

A retrospective analysis was done on all breast FNABs from 2016 through 2020. The cases were categorised according to the IAC Yokohama System. Histopathological correlation of the BI-RADS and IAC Yokohama System was performed. The rate of malignancy (ROM) for each category of the BI-RADS and IAC Yokohama System was calculated.

RESULTS

The ROM values for categories I to V were 38%, 0.6%, 21.9%, 100%, and 97%, respectively. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of FNAB with category III assumed as malignant were 98.9%, 85%, 76.1%, 99.3%, and 89.5%, respectively. With category III assumed as benign, these indices were 90.8%, 98.9%, 97.5%, 95.7%, and 96.2%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of BI-RADS were 91.5%, 81.9%, 72%, 95%, and 85.1%, respectively.

CONCLUSIONS

FNAB is still an indispensable test in the evaluation of breast lesions. The utilisation of the IAC Yokohama reporting system for breast cytology in conjunction with ACR BI-RADS aids in better stratification of lesions.

Categorization of Breast Fine Needle Aspirates Using the International Academy of Cytology Yokohama System Along with Assessment of Risk of Malignancy and Diagnostic Accuracy in a Tertiary Care Centre

Context:

The International Academy of Cytology Yokohama System has developed a standardized system of reporting breast cytology by classifying them into five categories – insufficient, benign, atypical, suspicious, and malignant. Numerous studies conducted at different centers are required to confirm the risk of malignancy of the different categories.

Aims:

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.

Settings and Design:

It was a retrospective study done over a period of 2 years from January 2018 to December 2020.

Materials and Methods:

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.

Statistical Analysis Used:

Using a histopathological diagnosis as the gold standard, sensitivity, specificity, PPV, NPV, and diagnostic accuracy were calculated. For each of the five categories, the risk of malignancy was also assessed.

Results:

Out of the 554 breast fine needle aspirates, 242 had histopathological correlation. The risk of malignancy for insufficient, benign, atypical, suspicious, and malignant categories were 5%, 1.5%, 17.4%, 81.8%, and 100%, respectively. Maximum sensitivity (97.2%) was achieved when atypical, suspicious, and malignant cases were considered as positive test results. The highest specificity (100%) was observed when only malignant cases were considered as positive test results, whereas maximum diagnostic accuracy (96.4%) was noted when the malignant and suspicious category was included in positive test results.

Conclusion:

The IAC Yokohama system is an excellent system for accurately diagnosing breast fine needle aspirates with greater reproducibility of reports and better communication between the pathologist and clinician.

Performance of Rapid On-Site Evaluation in Breast Fine-Needle Aspiration Biopsies: Identifying Areas of Diagnostic Challenge

INTRODUCTION

Fine-needle aspiration (FNA) is a well-established method for sampling breast lesions with high accuracy and positive predictive value. Despite its decline in recent years relative to the use of core needle biopsies, there are several advantages to FNA which include cost-effectiveness, low complication rate, and the ability to perform rapid on-site evaluation (ROSE). The aim of this study was to evaluate breast FNAs with ROSE to identify diagnostic challenges during ROSE.

MATERIALS AND METHODS

We identified all breast FNAs with ROSE performed at Massachusetts General Hospital from January 2014 to December 2019. From the electronic medical record, clinical, radiological, and follow-up pathology results were recorded. Comparison between the rapid and final cytological diagnosis was made. All discrepancies were documented with major discrepancy defined as a malignant rapid interpretation not confirmed on final diagnosis or a negative rapid interpretation upgraded to suspicious or positive on final diagnosis.

RESULTS

The study cohort consisted of 483 breast FNAs with ROSE. The rapid and final cytological interpretations showed good correlation, with only 6 (1.2%) major discrepancies. Problematic areas included low-grade, lobular, and fibroepithelial lesions with low cellularity being a contributory factor to misclassification.

CONCLUSIONS

FNA remains a highly accurate method for the evaluation of breast lesions with ROSE.

Fine-Needle Aspiration Biopsy Cytopathology of Breast Lesions Using the International Academy of Cytology Yokohama System and Rapid On-Site Evaluation: A Single-Institute Experience

INTRODUCTION

Breast cancer is rapidly emerging as the leading cause of cancer in Indian women. Robust cytopathology and histopathology services are required to tackle this growing burden. The use of rapid on-site evaluation (ROSE) and the International Academy of Cytology (IAC) Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy (FNAB) Cytopathology, which offers structured protocols, are expected to improve breast cytopathology reporting.

METHODS

We retrieved the cytopathology slides, categorized them by the IAC Yokohama System and histopathology data of all the patients who had been investigated for breast lesions from September 2016 to December 2018, and compared the cytopathology and histopathology. Risk of malignancy (ROM) and performance metrics, like sensitivity, specificity, predictive values, accuracy, and area under the curve were computed.

RESULTS

A total of 1,147 FNABs were evaluated, of which 442 (38.5%) underwent ROSE and 624 (54.4%) histopathology. Reported using IAC categories, our cohort recorded 4.9% inadequate, 65.3% benign, 7.8% atypical, 3.3% suspicious for malignancy, and 18.7% malignant lesions. The overall sensitivity and specificity for identifying in situ and malignant lesions were 99.1% and 99.3%, respectively, and were substantially improved by ROSE. ROSE improved the concordance between cytopathology and histopathology from 76.9% to 90.2%, by reducing inadequate (p < 0.001) cases. The ROM increased along a gradient from inadequate to malignant categories, with the gradient being sharpened by ROSE. The false negativity rate was 0.7% and false positivity rate 0%.

CONCLUSION

Incorporating ROSE and the IAC Yokohama System for breast cytopathology reporting improves accurate diagnosis of breast lesions, prevents missed diagnoses, and provides reliable estimates of ROM. These protocols also aid in standardizing a reproducible system for monitoring and auditing of breast pathology services, identify areas that need strengthening, and improve training at pathology centers.

The International Academy of Cytology Yokohama System for Reporting Breast Cytopathology showed improved diagnostic accuracy

BACKGROUND

The aim of the International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology is to improve cytology practice. This study assessed cytologic diagnoses made with the system and its efficacy when it was applied by pathologists with different levels of experience.

METHODS

In all, 1080 cases of breast fine-needle aspiration biopsy (FNAB) over a period of 16 years were reviewed and reclassified with the system. The category distribution and the diagnostic performance were compared with the original diagnoses. The concordance rates for diagnoses from pathologists with different levels of experience were also determined.

RESULTS

The distribution of cytologic diagnoses made with the system was as follows: 11.7% were insufficient, 56.6% were benign, 20.1% were atypical, 6.1% were suspicious for malignancy, and 5.6% were malignant. The rates for the insufficient and atypical categories were lower than the original diagnosis rates (13.1% and 23.8%, respectively). Overall, 120 cases (11.1%) were recategorized. Among those recategorized as benign, suspicious, or malignant with follow-up data, 96.7% were correctly reclassified. A significant improvement in diagnostic performance was found with the system (P < .001). Such improvement was also seen in problematic breast lesions, including fibroepithelial lesions, papillary lesions, and low-grade carcinomas. Pathologists with intermediate experience showed a higher concordance with an expert pathologist in the diagnoses than those with short experience (κ, 0.838 vs 0.634).

CONCLUSIONS

The system effectively categorized the diagnoses, and the diagnostic performance of FNAB reporting was improved. The structured reporting also enhanced the reproducibility of reporting by pathologists with intermediate experience and, to some extent, those with short experience.

Effectuation of International Academy of Cytology Yokahama Reporting System of Breast Cytology to Assess Malignancy Risk and Accuracy

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.

Accuracy of Breast Fine-Needle Aspiration Biopsy Using the International Academy of Cytology Yokohama System in Clinico-Radiologically Indeterminate Lesions: Initial Findings Demonstrating Value in Lesions of Low Suspicion of Malignancy

BACKGROUND

Fine-needle aspiration biopsy (FNAB) in breast lesions offers accurate results in differentiating benign and malignant lesions. However, its role is unclear when core-needle biopsy (CNB) is available, the latter providing additional information regarding tumor grade, invasion, and hormone receptor status in malignant lesions. In benign breast lesions, especially in BIRADS category 4a and 4b, FNAB, and CNB provide similar pathological information, whereby FNAB may serve as a more rapid and cost-effective investigation. The study was planned to reevaluate the diagnostic accuracy of FNAB in BIRADS category 4a, 4b, and 4c lesions.

MATERIALS AND METHODS

FNAB and biopsy reports of all patients with breast lesions sent between September 1, 2018, and November 30, 2020, were collected and the International Academy of Cytology (IAC) Yokohama category and BIRADS score were recorded for each case. The rate of malignancy and the accuracy of FNAB in diagnosing malignancy were calculated for each BIRADS 4a, 4b, and 4c subgroup.

RESULTS

A total of 249 cases of BIRADS 4 lesions had corresponding cytology and histopathology diagnoses. FNAB showed high diagnostic accuracy in all BIRADS groups. A benign categorization was associated with a very low number of false-negative diagnoses, especially in BIRADS 4a lesions.

CONCLUSION

The study reconfirms the excellent accuracy of breast FNAB using the IAC Yokohama system in diagnosing breast malignancies. Furthermore, BIRADS 4a lesions found to be belonging to the cytological benign category may be excluded from CRB and kept on clinical follow-up.

Prospective evaluation of accuracy of fine-needle aspiration biopsy for breast lesions using the International Academy of Cytology Yokohama System for reporting breast cytopathology

BACKGROUND

Classification of breast lesions into different cytological groups can accurately be done using the International Academy of Cytology (IAC) Yokohama System for reporting breast cytopathology. Fine needle aspiration biopsy (FNAB) of breast lesions has been considered to be the primary investigation in detecting breast cancers, especially in low-cost settings. The main objective of this study was to prospectively re-confirm the diagnostic accuracy of breast FNAB using the IAC Yokohama system. Additionally, separate secondary subgroup analysis was done to confirm the accuracy of breast FNAB excluding lymph-node positive and lymphadenopathy positive tumors.

MATERIAL AND METHODS

A prospective study was done on patients undergoing biopsy of breast lesions between September 01, 2019 and November 30, 2020 (519 biopsies on 487 unique patients). Of these 519 histopathology biopsies, 505 had corresponding FNAB report of the same site. The FNAB was reported using the IAC Yokohama system and the most suitable category was allotted in every case. The rates of malignancy for each category and the accuracy of breast FNAB in diagnosing malignancy were calculated.

RESULTS

Of the total 487 patients, 120 cases were benign on histology, while 367 were malignant. The rates of malignancy in benign, atypical, suspicious and malignant categories were 5%, 25%, 71%, and 99.7%, respectively. The diagnostic accuracy of atypical, suspicious and malignant categories was calculated as 90.1%, 95.2%, and 93.3%, respectively.

CONCLUSION

The high diagnostic accuracy for each BIRADS category suggest excellent accuracy for Breast FNAB using the IAC Yokohama system.

Implementation of the International Academy of Cytology Yokohama standardized reporting for breast cytopathology: An 8-year retrospective study

BACKGROUND

The International Academy of Cytology (IAC) Yokohama reporting system was recently proposed to serve as a standardized diagnostic platform for the cytological interpretation of breast fine needle aspiration biopsy (FNAB). Five cytological categories were suggested, linked to a certain risk of malignancy (ROM). The aim of this study was to assess the potency of this newly proposed reporting guideline, with a review of literatures.

METHODS

This is a retrospective study over 8-year duration in which all the breast FNABs performed in our institution were recategorized in accordance to the IAC Yokohama reporting system. Kappa coefficient was used to evaluate the agreement between the proposed cytological category and corresponding histological diagnosis, with the level of significance set at 5%. Cyto-histopathological correlation and its diagnostic performance were also assessed.

RESULTS

A total of 1136 breast FNABs were analyzed, including 31 repeat FNABs. Of these, 521 (47.1%) cases had matched histopathological results. Respective ROM for each category was: "insufficient" 13.6%, "benign" 0.4%, "atypical" 25.0%, "suspicious" 85.7%, and "malignant" 100%. There was substantial agreement (κ=0.757) between cytology and histopathological results. Our data revealed a high-diagnostic specificity, sensitivity, positive and negative predictive value of 99.3% (95% CI: 97.6%-99.9%), 94.2% (95% CI: 87.9%-97.9%), 98.0% (95% CI: 92.5%-99.5%), 98.0% (95% CI: 96.1%-99.1%) respectively when both the "suspicious" and "malignant" cases were considered as positive tests, with area under the curve of 0.993.

CONCLUSIONS

The IAC Yokohama system is a reliable, evidence-based, and standardized reporting system that helps to facilitate communication among cytopathologists, radiologists, and surgeons toward individualized patient management.

The International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology: Analysis and discussion of the response to a web-based survey

BACKGROUND

A group of international experts in breast fine needle aspiration biopsy (FNAB) cytopathology, supported by the International Academy of Cytology (IAC), drafted a comprehensive system for reporting breast FNAB cytopathology in 2017-2018. The editorial team produced a survey to assess the international response to the proposed category structure, definitions, and management recommendations in this draft.

METHODS

A web-based survey of 186 questions was generated using the Qualtrics software package (Provo, Utah) supported by the Division of Information Technology at the University of Wisconsin-Madison. The survey was advertised widely-including through the IAC, American Society of Cytopathology, Japanese Society of Clinical Cytology, Papanicolaou Society of Cytopathology, and Australian Society of Cytology and to audiences at national and international meetings-and was available from April to June 2018. The data obtained from the 265 respondents was assessed by the editorial team.

RESULTS

The survey provided a snapshot of the current role and use of breast FNAB and the international variations. Demographic questions were followed by specific questions based on the draft category definitions and statements and focused on issues that had generated discussion among the authors, including the FNAB diagnosis of ductal carcinoma in situ.

CONCLUSION

The survey results strongly supported the development of the IAC Yokohama System and informed subsequent discussions among the authors regarding the final text.

Breast Fine-Needle Aspiration Practice in 2019: Results of a College of American Pathologists National Survey

CONTEXT.—

The College of American Pathologists surveys provide national benchmarks of pathology practice for laboratories.

OBJECTIVE.—

To investigate breast fine-needle aspiration (FNA) biopsy practice in domestic and international laboratories in 2019.

DESIGN.—

We analyzed data from the College of American Pathologists Breast FNA Practice Supplemental Questionnaire that was distributed to laboratories participating in the 2019 College of American Pathologists Non-Gynecologic Cytopathology Education Program.

RESULTS.—

Sixty-one percent (499 of 816) of respondent laboratories routinely evaluated breast FNAs. Cystic lesions were the most common indication, and radiologists primarily performed FNAs in most settings. Forty-five percent (220 of 491) of laboratories performed ancillary studies on breast FNA samples, but 33.8% (70 of 207) did not report fixation time for breast biomarker studies. Only 54.5% (271 of 497) of laboratories had a standardized reporting system and only 16.8% (82 of 488) were aware of the International Academy of Cytology Yokohama Breast FNA Biopsy Cytology Reporting System. There were significant differences among different types of institutions in several aspects of breast FNA practice, including frequency of concurrent FNA and core needle biopsy for the same lesion, primary personnel who performed the FNA, etc. Significant differences existed between domestic and international laboratories in slide preparation, ancillary studies, fixation time reporting, standardized/descriptive diagnosis, and International Academy of Cytology Yokohama Reporting System awareness.

CONCLUSIONS.—

This is the first survey from the College of American Pathologists Cytopathology Committee to investigate breast FNA practices. The data reveal significant differences in breast FNA practice among different types of institutions and between domestic and international laboratories, and provide a baseline for future breast FNA studies in a variety of practice settings.

Classification of Male Breast Lesions According to the IAC Yokohama System for Reporting Breast Cytopathology

OBJECTIVE

This study aims to determine the diagnostic utility of the International Academy of Cytology (IAC) Yokohama System for reporting breast cytopathology in lesions of the male breast.

STUDY DESIGN

Fine-needle aspiration biopsy (FNAB) reports between 2015 and 2019 were retrospectively recategorized according to the 5-tiered IAC Yokohama Reporting System. Our database yielded a total of 1,532 FNAB reports from breast lesions, obtained from 1,350 male patients. The risk of malignancy (ROM) and diagnostic performance of FNAB were determined using follow-up histopathological diagnosis and/or clinical follow-up, where available, for each category.

RESULTS

The category distribution were as follows: inadequate, 40%; benign, 57%; atypical, 0.6%; suspicious for malignancy, 0.7%; and malignant, 1.6%. The ROM in each category was nondiagnostic, 11%; benign, 3%; atypical, 28%; suspicious for malignancy, 56%; and malignant, 100%. The sensitivity, specificity, positive predictive value, and negative predictive value were recorded as 63, 100, 100, and 84.6% respectively, when only malignant cases were considered as positive tests.

CONCLUSION

This study validates the IAC Yokohama System for reporting male breast cytopathology. In accordance with the aim of the Yokohama System to establish best practice guidelines for reporting breast cytopathology, this comprehensive scheme facilitates comparisons between local and international institutions. The ROM acts as an internal audit for quality assurance within one's own laboratory and provides guidance for clinical management. It highlights inefficiencies such as high inadequacy rates for category 1 and also features strengths with impressive specificity for categories 4 and 5.

Distribution of breast lesions diagnosed by cytology examination in symptomatic patients at Eritrean National Health Laboratory, Asmara, Eritrea: a retrospective study

Background

Fine needle aspiration cytology is a simple, relatively accurate, non-invasive, and cost-effective method of diagnosing most breast pathologies. To date, there is no sufficient data depicting the distribution of breast lesions detected by fine needle aspiration cytology in our healthcare setting. The aim of this study was to elucidate the general distribution of breast lesions diagnosed by cytology test at Eritrean National Health Laboratory.

Methods

This retrospective study was carried out on 905 symptomatic patients between the years 2013 and 2017 at Eritrean National Health Laboratory. Diagnosis was made by fine needle aspiration cytology in patients with palpable breast lump and in some patients direct smear was prepared from a nipple discharge. Statistical analysis was carried out using Statistical Package for the Social Sciences version 23.

Results

A total of 905 patients were included in the study, of whom 871 (96.24%) were females. The age range of patients was from 13 to 93 years with mean and standard deviation of 33 ± 14.9 years. Breast lump, occurring in 892 (98.56%), was the most frequent presenting symptom. Fibroadenoma and fibrocystic breast lesions were the most prevalent lesions accounting for approximately 40% and 15%, respectively. Malignant breast lesions were seen predominantly in females above the age of 40 years with the highest frequency observed in the age range between 51 and 60 years. Pearson Chi-squared test showed significant association between patients’ age above 40 years and the risk of having a malignant breast lesion (p < 0.001). The highest number of benign and malignant breast lesions was documented in 2014 with little fluctuation elsewhere in the study period.

Conclusion

Fine needle aspiration cytology is a procedure of choice for preoperative diagnosis in breast lesions mainly in a resource-limited settings. Our study identified the occurrence of malignant breast lesions in young women, which is of a paramount public health concern. Of note, significant proportion of patients were late to seek medical attention. Therefore, enhancement of community awareness regarding breast disease and implementation of screening programs are necessary to ameliorate the morbidity and mortality associated with the disease.

Accuracy of the International Academy of Cytology Yokohama system of breast cytology reporting for fine needle aspiration biopsy of the breast in a dedicated breast care setting

BACKGROUND

The International Academy of Cytology (IAC) Yokohama system is a recently proposed system for reporting breast cytology by fine needle aspiration biopsies (FNAB). Multiple studies are needed to confirm the risk of malignancy (ROM) of the various reporting categories of this system. The present article studies the accuracy of the IAC Yokohama system in our center.

METHODS

Over a period of 1 year (September 2018-August 2019), all cases of breast masses assessed by FNAB and histological correlation were studied retrospectively. Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) and overall accuracy of the IAC Yokohama system for diagnosing malignancy were assessed. The rates of malignancy (ROM) of each diagnostic category were also estimated.

RESULTS

Three hundred and twenty-one FNABs had cyto-histological correlation. The percent sensitivity (with 95% Confidence Intervals) when the atypical, suspicious of malignancy and the malignant categories were regarded as positive for malignancy were 98.2% [95.5%, 99.5%], 96.0% [92.5%, 98.2%], and 86.7% [81.5%, 90.8%] respectively. The percent specificity (with 95% Confidence intervals) for the same categories in the same order were 59.5% [47.4%, 70.7%], 91.9% [83.2%, 97.0%], and 100% [95.1%, 100%] respectively. The area under curve (AUC) for diagnosing malignancy was 0.981[0.963, 0.993]. The ROM for the benign, atypical, suspicious of malignancy and malignant category were 8.3% [2.3%, 20.0%], 17.2% [5.8%, 35.8%], 77.8% [57.7%, 91.4%], and 100% [98.1%, 100%] respectively.

CONCLUSION

The IAC Yokohama system is suitable for accurately reporting breast lesions on FNAB.

Should uncertainty concerning the risk of malignancy be included in diagnostic (nongynecologic) cytopathology reports?

In diagnostic cytology, the known site-specific false positive rates at various anatomical sites for the risk malignancy (ROM) when a confirmed malignant diagnosis is made are comparatively well documented. ROM figures for diagnostic cytology specimens may vary according to the anatomical site of the specimen, the exact nature of the specimen received, the staining method(s) used, and the use of additional laboratory techniques including molecular profiling; furthermore, they often differ to some extent from institution to institution, between differing cytologists within the same institution, and over time. A brief literature review for a selected group of routine diagnostic cytology specimens shows a published ROM for a confirmed malignant diagnosis as follows: bile duct brushings, ~99% (range, 97%-100%); breast fine needle aspiration, 98.5% (range, 92%-100%); serous effusion fluid, 98.9% (range, 90%-100% although lower for squamous cell carcinoma, mesothelioma, and lymphoma), pulmonary endobronchial ultrasound cytology, ~99% (range, 86.6%-100%); thyroid FNA, 98% (range, 97%-99% if NIFTP tumors are excluded), salivary gland FNA, ~90%; (range 57%-100%) and lateral neck cyst FNA, ~99% (range, 95.5%-100%). Because most diagnostic cytology specimens have a small but accepted false-positive rate, this information is vitally important for the clinical management of patients and for shared patient decision making. In our view, the known false-positive rate for a given diagnostic cytology specimen could be included within the cytology report to assist in explaining the limitations of the diagnostic cytology interpretation and help facilitate the clinical decision-making process.

Interobserver Agreement for the International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy Cytopathology

BACKGROUND

A number of guidelines have been developed to improve standardization of the terminology and criteria for cytologic specimens obtained from the thyroid, pancreas, lung, and salivary glands. A major goal of these guidelines is to improve reproducibility and understanding of the reporting of diagnostic results among cytopathologists and between cytopathologists and clinicians. The International Academy of Cytology Yokohama System for Reporting Breast Fine-Needle Aspiration Biopsy Cytopathology (IAC YSRB) is the most recent of these guidelines. The value of this system is, in part, dependent upon interobserver reproducibility.

DESIGN

Ninety consecutive fine-needle aspiration biopsies (FNAB) of the breast, performed over a 6-year period, were independently evaluated by 4 board-certified pathologists blinded to the original diagnoses. The 5 diagnostic categories used were those of the IAC YSRB according to published criteria for these categories. Observed agreement and chance corrected agreement (Fliess κ) were calculated. Differences in κ values were evaluated using the T statistic of Gwent. Statistical calculations were performed using STATA v16.0 (STATA Corp., College Station, TX, USA).

RESULTS

Overall agreement between observers was good. Observed unweighted agreement was 69% and weighted agreement was 91%. The majority of diagnoses were concordant (68.6%).

CONCLUSIONS

Interobserver agreement of 4 cytopathologists was good using the 5 categories of the IAC YRSB (69%). Agreement was greater among pathologists with more years of experience. The IAC YSRB system appears to provide greater agreement among viewers than guidelines for cytologic specimens obtained from some other body sites (salivary gland and lung). Most discrepancies were only by a single category, with only 22/113 (19%) differing by more than one category.

Breast fine needle aspiration biopsy cytology: the potential impact of the International Academy of Cytology Yokohama System for Reporting Breast Fine Needle Aspiration Biopsy Cytopathology and the use of rapid on-site evaluation

The present report reviews the current problems associated with the routine use of breast fine needle aspiration biopsy (FNAB) and discusses the potential impact that the new International Academy of Cytology (IAC) Yokohama Reporting System and the use of rapid on-site evaluation (ROSE) should have on reducing these problems to optimize breast care for patients. The recently reported IAC System aims to establish the best practice guidelines for breast FNAB, emphasizing the importance of the FNAB technique and the skillful preparation of direct smears. The IAC System proposes a standardized report and established clear terminology for defined reporting categories, each of which has a risk of malignancy and is linked to management options. The FNAB techniques that will optimize the biopsy specimen and reduce poor quality smears are reviewed and the benefits of ROSE are discussed. FNAB can diagnose accurately the vast majority of breast lesions, and ROSE has been recommended whenever possible to reduce the rate of insufficient/inadequate cases and increase the number of specific benign and malignant diagnoses. ROSE performed by a cytopathologist provides a provisional diagnosis, reducing patient anxiety and facilitating management through cost-effective immediate triage and patient selection for ancillary testing. Thus, patients can be selected for immediate core needle biopsy, as required.