Categorization of Breast Fine Needle Aspirates Using Yokohama Classification and Its Correlation With Histopathological Findings

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.

Background: Breast lumps pose a significant health concern globally, contributing to both illness and death. The International Academy of Cytology (IAC) Yokohama system has established a uniform method for reporting breast cytology, categorizing it into five groups: inadequate, benign, atypical, suspicious, and malignant. Aims and Objectives: This study primarily aimed to evaluate breast lesions using the IAC Yokohama System and compare the results with those of corresponding histopathological biopsies. Additionally, the study aimed to analyze the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of breast fine-needle aspiration cytology (FNAC) and determine the risk of malignancy associated with each category. Materials and Methods: In this study, 92 cases were analyzed and categorized according to the IAC Yokohama System. Sensitivity, specificity, PPV, NPV, diagnostic accuracy, and risk of malignancy were determined based on histopathological diagnosis, which was considered the reference standard. Results: Among the 92 breast FNACs, the risk of malignancy for the categories insufficient, benign, atypical, suspicious, and malignant were 0%, 0%, 18.75%, 100%, and 100%, respectively. The highest sensitivity (100%) was achieved when considering atypical, suspicious, and malignant cases as positive results. The specificity was highest (100%) when only malignant or both malignant and suspicious cases were considered positive results. The highest diagnostic accuracy (95.65%) was observed when including malignant and suspicious cases as positive results. Conclusion: Implementing the IAC Yokohama System for reporting breast cytopathology through structured reporting will enhance the quality, clarity, and reproducibility of reports among pathologists and clinicians, which would result in enhanced patient care and management.

Introduction: Fine Needle Aspiration Cytology (FNAC) is a rapid, minimally invasive and cost-effective procedure with a high sensitivity rate of 92-95% and high Positive Predictive Value (PPV) approaching 100% for the diagnosis of breast malignancies. International Academy of Cytology (IAC) Yokohama system for reporting breast FNACs had been established in 2016 to bring consistency and uniformity of breast cytology reporting. Aim: To classify the breast lesions according to the IAC Yokohama system for cytological reporting of breast lesions. Materials and Methods: This was a retrospective six years study carried out in the Department of Pathology, Karpaga Vinayaga Institute of Medical Sciences, Chinnakolambakkam, Tamil Nadu, India. All females breast FNAC cases reported during the year January 2015 to December 2020 were included in the study according to the inclusion criteria. Relevant clinical and pathological data including the FNAC reports were retrieved from the medical records of the department. Corresponding FNAC smears stained with Haematoxylin and Eosin (H&E) and Papanicolaou stains were reviewed and double-checked with the FNAC reports. All those cases were grouped according to the IAC Yokohama System. Statistical analysis was carried out using Statistical Package for the Social Sciences (SPSS) version 23.0. Results: Of the total 381 female breast FNACs, majority (60%) of them belonged to the age group of 21-40 years. The predominant presenting symptom was palpable breast lump (73%) and Upper Outer Quadrant (UOQ) was involved in 65% of cases. Out of 381 cases, 297 (78%) were benign, 52 (13.6%) were malignant and 32 (8.4%) were inadequate for diagnosis. Total 73.8% cases belonged to “C2” category and fibroadenoma was the most prevalent lesion. Pearson Chi-square test showed highly significant association between patient’s age above 40 years and the risk of having a malignant breast lesion (p<0.0001). Conclusion: FNAC is an effective diagnostic modality for preoperative diagnosis of breast lesions thereby facilitating proper treatment at an early stage of the disease. Also adherence to the standardised cytological reporting system like IAC Yokohama system will ensure quality assurance across various institutions, thereby strengthening the healthcare services.

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.

BackgroundFine-needle aspiration cytology (FNAC) of the breast is a well-established technique that aids in the preoperative identification and differentiation between nonneoplastic and neoplastic breast lesions. Breast lesions can be efficiently categorized into different cytological groups using the International Academy of Cytology (IAC) Yokohama System. The aim of this study was to classify breast lesions based on the proposed Yokohama system of reporting breast cytology and identify the need for a unified system of reporting breast lesions.Materials and methodsThis retrospective descriptive study was performed in the Department of Pathology, Government Medical College, Datia, M.P. from January 2019 to June 2023. A total of 762 FNAC slides reported during this period were retrieved, re-examined and reclassified according to the IAC Yokohama System. Histopathological diagnoses were also retrieved and correlated with the cytological findings wherever available.ResultsIn the present study, a total of 762 smears of breast fine needle aspirations were included and categorized using the IAC Yokohama System. There were 3.8% cases (29/762) in the C1 category (insufficient), 71.6% cases (545/762) in the C2 category (benign), 6.3% cases (48/762) in the C3 category (atypical), 3.1% cases (24/762) in the C4 category (suspicious for malignancy) and 15.2% (116/762) cases in the C5 category (malignant).ConclusionFNAC is a reliable diagnostic technique for the evaluation and management of breast lesions prior to surgery. Implementing the IAC Yokohama System for reporting breast cytopathology enhances the accuracy of diagnosing breast lesions, reduces missed diagnoses, and offers reliable estimates of risk of malignancy. Adopting the Yokohama system is a crucial first step in boosting the overall effectiveness of breast cytology reporting among clinicians and pathologists, which will ultimately lead to improved communication and patient care.

Objective: To evaluate the potential diagnostic role of the myoepithelial marker p63 in fine needle aspiration cytology (FNAC) of breast in comparison to other diagnostic tools. Study Design: A total of 49 FNAC of breast were assessed according to clinical, mammographic, cytological findings, and p63 immunostaining on FNAC. The strength of agreement with final histological diagnosis (FHD) was measured by kappa test. Results: p63 was positive in myoepithelial cells of 75% (9/12) of benign cases and negative in 89% (33/37) of the malignant cases with strong agreement with the FHD (p < 0.0001, ĸ = 0.63). All the malignant positive cases showed variable degrees of in situ component. Only one malignant case (1/37, 0.03%) showed few p63 positive neoplastic cells in FNAC. Combined FNAC and p63 staining (with <25% cutoff point) to diagnose malignancy showed 100% sensitivity, 75% specificity, 92% positive predictive value, 100% negative predictive value, and 94% diagnostic accuracy. Most of the cytologically suspicious cases (7/9, 78%) showed negative p63 staining results, and all these suspicious cases (100%) proved to be malignant by the FHD. There was poor agreement between diagnosis according to positive background naked nuclei (NN) and the FHD (ĸ = 0.24 and p < 0.0001); however, presence of more than 74% positive NN is strongly suggestive of fibroadenoma. Conclusion: p63 immunostaining with a cutoff value of <25% to diagnose malignancy is a highly sensitive and specific myoepithelial marker which is recommended as an adjuvant tool to FNAC of breast in suspicious cases.

Standardized reporting of breast FNAC using the International Academy of Cytology Yokohama system and its comparison with histopathology: a cross-sectional study

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: 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: The International Academy of Cytology (IAC). Yokohama System has created a standardized method of describing breast cytology by grouping them into five categories: inadequate, benign, atypical, suspicious, and malignant. To validate the likelihood of cancer in the various categories, several investigations have been undertaken at various institutions as a mandate. Aim: The main objective of the research is to identify the accuracy of fine-needle aspiration cytology (FNAC) for breast lumps by the Yokohama system for reporting and its correlation with histopathology. Methodology: The present study was a retrospective research performed over 8 months. Fine-needle aspiration cytology (FANCs) for breast lumps are performed by the Yokohama system. Whenever accessible, histopathological diagnoses were also retrieved. Statistical Analysis Used: Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were estimated using a histological diagnosis as the gold standard concerning each of the five categories. Results: Out of 200 cases, 106 had histopathological concordance. Five categories: insufficient, benign, atypical, suspicious, and malignant of the IAC Yokohama system were 1.00%, 62.50%, 4.50%, 1.50%, and 30.50%, Category 1 (1%), Category 2 (62.5%), Category 3 (4.5%), Category 4 (1.5%), and Category 5 (30.5%). When malignant, suspicious, and unusual cases were taken into account as positive test findings, the highest level of sensitivity (90.60%) was attained. The maximum specificity (100%) was seen when only malignant patients were taken into account as positive test findings, but the highest diagnostic accuracy (96.22%) was shown when the malignant and suspect categories were taken into account as positive test results. Conclusion: FNAC using the Yokohama system for reporting is an accurate diagnostic tool for breast lumps. The system provides a standardized framework for reporting FNAC findings, and studies have reported high sensitivity and specificity rates for diagnosing breast lumps using FNAC. Therefore, FNAC can be used in conjunction with histomorphology to ensure accurate diagnosis and appropriate management of breast lumps.

Background: Fine-needle aspiration cytology (FNAC) has been used extensively in the diagnosis of breast lesions, but false-negative rates are a matter of concern. Immediate onsite evaluation of breast lesions, combining FNAC results with clinical and radiological data allows improving its diagnostic accuracy. The objective of this study was to evaluate the diagnostic accuracy of a large series of FNAC of breast lesions during the first 3-year period of a dedicated one-stop clinic, by comparing the FNAC results with the corresponding definitive histological examination outcome or the results of the radiological follow-up at 18 months. Method: Data of all consecutive patients (pts) whose lesions were prospectively characterized by ultrasonography (US) and diagnosed by FNAC in the one stop clinic of the Institute Gustave Roussy between May 2004 and March 2007. Histological verification by core-needle biopsy or surgery was systematically performed for lesions classified malignant or suspicious by cytopathology, and for benign lesions, when no perfect concordance between clinico-radiologic features and FNAC results (such as benign FNAC but BI-RAD 5) was found. For non-operated patients, follow-up consisted on biannual US and/or mammography; the results at 18 months were considered. Pts characteristics, radiological findings, cytopathological and histological results were extracted from the hospital computerized prospectively registered medical records. Complete sensitivity (number of carcinomas that were malignant or suspicious by cytopathology) and full specificity (benign lesions at cytology of the total number of benign lesions) were calculated by comparing the cytopathological results to the histological or the long-term follow-up status. Results: A total of 1822 nodular breast lesions (mean size: 20 mm, BI-RAD ACR 1/2/3/4/5/unknown: 10/96/471/459/777/9) in 1739 pts (mean age: 56 years) were studied. FNAC was US-guided in 1115 lesions (61 %). Lesions were classified by FNAC as malignant in 842 (46%), benign in 771 (42%), suspicious in 154 (9%), and unsatisfactory in 55 (3%) cases. Complete sensitivity (number of carcinomas that were malignant or suspicious by cytopathology) was estimated at 98.5%, whereas full specificity (benign lesions at cytology of the total number of benign lesions) was equal to 94.4%. There were 4 false-positive lesions and 32 false-negative lesions, but all these lesions except one were operated as radiological results were suspicious of malignity. Conclusions: Breast FNAC performed in a dedicated one-stop clinic with immediate on-site diagnosis presented a low rate of unsatisfactory specimens and a very efficient tool for triaging patients candidates for histological evaluation conversely for follow-up by imaging. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-01-05.

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.

635 Background: Fine-needle aspiration cytology (FNAC) has been used extensively in the diagnosis of breast lesions, but false-negative rates are a matter of concern. However, immediate onsite evaluation of breast lesions, combining FNAC results with clinical and radiological data allows to improve its diagnostic accuracy. The objective of this study was to evaluate the concordance between cytopathological and histological results in a large series of FNAC performed during the first 3-yr period of the dedicated one-stop clinic set up in our institution since 2004. Methods: We reviewed data of all patients (pts) seen in the one stop clinic between May 2004 and March 2007 who had a lesion diagnosed by FNAC and verified by histology. For benign lesions, histological verification of the lesion was mandatory each time there was no perfect concordance between clinico-radiologic features and FNAC results (such as benign FNAC but BI-RAD 5). Pts characteristics, radiological findings, cytopathological and histological (by per-cutaneous biopsy or surgery) results were extracted from the hospital computerized prospectively registered medical records. Results: A total of 1053 nodular breast lesions (mean size: 24±23 mm, BI-RAD ACR 1/2/3/4/5: 2/10/68/283/684) in 1015 pts (mean age: 59±13 years) were studied. FNAC was US-guided in 521 lesions (49.4%). FNAC classified lesions as malignant in 741 (70.4%), benign in 127 (12.0%), suspicious in 143 (13.6%), and unsatisfactory in 42 (4.0%) cases. Among definitive benign or malignant diagnosis, FNAC and histological results showed concordance in 840/868 (96.7%) cases (738 malignant and 102 benign cases). The numbers of false-negative and false-positive lesions were respectively 25/127 (19%) and 3/741 (0.4%). Among the 143 suspicious and 42 unsatisfactory specimens, 114 and 20 were malignant, respectively. Conclusions: FNAC performed in a one-stop clinic allows obtaining an immediate on-site diagnosis of breast cancer with a good concordance with histological results and low rate of unsatisfactory specimens. However, affirming benign lesion requires a multi-disciplinary team: whenever clinico-radiologic features and FNAC results are non concordant, histologic assessment is mandatory. No significant financial relationships to disclose.