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

Abstract

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.

Diagnostic Accuracy of the International Academy of Cytology Yokohama System versus the Modified Masood’s Scoring Index in Categorization and Diagnosis of Palpable Breast Lesions

“…This can be a major cause of diagnostic pitfall, as the paucity of tumour cells and abundance of mucin can lead to aspiration of insufficient material [15]. In the atypical category, ROM was 20%, which is comparable to similar studies done by various authors [12][13][14]16]. Follow-up on histopathology for the cases included fibroadenomas, usual ductal hyperplasia, proliferative fibrocystic changes, phyllodes tumour, or papilloma.…”

Insufficient/inadequate category in breast cytology: Are the standardized guidelines of rapid on‐site evaluation available to reduce its rate?

“…They do not follow malignancy in the insufficient class reported with ROSE. Ahuja et al 6 report 5% ROM in the insufficient category said with ROSE.…”

“…These studies report ROM in the different categories of IACYS. The ROM was ranged in categories II 0.4% to 8.3%, III 1.3% to 50%, IV 55.55% to 100%, and V 97% to 100% 4–18 . The ROM in category I without ROSE ranges from 0% to 60.87% 4–18 and 0% to 11.11% 8,17 with ROSE.…”

“…The ROM was ranged in categories II 0.4% to 8.3%, III 1.3% to 50%, IV 55.55% to 100%, and V 97% to 100% 4–18 . The ROM in category I without ROSE ranges from 0% to 60.87% 4–18 and 0% to 11.11% 8,17 with ROSE. Wong et al (2019) and Wong et al (2021) observed a statistically significant difference in category 1 and category 5 when FNAB with ROSE compared with FNAB without ROSE 17 .…”

“…The ROM was ranged in categories II 0.4% to 8.3%, III 1.3% to 50%, IV 55.55% to 100%, and V 97% to 100%. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] The ROM in category I without ROSE ranges from 0% to 60.87% [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] and 0% to 11.11% 17 The IACYS has also endorsed the use of ROSE whenever possible to reduce the rate of insufficient/inadequate FNAB. 19 The many advantages of ROSE in overall cytology are described in the literature.…”