Discussion

Breast lumps constitute a common clinical presentation and may represent a wide spectrum of benign and malignant lesions. Accurate preoperative diagnosis is essential for appropriate management and to avoid unnecessary surgical interventions. The concept of triple assessment, which includes clinical examination, radiological evaluation, and pathological diagnosis, plays a pivotal role in the early detection and treatment of breast lesions. Among the pathological modalities, FNAC remains a simple, minimally invasive, cost-effective, and rapid diagnostic technique. However, the lack of uniform reporting in the past often led to variability in interpretation and communication between cytopathologists and clinicians. The introduction of the IAC Yokohama System has addressed these issues by providing standardized diagnostic categories with an associated ROM and management recommendations.

In the present study, the majority of patients belonged to the younger and middle age groups, with the highest frequency observed in the 15-24 years and 25-44 years age groups. This finding is consistent with the known epidemiological pattern in developing countries, where benign breast lesions such as fibroadenoma are more prevalent among younger women. Similar observations were reported by Chauhan V et al. [23], where the most commonly affected age group was 21-40 years. The relatively lower number of cases in older age groups in our study may reflect increased awareness and early consultation among younger patients.

The present study demonstrated a predominance of benign lesions, with Category II constituting the majority of cases. Fibroadenoma was the most common benign lesion, followed by fibrocystic changes and inflammatory conditions. This distribution is comparable to several previous studies, which have also reported a higher frequency of benign breast lesions on FNAC. The relatively low proportion of malignant cases in our study could be attributed to early presentation and increased screening practices.

The ROM in our study showed a progressive increase across the Yokohama categories, which validates the clinical utility of this classification system. Category I showed no ROM, while Category II demonstrated a low ROM of 1.92%, highlighting the reliability of benign cytological interpretation. Category III exhibited an intermediate ROM of 33.3%, reflecting the heterogeneous nature of atypical lesions and emphasizing the need for close clinical and radiological follow-up. Categories IV and V showed 100% ROM, indicating a strong correlation between cytological suspicion and histopathological confirmation of malignancy. These findings are in agreement with the study by Agarwal A et al., which also reported 0% ROM in Category I and 100% ROM in Category V [11]. However, the study by De Rosa F et al. reported a higher ROM in Category I, which could be due to sampling variability or differences in study design and population [10].

The sensitivity, specificity, PPV, and NPV of FNAC in the present study were 87.5%, 96.4%, 77.7%, and 98%, respectively. These results are comparable with those reported by Yalavarthi S et al. [24] and Mehra K et al. [25], although slight variations may be attributed to sample size, patient selection, and institutional experience. The high specificity and negative predictive value observed in our study indicate that FNAC is particularly effective in ruling out malignancy, thereby reducing unnecessary surgical biopsies. The comparatively lower positive predictive value may be related to the small number of malignant cases and occasional false-negative interpretations.

The discordant case observed in the present study, where a lesion diagnosed as fibroadenoma on cytology was confirmed as invasive carcinoma on histopathology, highlights the limitations of FNAC. Possible reasons include sampling error, tumor heterogeneity, or well-differentiated carcinoma mimicking benign lesions. Such cases underscore the importance of clinicoradiological correlation and repeat biopsy in suspicious or discordant cases.

The Yokohama System also improves communication between clinicians and pathologists by providing a clear framework for reporting and management. Category-wise ROM helps guide treatment decisions, such as observation for benign lesions, further evaluation for atypical lesions, and definitive management for suspicious or malignant lesions. The system also promotes quality assurance, training, and research by enabling uniform data comparison across institutions. Overall, the findings of the present study support the reliability and clinical relevance of the IAC Yokohama System in categorizing breast FNAC. The system provides standardized reporting, improves diagnostic accuracy, and assists in predicting the ROM, thereby facilitating appropriate patient management.

Furthermore, Birundha B et al. [26] observed that lower-grade tumours were more frequently hormone receptor positive, indicating a better prognosis and response to hormonal therapy. Early detection of such lesions through FNAC and standardized reporting systems like the Yokohama classification can facilitate timely histopathological confirmation and receptor testing. This multidisciplinary approach contributes to personalized management and improved survival outcomes in breast cancer patients. Therefore, integrating cytological findings with histological grading and receptor status enhances the overall diagnostic and therapeutic strategy in breast tumour management.

Limitations

The study included only 63 cases, which may limit the generalizability of the findings. Being conducted in a single tertiary care institution, the results may not reflect the broader population. Only cases with available histopathology were included, which may have led to selection bias. Although triple assessment is recommended, detailed radiological correlation was not statistically evaluated.