Breast lesions are a heterogeneous group of disorders ranging from inflammatory lesions to invasive cancers. Breast cancer is the most common malignant neoplasm among women worldwide after non-melanoma skin malignancies. Further, it is the most frequent cause of cancer-related death among women worldwide, with an estimated 2.1 million new cases annually. The survival rate varies by continent, with better rates in developed countries[1]. The implementation of breast cancer screening programs is helpful for the early detection of breast lesions that, in turn, translate to a significant decrease in mortality. Lesions suspected of malignancy should be subjected to complementary tests as soon as possible for diagnostic confirmation[2].

The most common modality for the initial evaluation of breast lesions is fine-needle aspiration cytology (FNAC). In addition, some studies recommend that small breast lesions or those suspicious for malignancy should be evaluated through histopathological examination ("core needle biopsy" or excision). However, FNAC is a more simple, low-cost technique with a low risk of complications than that observed with biopsy or excision procedures [4]. FNAC, when performed inadequate conditions, has good accuracy. The aspirated specimen can also be processed as a cell block that can be used for immunohistochemical analysis of related biomarkers (e.g., estrogen receptor, progesterone receptor, and Her2)[5]. The cellblock specimen can also be used for molecular analysis, providing additional information that can be helpful in the diagnosis and treatment by identifying predictive and prognostic markers. Early diagnosis and small lesion size significantly improve the treatment outcomes and prognosis of patients with breast lesions, especially those with malignant lesions

Breast masses are the most common complaint with which females patients present to the hospital. The majority of these lesions are either benign or non-neoplastic [6]. Fine needle aspiration cytology (FNAC) is one of the most common tests for palpable lesions. FNAC is also a part of the triple assessment test for breast masses [7]. It is minimally invasive, cost-effective and diagnostic accuracy is good [8]. Rapid turnaround times help in the same-day diagnosis of breast lesions and early management. Malignant diseases are more common after menopause [4].

(1%), Malignant Phyllodes tumour (1%) and Lobular Carcinoma(1%) as shown in Table 1.

Table 1: Spectrum of Malignant Breast Lesions on FNAC

Table 2: Comparison of Malignant Breast lesions among various studies.

Figure 1: Smears studied shows malignant ductal epithelial cells seen in dyscohesive clusters. These tumour cells have a high N/C ratio with a moderate to scanty amount of cytoplasm. These features are suggestive of Ductal Carcinoma Breast( 1A: Leishman stain, 10 X and 1B: Leishman stain, 40 X)

Figure 2: Smear studied shows clusters of tumour cells with mild to moderate nuclear

Mucinous carcinoma has an excellent 5-year survival rate and a low rate of distant and local recurrence.[13]. Tubular carcinoma is composed of well-formed tubules, often shaped like teardrops [12]. This type of carcinoma is uncommon, at only 2% of invasive breast carcinomas, and is associated with an excellent prognosis. Tubular carcinoma is generally ER-positive/HER2-negative[13].

Metaplastic carcinoma is a heterogeneous category of neoplasms that have differentiated into squamous or mesenchymal cells. Greater than 90% of metaplastic carcinomas are ER-negative/HER2-negative. Compared with other TNBCs, metaplastic carcinoma has a worse clinical outcome and lower chemotherapy response rate [13]. Medullary carcinoma comprises solid syncytial sheets of pleomorphic cells with prominent nucleoli, a lymphoplasmacytic infiltrate numerous mitoses, and a pushing border[12]. These tumours are typically triple-negative and often associated with BRCA mutations. Traditionally, these tumors were reported to have a relatively favorable prognosis; however, due to the low level of reproducibility for the diagnosis and the poor prognosis associated with TNBCs, these tumors are now termed "carcinomas with medullary features" and treated with aggressive therapy [13].

Molecular gene expression profiling studies heralded a new era in the classification of breast carcinomas. In addition to morphology, breast carcinomas now are categorized into 1 of 3 subtypes based on the tumour's expression of HER2 and E.R.s. Although testing is almost always performed for P.R. as well as E.R., descriptions of molecular classifications generally use E.R. status as a surrogate marker for P.R. as well. The three subtypes are ER-positive/HER2-negative (50%-65% of tumours). HER2-positive (10%-20% of tumors). ER-negative/HER2-negative (10%-20% of tumors) [14].

ER-positive/HER2-negative breast cancers: These are often associated with losses of chromosome 16q and gains in chromosome 1q, as well as activating mutations in PIK3CA, a growth factor receptor signalling molecule. This type of breast carcinoma often progresses through a sequence that can include flat epithelial atypia, atypical ductal hyperplasia, ductal carcinoma in situ (DCIS), and eventually invasive ductal carcinoma. This subtype is primarily treated with hormone therapy instead of chemotherapy because few of these carcinomas respond to chemotherapeutic drugs.

Moreover, FNAC has good sensitivity, specificity and accuracy in the diagnosis of both malignant and non-malignant breast lumps. Accuracy can be improved by multiple sampling from different angles and by using ultrasound guidance in very small lumps [20]. Malignant breast lesions were found in all age groups. This finding follows a study by Rahman et al.[21], who also concluded that most malignant lesions were found in the middle age group of 31 to 50 years. Similar results from other studies in India like Muddegowda et al.[22].and Khemka et al [23]were reported. However, reports from the western world depict the 5th and 6th decades as the predominant age group for breast cancer [24]. Present study findings of 14.6% cases are similar to a study done by Modi et al. [25], which found 16.7% cases. The other comparison studies are shown in Table 2. The management of breast disease needs a deliberate, synchronized diagnostic and treatment strategy. Fine-needle aspiration cytology (FNAC) is an essential diagnostic tool for the preoperative diagnosis of palpable and non-palpable breast lesions. Our study has the limitation of having a small sample size, and being a retrospective study, there will be deficiencies incomplete data collection. However, it provides baseline data of the patient population presenting to our hospital.

For diagnosing the nature of palpable breast lesions, FNAC is considered a highly accurate procedure with sensitivity and specificity as high as 95%. Its use has been recommended in literature as a preliminary treatment on an outpatient basis. Early diagnosis is of paramount importance to decrease the mortality and morbidity associated with these lesions. FNAC is a relatively simple procedure with good patient acceptance and low morbidity. It is an accurate, safe and repeatable procedure in the diagnosis of various breast lesions –both malignant and non-malignant. Repeated passes should be made for a greater yield of cytological material. FNAC should be used earlier and more frequently to shorten the diagnostic interval and allow more prompt therapy for malignant breast lesions.

FNAC helps in rapid diagnosis and early management of malignant breast lesions.