Is FNA Still a Useful Tool in the Diagnosis of Breast Masses? A 5-Year Review with Cytohistopathologic Correlation

Abstract

Introduction. Breast cancer is the most common cancer among women worldwide. In the Philippine National Cancer registry, 1 in every 13 Filipino women is likely to suffer from breast cancer. Fine needle aspiration cytology (FNAC) is a safe, accurate, fast and economical technique practiced worldwide in breast cancer diagnosis. Objective. To assess the value of FNAC as a rapid diagnostic tool in the local setting with the expectation to provide an immediate and highly reliable diagnosis in more than 90% of breast lesions. Methodology. From January 2010 to December 2014, there were 306 out of 1465 breast FNAC documented cases with histopathological correlation. The FNAC smears were retrieved, retrospectively reviewed blindly and reclassified into 5 categories (C1- C5). All FNAC were performed by pathology residents, pathologists and cytopathologist. Smears were fixed in 95% ethyl alcohol and stained with Papanicolaou method. Results. The FNAC findings showed: 13 (4.25%) unsatisfactory (C1); 160 (52.29%) benign (C2); 23 (7.52%) atypical (C3); 9 (2.94%) suspicious (C4) and 101 (33.01%) malignant cases (C5). There were 120 (39.22%) malignant and 186 (60.78%) benign lesions. There were 3.92% (12/306) false negative and 0.65% (2/306) false positive cases. The FNAC had 90% sensitivity, 99% specificity, 98% positive predictive value, 99% negative predictive value and 95% accuracy. The risks of malignancy for each category were: C1=15%; C2=4%; C3=13%; C4=78% and C5=100%. Conclusion. Despite the increasing preference for core needle biopsy among surgeons, FNAC continues to be an acceptable, affordable, quick and valuable tool contributing significantly to early breast cancer diagnosis and treatment, particularly in developing countries like the Philippines. Owing to its high sensitivity and specificity, it can be used as a screening and confirmatory diagnostic tool. Malignant and benign interpretations of breast FNAC give highly accurate prediction of outcomes but must be correlated with clinical and mammographic findings.