Comparative evaluation of the modified Scarff-Bloom-Richardson grading system on breast carcinoma aspirates and histopathology

BACKGROUND: Fine needle aspiration (FNA) is a quick, minimally invasive procedure for evaluation of breast tumors. The Scarff-Bloom-Richardson (SBR) grade on histological sections is a well-established tool to guide selection of adjuvant systemic therapy. Grade evaluation is possible on cytology smears to avoid and minimize the morbidity associated with overtreatment of lower grade tumors. AIM: The aim was to test the hypothesis whether breast FNA from the peripheral portion of the lesion is representative of Scarff-Bloom-Richardson grade on histopathology as compared to FNA from the central portion. MATERIALS AND METHODS: Fine-needle aspirates and subsequent tissue specimens from 45 women with ductal carcinoma (not otherwise specified) were studied. FNAs were performed under ultrasound guidance from the central as well as the peripheral third of the lesion for each case avoiding areas of necrosis/calcification. The SBR grading was compared on alcohol fixed aspirates and tissue sections for each case. RESULTS: Comparative analysis of SBR grade on aspirates from the peripheral portion and histopathology by the Pearson chi-square test (χ(2) =78.00) showed that it was statistically significant (P<0.001) with 93% concordance. Lower mitotic score on aspirates from the peripheral portion was observed in only 4 out of 45 (9%) cases. The results of the Pearson chi-square test (χ(2) = 75.824) with statistically significant (P=0.000). CONCLUSION: This prospective study shows that FNA smears from the peripheral portion of the lesion are representative of the grading performed on the corresponding histopathological sections. It is possible to score and grade by SBR system on FNA smears.