M.J. Diaz-Ruiz 1 ; A. Soldevila 1, A. Arnau 2 ; R. Monmany 1 ; O. Valencoso 1 ; D. Coll 1 ; A. Miguel 3, T. Montes 4, V. Villa 5. 1 Radiology Service. 2 Innovation and Research Unit. 3 Oncology Service. 4 Gynecology Service. 5 Pathology Service. Fundació Althaia, Xarxa Assistencial de Manresa. Barcelona. PURPOSE To assess the diagnostic accuracy of fine needle aspiration (FNA) to detect axillary metastases for presurgical staging of breast cancer (BC) and assess its impact on therapeutic decision. DIAGNOSTIC ACCURACY OF FINE-NEEDLE ASPIRATION TO DETECT AXILLARY METASTASIS IN BREAST CANCER PATIENTS CONCLUSIONS  Axillary FNA is a useful technique in the presurgical staging of patients with BC. It allows reducing the number of SSLNB (18%) and, when positive, offers a fast, cost-effective tool for the diagnosis of axillary lymph nodes. METHODS AND MATERIALS Ultrasonography (US) was performed in 341 axillas of 332 patients diagnosed of breast cancer between July 2005 and June 2009 who subsequently underwent surgery. FNA was performed when suspicious lymph nodes were detected. Axillary lymphadenectomy was performed when FNA samples were positive for BC metastasis. Patients with negative ultrasonography or FNA and breast tumours ≤30mm were candidates for selective sentinel lymph node biopsy (SSLNB). Anatomopathological results of lymphadenectomy or SSLNB were used as reference tests. RESULTS REFERENCES - Banerjee M. J.Clin.Oncol Jul 1;22(13): Cianfrocca M. Oncologist 2004;9(6): Altomare V. Surg.Today 2007;37(9): Bedi DG. AJR Am.J.Roentgenol Sep;191(3): Van der Valk P. Histology for pathologists. In: Lippincott Raven, editor. 2nd ed. Philadelphia: Stenberg SS, ed; p Abe H. Radiology 2009 Jan;250(1): Kuenen-Boumeester V. Eur.J.Cancer 2002;38:82. 1.We calculated the Diagnostic accuracy of FNA excluding 9 patients that appeared at first to be false-positive for metastasis, but who had received preoperative neoadjuvant chemotherapy. N = 154. CI 95% = Confidence Interval 95%, TP = true-positive, TN = true-negative. FP = false- positive, FN = false-negative, PPV = positive predictive value, NPV = negative predictive value, and DA = diagnostic accuracy  Of the 151 patients with involved nodes at surgery, preoperative US identified nodes in 96 patients (63,6%), of which 93 (96,7%) met the criteria for puncture and 79 (77,5%) of these were diagnosed preoperatively by FNA.  Of the 75 patients with negative FNA the axillary surgery results confirmed the negativity in 47 patients.  In 36 (51,4%) of the 79 pacients with positive FNA, there was histologic evidence of metastasis in ≤3 of the dissected axillary lymph nodes (pN1). 2. Surgical results in patients with positive FNA. N = 79. FNA results Surgical results Total PositiveNegative Positive790 Negative Total N%IC 95% TP79/154-- TN52/154-- FP0-- FN23/154-- Sensitivity79/10277,568,1-85,1 Especificity52/ ,2-100 PPV79/ ,4-100 PNV52/7569,357,6-79,5 DA131/15485,178,4-90,3 pNNo. axillae% % (excluding preoperative neoadjuvant chemotherapy) pN0911,4- pN13645,651,4 pN21822,825,7 pN31620,322,9 Total79100 Image shows US-guided FNA technique, with tip of needle in suspicious lymph node. BC + axillary US 341 axillas Lymphadenectomy 60 axillas SSLNB criteria 281 axillas No FNA 170 axilas FNA 111 axillas Negative FNA 60 axilas Positive FNA 51 axilas (18%) 3. Impact of the FNA on therapeutic decision