Preoperative Assessment of the Axilla by Ultrasonogram-Guided FNAC in Breast Cancer Patients with a Clinically Negative Axilla

Ultrasonogram-guided fine needle aspiration cytology of the axillary lymph nodes using a 7–12 MHz linear transducer was carried out on 102 breast cancer patients in whom there was no clinically palpable lymph node in the axilla. Ultrasound was able to visualize an axillary node in 55 patients (54%) while in 47 patients (46%), no node was visualized. USG-guided FNAC on the 55 patients found 9 (16%) patients to be positive for metastases, 27 (49%) to be negative, and 19 (35%) in whom an inconclusive or inadequate sample was reported. On correlation with post-modified radical mastectomy (MRM) histopathology, the preoperative USG-guided FNAC had a sensitivity of 60%, specificity of 100%, and an overall diagnostic accuracy of 58%. It can be concluded that patients with a positive for malignancy USG-guided FNAC report on the axilla should be treated as such. Patients who have a negative for malignancy or inconclusive/inadequate FNAC report or in patients in whom no axillary node is visualized on USG should undergo a sentinel node biopsy procedure for further evaluation of the axilla.