Imprint Cytology of Axillary Lymph Nodes in Breast Carcinoma Following Neoadjuvant Chemotherapy

Objective To evaluate the efficacy of imprint cytology (IC) in detecting residual axillary metastasis following neoadjuvant chemotherapy (NACT) in order to check its feasibility on sentinel nodes in the posttherapy setting in patients with breast carcinoma. Study Design Thirty women on NACT for locally advanced breast cancer were subjected to total mastectomy with axillary node dissection. Routinely stained imprints from 172 resected nodes were studied to detect residual metastasis and therapy-induced changes, adopting a semiquantitative grading system for assessing the cell yield. Sensitivity and specificity tests were performed. The effect of cellularity in detecting malignancy was statistically determined by the McNemar test. Results Of the 172 nodes, 58 (33.7%) and 64 (37.2%) were positive by IC and histopathologic examination, respectively. Sparse, moderate and high cell yield was observed in 27 (15.2%), 33 (19.4%) and 112 (66.4%) nodes, respectively. No statistically significant difference was found with respect to the cellularity of imprints. Sensitivity, specificity and diagnostic accuracy were 89.1 %, 99.1% and 95.4%, respectively. The false positive and negative rates were 0.6% and 4.1%, respectively. The positive and negative predictive values were 98.3% and 93.9 %, respectively. Conclusion IC is a sensitive, specific and accurate method of detecting axillary metastasis in patients with down-staged tumors following chemotherapy. The fact that therapy did not affect the cell yield on IC makes the technique very applicable for assessing the sentinel nodes following NACT.