Residual nodal disease in biopsy proven n1/n2 breast cancer following neoadjuvant systemic therapy

The purpose of this study was to determine the rate of complete pathologic response in axillary lymph nodes after neoadjuvant therapy and the clinicopathologic factors associated with a complete response.

Clinical, demographic, and pathologic data from all patients with breast cancer treated at our institution are prospectively recorded in a database. We reviewed this database from 2000 to 2007 and identified 90 patients who were node-positive before neoadjuvant therapy based on image-guided fine needle aspiration biopsy; all 90 patients underwent axillary lymph node dissection (ALND) after neoadjuvant therapy. Data were compared using chi-square and Fisher's exact test.

Of 90 patients with breast cancer who were node-positive before neoadjuvant therapy, 71 (79%) had positive nodal disease on final ALND pathology and 19 (21%) had a complete nodal pathologic response. Age, race, tumor grade, clinical T and N stage, and estrogen/progesterone receptor and Her-2neu status were not predictive of a complete nodal response. The only factor predictive of a complete nodal response was the type of neoadjuvant therapy used; all 19 patients with a complete response received neoadjuvant chemotherapy and none received neoadjuvant endocrine therapy (P < 0.05).

Twenty-five percent of patients who underwent neoadjuvant chemotherapy had a complete pathologic response in the nodal basin, whereas no patient who underwent neoadjuvant endocrine therapy experienced a complete nodal response. Twenty-five percent of patients who underwent neoadjuvant chemotherapy had a complete pathological response in the nodal specimen, whereas no patient who underwent neoadjuvant endocrine therapy experienced a complete nodal response.