Sentinel node biopsy after neoadjuvant chemotherapy in breast cancer: results from National Surgical Adjuvant Breast and Bowel Project Protocol B-27.

PURPOSE: Experience with sentinel node biopsy (SNB) after neoadjuvant chemotherapy is limited. We examined the feasibility and accuracy of this procedure within a randomized trial in patients treated with neoadjuvant chemotherapy. PATIENTS AND METHODS: During the conduct of National Surgical Adjuvant Breast and Bowel Project trial B-27, several participating surgeons attempted SNB before the required axillary dissection in 428 patients. All underwent lymphatic mapping and an attempt to identify and remove a sentinel node. Lymphatic mapping was performed with radioactive colloid (14.7%), with lymphazurin blue dye alone (29.9%), or with both (54.7%). RESULTS: Success rate for the identification and removal of a sentinel node was 84.8%. Success rate increased significantly with the use of radioisotope (87.6% to 88.9%) versus with the use of lymphazurin alone (78.1%, P = .03). There were no significant differences in success rate according to clinical tumor size, clinical nodal status, age, or calendar year of random assignment. Of 343 patients who had SNB and axillary dissection, the sentinel nodes were positive in 125 patients and were the only positive nodes in 70 patients (56.0%). Of the 218 patients with negative sentinel nodes, nonsentinel nodes were positive in 15 (false-negative rate, 10.7%; 15 of 140 patients). There were no significant differences in false-negative rate according to clinical patient and tumor characteristics, method of lymphatic mapping, or breast tumor response to chemotherapy. CONCLUSION: These results are comparable to those obtained from multicenter studies evaluating SNB before systemic therapy and suggest that the sentinel node concept is applicable following neoadjuvant chemotherapy.

The effect on tumor response of adding sequential preoperative docetaxel to preoperative doxorubicin and cyclophosphamide: preliminary results from National Surgical Adjuvant Breast and Bowel Project Protocol B-27.

PURPOSE: The National Surgical Adjuvant Breast and Bowel Project Protocol B-27 was designed to determine the effect of adding docetaxel after four cycles of preoperative doxorubicin and cyclophosphamide (AC) on clinical and pathological response rates and on disease-free and overall survival of women with operable breast cancer. PATIENTS AND METHODS: Women (N = 2,411) with operable primary breast cancer were randomly assigned to receive either four cycles of preoperative AC followed by surgery (group I), or four cycles of AC followed by four cycles of docetaxel, followed by surgery (group II), or four cycles of AC followed by surgery and then four cycles of docetaxel (group III). Clinical and pathologic tumor responses to preoperative therapy were assessed. RESULTS: Mean tumor size (4.5 cm) and other key characteristics were evenly balanced among the three treatment arms. Grade 4 toxicity was observed in 10.3% of 2,400 patients during AC treatment, and in 23.4% of 1584 patients during docetaxel treatment. Compared to preoperative AC alone, preoperative AC followed by docetaxel increased the clinical complete response rate (40.1% v 63.6%; P <.001), the overall clinical response rate (85.5% v 90.7%; P <.001), the pathologic complete response rate (13.7% v 26.1%; P <.001), and the proportion of patients with negative nodes (50.8% v 58.2%; P <.001). Pathologic primary breast tumor response was a significant predictor of pathologic nodal status (P <.001). CONCLUSION: The addition of four cycles of preoperative docetaxel after four cycles of preoperative AC significantly increased clinical and pathologic response rates for operable breast cancer.