Is sentinel lymph node biopsy reliable and indicated after preoperative chemotherapy in patients with breast carcinoma?

BACKGROUND. Many studies support the concept and accuracy of sentinel lymph node biopsy (SNB) for staging patients with breast carcinoma, which can be performed with low morbidity in lymph node negative patient. Preoperative chemotherapy (PC) plays an important role in the treatment of patients with operable breast carcinoma and is another approach with which to reduce rad ical surgery in patients with more advanced disease. It is of interest whet her the sentinel lymph node accurately represents the axillary status after PC and, thus, whether the sentinel node concept can be applied to both gro ups. METHODS. Thirty-three patients underwent SNB after chemotherapy and prior t o axillary lymph node dissection. RESULTS. The average greatest tumor dimension before chemotherapy (33 mm +/ - 2 mm) was significantly larger (P = 0.000) than after therapy (20 mm +/- 3mm). Histopathologic complete remission was seen in only three patients. O ne or two sentinel lymph nodes (average, 1.7 lymph nodes) were identified w ith certainty in 29 of 33 procedures and accurately predicted axillary lymp h node Status in all of these patients. Breast-conserving surgery was possi ble in 21 patients (64%), and axillary lymph nodes were involved in 22 pati ents (67%). CONCLUSIONS. Even after patients undergo PC, SNB seems to be a reliable met hod for accurate staging of the axilla in those more advanced breast carcin oma. Thus, axillary dissection may be avoided in certain patients. Lymph no de involvement seems to be likely in women with suspicious axillary finding s before chemotherapy who have no visible sentinel lymph nodes on preoperat ive lymphosintigraphy and in patients without recurrent tumors. Further inv estigation of the SNB concept in this patient group should be evaluated in larger Studies. . (C) 2001 American Cancer Society.