Biopsy method and excision volume do not affect success rate of subsequentsentinel lymph node dissection in breast cancer

Introduction: Sentinel lymph node dissection (SLND) is becoming a recognize d technique for accurately staging patients with breast cancer. Its success in patients with large tumors or prior excisions has been questioned. The purpose of this study was to evaluate the effect of biopsy method, excision volume, interval from biopsy to SLND, tumor size, and tumor location on SL ND success rate. Methods: Consecutive patients who underwent SLND followed by completion axi llary lymph node dissection from October 1991 to December 1995 were analyze d. Included were cases performed early in the series before the technique w as adequately developed. Excision volume was derived from the product of th ree dimensions as measured by the pathologist. Two end points were analyzed : sentinel node identification rate and accuracy of SLND in predicting axil lary status. Univariate analyses using chi(2) or Fisher's exact test for ca tegorical variables and Wilcoxon rank sums for continuous variables were pe rformed. Multivariate analysis was performed using logistic regression. Results: There were 284 SLND procedures performed on 283 patients. Median a ge was 55 years. The most recent biopsy method used before SLND was stereot actic core biopsy in 41 (14%), fine-needle aspiration in 62 (22%), and exci sion in 181 (64%) procedures. The mean excision volume was 32 ml with a ran ge of 0.3-169 ml. The mean time from biopsy to SLND was 17 days with a rang e of 0-140 days. The mean tumor size was 2.0 cm (15 Tis [5%], 184 T1 [65%], 72 T2 [25%], and 13 T3 [5%]). Tumors were located in the outer quadrants i n 74%, the inner quadrants in 18%, and subareolar region in 8%. The sentine l node was identified in 81%, and 39% had metastases. There were three fals e-negative cases early in the series. Sensitivity was 97%, and accuracy was 99%. Negative predictive value was 98% in cases in which the sentinel node was identified. On the basis of biopsy method, excisional volume, time fro m biopsy to SLND, tumor size, and tumor location, there was no statisticall y significant difference (P > .05) in sentinel node identification rate or accuracy of SLND. Conclusions: SLND has a high success rate in breast cancer patients regardl ess of the biopsy method or the excision volume removed before SLND. Ln add ition, the interval from biopsy to SLND, tumor size, and tumor location hav e no effect on the success rate of SLND, even in this series which included patients operated on before the technique was adequately defined. Patients with breast cancers located in any quadrant and diagnosed either with a ne edle or excisional biopsy could be evaluated for trials of SLND.