Sentinel-Lymph-Node-Based Management or Routine Axillary Clearance? One-Year Outcomes of Sentinel Node Biopsy Versus Axillary Clearance (SNAC): A Randomized Controlled Surgical Trial

Abstract

We sought the extent to which arm morbidity could be reduced by using sentinel-lymph-node-based management in women with clinically node-negative early breast cancer. One thousand eighty-eight women were randomly allocated to sentinel-lymph-node biopsy followed by axillary clearance if the sentinel node was positive or not detected (SNBM) or routine axillary clearance (RAC, sentinel-lymph-node biopsy followed immediately by axillary clearance). Sentinel nodes were located using blue dye, alone or with technetium-labeled antimony sulfide colloid. The primary endpoint was increase in arm volume from baseline to the average of measurements at 6 and 12 months. Secondary endpoints were the proportions of women with at least 15% increase in arm volume or early axillary morbidity, and average scores for arm symptoms, dysfunctions, and disabilities assessed at 6 and 12 months by patients with the SNAC Study-Specific Scales and other quality-of-life instruments. Sensitivity, false-negative rates, and negative predictive values for sentinel-lymph-node biopsy were estimated in the RAC group. The average increase in arm volume was 2.8% in the SNBM group and 4.2% in the RAC group (P = 0.002). Patients in the SNBM group gave lower ratings for arm swelling (P < 0.001), symptoms (P < 0.001), and dysfunctions (P = 0.02), but not disabilities (P = 0.5). Sentinel nodes were found in 95% of the SNBM group (29% positive) and 93% of the RAC group (25% positive). SNB had sensitivity 94.5%, false-negative rate 5.5%, and negative predictive value 98%. SNBM was successfully undertaken in a wide range of surgical centers and caused significantly less morbidity than RAC.

Outcome of axillary staging in early breast cancer: a meta-analysis

“…Seven trials were thus eligible, as shown in Table 1 [3,4,[7][8][9][10][11]. A total of 9,608 patients were randomly assigned to treatment (658 in the SNB only arm, 5,084 in the ALND only arm and 4,406 who had SNB and then went onto have ALND), and data was available for analysis from 8,853 of them (636, 4,389 and 3,828 in the three arms, respectively).…”

“…There was little variability among studies in the menopausal status, eligible stages of breast cancer and tumour size of participants. All seven trials enroled patients between 1998 and 2005, and six of the seven studies were multicentre trials [4,[7][8][9][10][11].…”

“…Five trials [3,4,7,9,11] described the method of power calculation, six trials [4,[7][8][9][10][11] described in detail the mode of randomization and five trials [4,[7][8][9]11] described the mode of allocation concealment in detail. Withdrawals were described in detail in six trials [3,4,[8][9][10][11].…”

“…Withdrawals were described in detail in six trials [3,4,[8][9][10][11]. None of the seven studies were blinded.…”

“…In four trials the control group underwent SNB followed by routine ALND and the test group underwent SNB with ALND only if the SNB was positive [3,[8][9][10]. In two trials the control group underwent ALND only and the test group underwent SNB with ALND only if the SNB was positive [4,11]. In these studies, there was no significant difference in the rate of axillary lymph node positivity among clinically node negative patients; 28.8% for ALND and 27.6% for SNB [ALND (n = 4,464) and SNB (n = 4,464) (OR = 1.00, 95% CI = 0.86-1.17, P = 0.956)] [3, 4, 7, 9-11] (Fig.…”