Several morbidity reports of randomized trials comparing traditional axillary lymph node dissection (ALND) with sentinel lymph node dissection (SLND) followed by ALND for those with pathologically positive sentinel nodes have appeared in the literature over the last few years [1
]. The Sentinel Node Biopsy versus Axillary Clearance (SNAC) study randomized 1088 patients and included as trial outcomes arm volume assessments estimated using a truncated cone approach, shoulder abduction using a goniometer, a variety of patient reports of arm symptoms and quality of life measures collected at baseline prior to surgery and at 3 and 6 months after surgery [1
]. The Italian GIVOM trial randomized 749 patients and included trial outcomes such as arm volume assessment using a truncated cone approach, shoulder abduction using a goniometer, a variety of patient reports of arm symptoms and quality of life measures collected at baseline prior to surgery and at 3 and 6 months and annually after surgery [2
]. The ALMANAC trial randomized 1,031 patients and followed patients at 1, 3, 6, and 12 months with assessment of arm swelling with the sum of conical sections and self-reported arm numbness as part of their quality of life measure [3
]. The Cambridge Breast Unit reported on a small randomized study of 298 patients who had assessments of sensory loss and paresthesia obtained preoperatively and at 1, 3, 6, and 12 months after surgery [5
]. An early report from Italy described a randomized trial of 516 patients with follow-up interviews among a subset of 200 patients at 12 and 24 months after surgery to obtain data on pain, numbness or paresthesia, arm mobility restriction and measured arm circumferences for swelling [6
]. These studies concluded that SLND resulted in less morbidity compared to ALND although the study morbidity effect sizes appeared to vary due to differing samples sizes and follow-up durations as well the inclusion in the SLND group of both sentinel node negative patients and sentinel node positive patients who received axillary dissection. In addition, most of these studies utilized the sum of truncated conical sections to approximate arm volumes in contrast to the more precise water immersion approach to quantify arm swelling used in the current report.
The primary objectives of the NSABP B-32 trial are a comparison of survival, regional control and morbidity endpoints between SLND and ALND treatment groups among clinically node negative women with operable invasive breast cancer [7
]. The definitive comparison of survival and regional control endpoints remain a focus of a future report. Details of the B-32 trial technical success rates for identification of sentinel lymph nodes as well as false negative rates have been reported [8
]. This report will focus on the three year longitudinal characterization and comparison of the following morbidity outcomes between the SLND and ALND treatment groups in patients with pathologically negative sentinel nodes: shoulder range of motion, arm swelling, altered sensations and the incidence of residual morbidity. The morbidity results are based upon the longest follow-up of patients to date from the largest definitive U.S. Phase III trial comparing SLND and ALND treatment groups.