Comparing patients' and clinicians' assessment of outcomes in a randomised trial of sentinel node biopsy for breast cancer (the RACS SNAC trial).

The RACS sentinel node biopsy versus axillary clearance (SNAC) trial compared sentinel-node-based management (SNBM) and axillary lymph-node dissection (ALND) for breast cancer. In this sub study, we sought to determine whether patient ratings of arm swelling, symptoms, function and disability or clinicians' measurements were most efficient at detecting differences between randomized groups, and therefore, which of these outcome measures would minimise the required sample sizes in future clinical trials. 324 women randomised to SNBM and 319 randomised to ALND were included.