Axillary treatment for operable primary breast cancer

Background Axillary surgery is an established part of the management of primary breast cancer. It provides staging information to guide adjuvant therapy and potentially local control of axillary disease. Several alternative approaches to axillary surgery are available, most of which aim to spare a proportion of women the morbidity of complete axillary dissection. Objectives To assess the benefits and harms of alternative approaches to axillary surgery (including omitting such surgery altogether) in terms of overall survival; local, regional and distant recurrences; and adverse events. Search methods We searched the Cochrane Breast Cancer Group Specialised Register, MEDLINE, Pre‐MEDLINE, Embase, CENTRAL, the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov on 12 March 2015 without language restrictions. We also contacted study authors and checked reference lists. Selection criteria Randomised controlled trials (RCTs) including women with clinically defined operable primary breast cancer conducted to compare axillary lymph node dissection (ALND) with no axillary surgery, axillary sampling or sentinel lymph node biopsy (SLNB); RCTs comparing axillary sampling with SLNB or no axillary surgery; RCTs comparing SLNB with no axillary surgery; and RCTs comparing ALND with or without radiotherapy (RT) versus RT alone. Data collection and analysis Two review authors independently assessed each potentially relevant trial for inclusion. We independently extracted outcome data, risk of bias information and study characteristics from all included trials. We pooled data according to trial interventions, and we used hazard ratios (HRs) for time‐to‐event outcomes and odds ratios (OR) for binary outcomes. Main results We included 26 RCTs in this review. Studies were at low or unclear risk of selection bias. Blinding was not done, but this was only considered a source of bias for outcomes with potential for subjectivity in measurements. We found no RCTs of axillary sampling versus SLNB, axillary sampling versus no axillary surgery or SLNB versus no axillary surgery. No axillary surgery versus ALND Ten trials involving 3849 participants compared no axillary surgery versus ALND. Moderate quality evidence showed no important differences between overall survival of women in the two groups (HR 1.06, 95% confidence interval (CI) 0.96 to 1.17; 3849 participants; 10 studies) although no axillary surgery increased the risk of locoregion