Less Remains Better: Morbidity After Axillary Surgery

It took the best part of 50 years for radical mastectomy to be replaced by mastectomy and subsequently for breastconserving techniques of segmental mastectomy with radiotherapy to be accepted for the majority of patients. Similarly, surgical staging of the axilla has evolved from radical clearance of the axilla with resection of the pectoralis minor muscle through axillary lymph node dissection (ALND) to our current standard of sentinel node biopsy (SNB). We now recognize that appropriately targeted node sampling, preferably with a dual (dye and isotope) technique, is the surgical approach of choice in clinically nodenegative patients with breast cancer. Minimizing axillary surgery should theoretically reduce postoperative complications and long-term morbidity, and trials that prospectively prove this hypothesis and quantify the changes have been increasingly reported in the literature. There are clear benefits in terms of morbidity for SNB over ALND, but neither approach is free of consequences for the patient. Although most studies have, understandably, focused on the short-term morbidities, the Australian and New Zealand community are to be commended in securing follow-up data in [80 % of their patients to 3 years with a consistent and meticulous examination of upper limb morbidity within the SNAC1 trial. The patient population studied probably represents the real world for clinically node-negative breast cancers \3 cm (58 % were screen detected), and the application of validated (on the populations under study) objective and subjective measures up to the 3-year mark is laudable. One strength of the SNAC1 trial is that they included both objective and subjective components to measure evidence of arm swelling, in contrast to the ALMANAC trial, which reported similar subjective results based on the FACT-B?4 instrument, and the NSABP B-32 trial and Italian GIVOM trial, which relied on objective measurements alone. SNAC1 temporally extends the findings that patients who undergo ALND have higher arm volume changes, with more symptoms of arm swelling and disability reported by patients. One concern is the definition of lymphedema—an issue that plagues all investigators attempting to quantify it. The investigators measured arm circumference at 10-cm intervals and report this as a percentage change in volume over preoperative baseline arm measurements. One possible source of measurement bias is that they do not factor contralateral arm circumference in their calculations, as other investigators have done. Weight changes are common after breast cancer therapy and can certainly influence these measurements. Use of contralateral arm volumes may help delineate how much of the change in the affected arm is secondary to therapeutic interventions. Although both ALND and SNB patient groups may be equally likely to gain weight, this might account for half of the patients with a [15 % change over baseline not reporting subjective symptoms of arm swelling. As ever, subjective measures may not concord with the (generally worse) objective measurement of upper limb swelling. An interesting finding of the trial is that there was no particular disadvantage in terms of morbidity to the twostage approach of a positive SNB being followed by a second trip to the operating room for axillary node dissection. The need for a second operation is now questionable in the light of several recent trials, such as ACOSOG Z0011, IBCSG 23-01, and AMAROS, which show no advantage to axillary clearance over SNB alone in clinically node-negative patients found to have small-volume nodal disease. Morbidity has been reported from these trials with findings similar to the SNAC1 trial. It is reasonable that the benefits to SNB alone shown in the Society of Surgical Oncology 2014