{"entity":{"id":"sound","kind":"trial","name":"SOUND (Sentinel Node vs Observation After Axillary Ultra-Sound)","aka":["SOUND trial"],"tldr":"SOUND went one step further than every trial before it and asked whether the armpit needs to be operated on at all when the tumour is small and the scan is clear. For those women it does not: almost everyone was free of distant spread at five years either way.","summary":"SOUND randomised 1,463 women of any age in Italy, Switzerland, Spain and Chile between 2012 and 2017 who had a breast cancer of up to 2 cm and a negative preoperative axillary ultrasound, to sentinel node biopsy or to no axillary surgery. 1,405 were analysed by intention to treat. The median tumour was 1.1 cm and 87.8 percent were oestrogen receptor-positive and HER2-negative. In the sentinel node arm, 97 patients (13.7 percent) turned out to have positive nodes, which is the size of the staging information the other arm gave up.\n\nAt a median 5.7 years, five-year distant disease-free survival was 97.7 percent with sentinel node biopsy and 98.0 percent without axillary surgery (log-rank p=0.67, hazard ratio 0.84, 90 percent confidence interval 0.45 to 1.54, non-inferiority p=0.02). Locoregional relapses were 12 (1.7 percent) against 11 (1.6 percent), distant metastases 13 against 14, and deaths 21 (3.0 percent) against 18 (2.6 percent).\n\nThe trial attaches a condition that is often dropped when it is quoted: patients can be spared axillary surgery whenever the lack of pathological nodal information does not change the postoperative treatment plan. Where nodal status would decide chemotherapy, radiotherapy fields or the choice of endocrine agent, the information still has to come from somewhere.","status":"positive","asOf":"2026-09-25","links":[{"label":"ClinicalTrials.gov NCT02167490","url":"https://clinicaltrials.gov/study/NCT02167490"},{"label":"SOUND (JAMA Oncology 2023)","url":"https://doi.org/10.1001/jamaoncol.2023.3759"}],"tags":[],"related":[],"cancers":["breast-cancer","breast-hr-positive","breast-her2-positive","tnbc"],"sections":[],"technologies":["sentinel-node"],"targets":[],"drugs":[],"companies":[],"institutions":["ieo-milan"],"pathways":[],"terms":["sentinel-lymph-node-biopsy","axillary-surgery-de-escalation","breast-cancer-related-lymphoedema"],"trials":["insema","nsabp-b32"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"nct":"NCT02167490","phase":"3","setting":"Breast cancer up to 2 cm with a negative preoperative axillary ultrasound: sentinel node biopsy against no axillary surgery at all, with five-year distant disease-free survival as the primary endpoint and a non-inferiority design","sponsor":"European Institute of Oncology, Milan","result":"Five-year distant disease-free survival 98.0 percent without axillary surgery against 97.7 percent with sentinel node biopsy (hazard ratio 0.84, non-inferiority p=0.02).","yearReported":2023,"enrolled":1463,"enrolledBasis":"randomised","enrolledNote":"1,463 women were randomised and 1,405 were analysed by intention to treat; the ClinicalTrials.gov record NCT02167490 gives an estimated 1,560.","outcomes":[{"endpoint":"Distant disease-free survival at 5 years","primary":true,"unit":"%","arms":[{"name":"No axillary surgery","n":697,"value":98},{"name":"Sentinel lymph node biopsy","n":708,"value":97.7}],"hr":0.84,"ci":[0.45,1.54],"p":"0.02 for non-inferiority","source":"https://doi.org/10.1001/jamaoncol.2023.3759"}],"replication":"INSEMA reached the same conclusion in 4,858 patients with T1 and T2 tumours and a longer median follow-up of 73.6 months."},"route":"/trials/sound/","neighbours":{"cancer":[{"id":"breast-cancer","kind":"cancer","name":"Breast cancer (all types)","route":"/cancers/breast-cancer/"},{"id":"breast-her2-positive","kind":"cancer","name":"HER2-positive breast cancer","route":"/cancers/breast-her2-positive/"},{"id":"breast-hr-positive","kind":"cancer","name":"HR-positive / HER2-negative breast cancer","route":"/cancers/breast-hr-positive/"},{"id":"tnbc","kind":"cancer","name":"Triple-negative breast cancer (TNBC)","route":"/cancers/tnbc/"}],"technology":[{"id":"sentinel-node","kind":"technology","name":"Sentinel lymph node biopsy","route":"/technologies/sentinel-node/"}],"institution":[{"id":"ieo-milan","kind":"institution","name":"IEO (European Institute of Oncology)","route":"/institutions/ieo-milan/"}],"term":[{"id":"axillary-surgery-de-escalation","kind":"term","name":"Doing less to the armpit","route":"/terms/axillary-surgery-de-escalation/"},{"id":"breast-cancer-related-lymphoedema","kind":"term","name":"Lymphoedema after breast cancer treatment","route":"/terms/breast-cancer-related-lymphoedema/"},{"id":"sentinel-lymph-node-biopsy","kind":"term","name":"Sentinel node biopsy","route":"/terms/sentinel-lymph-node-biopsy/"}],"trial":[{"id":"insema","kind":"trial","name":"INSEMA (Intergroup Sentinel Mamma)","route":"/trials/insema/"},{"id":"nsabp-b32","kind":"trial","name":"NSABP B-32","route":"/trials/nsabp-b32/"}]}}