{"entity":{"id":"nsabp-b04","kind":"trial","name":"NSABP B-04","aka":["National Surgical Adjuvant Breast and Bowel Project B-04","NSABP B04"],"tldr":"The trial that took the radical out of radical mastectomy. Removing the chest muscles and clearing every node did not help women live longer, and neither did removing nodes that had cancer in them but were not causing trouble. It is the first evidence that breast cancer spreads early through the bloodstream rather than marching outward node by node.","summary":"NSABP B-04 opened in 1971 to test William Halsted's theory directly. 1,079 women with clinically negative axillary nodes were randomised three ways, to radical mastectomy, to total mastectomy with postoperative irradiation, or to total mastectomy with axillary dissection only if nodes later became positive. A further 586 women with clinically positive nodes were randomised to radical mastectomy or to total mastectomy with irradiation.\n\nAt twenty-five years there were no significant differences among any of the groups in disease-free survival, relapse-free survival, distant-disease-free survival or overall survival. Among node-negative women, the hazard ratio for death after total mastectomy with radiation against radical mastectomy was 1.08 (95 percent confidence interval 0.91 to 1.28, p=0.38), and after total mastectomy without radiation 1.03 (0.87 to 1.23, p=0.72). Among node-positive women it was 1.06 (0.89 to 1.27, p=0.49).\n\nThe result that matters most is the one about the axilla, and the authors state it plainly: the findings fail to show a significant survival advantage either from removing occult positive nodes at the initial operation or from irradiating them. Differences of a few percentage points cannot be excluded, which is the honest limit of the trial. Every subsequent axillary de-escalation trial, from NSABP B-32 to Z0011 to SENOMAC, is a refinement of the question B-04 asked first.","status":"positive","asOf":"2026-09-25","links":[{"label":"NSABP B-04 twenty-five-year follow-up (New England Journal of Medicine 2002)","url":"https://doi.org/10.1056/NEJMoa020128"}],"tags":[],"related":[],"cancers":["breast-cancer","breast-hr-positive","breast-her2-positive","tnbc"],"sections":[],"technologies":[],"targets":[],"drugs":[],"companies":["nsabp-foundation","nrg-oncology"],"institutions":[],"pathways":[],"terms":["mastectomy","lymphadenectomy","axillary-surgery-de-escalation","post-mastectomy-radiotherapy"],"trials":["nsabp-b06","nsabp-b32","acosog-z0011"],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"phase":"3","setting":"Operable breast cancer: Halsted radical mastectomy against total mastectomy with postoperative irradiation against total mastectomy with axillary dissection only if the nodes became positive, reported at twenty-five years","sponsor":"National Surgical Adjuvant Breast and Bowel Project","result":"No significant difference in disease-free, relapse-free, distant-disease-free or overall survival between radical mastectomy, total mastectomy with irradiation and total mastectomy alone, at twenty-five years.","yearReported":2002,"enrolled":1665,"enrolledBasis":"randomised","enrolledNote":"1,079 women with clinically negative nodes and 586 with clinically positive nodes, 1,665 in all, were randomised from 1971; the trial predates the registries, so there is no registry figure.","outcomes":[{"endpoint":"Death from any cause at 25 years, node-negative women: total mastectomy with radiation against radical mastectomy","primary":true,"unit":"hazard ratio","arms":[{"name":"Total mastectomy with irradiation against radical mastectomy","value":1.08}],"hr":1.08,"ci":[0.91,1.28],"p":"0.38","source":"https://doi.org/10.1056/NEJMoa020128"},{"endpoint":"Death from any cause at 25 years, node-negative women: total mastectomy alone against radical mastectomy","unit":"hazard ratio","arms":[{"name":"Total mastectomy alone against radical mastectomy","value":1.03}],"hr":1.03,"ci":[0.87,1.23],"p":"0.72","source":"https://doi.org/10.1056/NEJMoa020128"},{"endpoint":"Death from any cause at 25 years, node-positive women","unit":"hazard ratio","arms":[{"name":"Total mastectomy with irradiation against radical mastectomy","value":1.06}],"hr":1.06,"ci":[0.89,1.27],"p":"0.49","source":"https://doi.org/10.1056/NEJMoa020128"}],"replication":"NSABP B-06 confirmed that the extent of breast surgery does not change survival; the axillary conclusion was confirmed prospectively by NSABP B-32, ACOSOG Z0011, AMAROS and SENOMAC."},"route":"/trials/nsabp-b04/","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/"}],"company":[{"id":"nrg-oncology","kind":"company","name":"NRG Oncology","route":"/companies/nrg-oncology/"},{"id":"nsabp-foundation","kind":"company","name":"NSABP Foundation","route":"/companies/nsabp-foundation/"}],"term":[{"id":"breast-conserving-surgery-versus-mastectomy","kind":"term","name":"Breast conservation or mastectomy","route":"/terms/breast-conserving-surgery-versus-mastectomy/"},{"id":"axillary-surgery-de-escalation","kind":"term","name":"Doing less to the armpit","route":"/terms/axillary-surgery-de-escalation/"},{"id":"lymphadenectomy","kind":"term","name":"Lymphadenectomy (lymph node dissection)","route":"/terms/lymphadenectomy/"},{"id":"mastectomy","kind":"term","name":"Mastectomy","route":"/terms/mastectomy/"},{"id":"post-mastectomy-radiotherapy","kind":"term","name":"Radiotherapy after mastectomy","route":"/terms/post-mastectomy-radiotherapy/"}],"trial":[{"id":"acosog-z0011","kind":"trial","name":"ACOSOG Z0011 (Alliance)","route":"/trials/acosog-z0011/"},{"id":"nsabp-b06","kind":"trial","name":"NSABP B-06","route":"/trials/nsabp-b06/"},{"id":"nsabp-b32","kind":"trial","name":"NSABP B-32","route":"/trials/nsabp-b32/"}]}}