{Reference Type}: Randomized Controlled Trial {Title}: Management of second ipsilateral breast tumor event: An advocacy for a randomized trial. {Author}: Hannoun-Lévi JM;Savignoni A;Féron JG;Malhaire C;Ezzili C;Brédart A;Loap P;Kirova Y; {Journal}: Cancer Radiother {Volume}: 28 {Issue}: 2 {Year}: 2024 Apr 11 {Factor}: 1.217 {DOI}: 10.1016/j.canrad.2023.11.001 {Abstract}: For a second ipsilateral breast tumor event, salvage mastectomy is the standard of care while second conservative treatment is a possible option. However, level 1 proofs are missing, leading to perform salvage mastectomy for patients who could receive second conservative treatment and consequently avoid psychological/quality of life salvage mastectomy deleterious impacts. A phase 3 randomized trial comparing salvage mastectomy to second conservative treatment is needed. Here we discuss what would be to us the optimal design of such trial to confirm the non-inferiority between the two salvage options, with a focus on methodological aspects in terms of patient characteristics and statistical issues.