The prognosis of infracentimetric breast cancers (BC) is heterogeneous. The EURISTIC survey describes how French oncology specialists perceive the prognosis of pT1a,b pN0 BCs. A self-administered questionnaire has been sent to over 2000 French BC specialists. Six hundred and sixty-three physicians responded. Fifty-eight percent do not consider tumor size as a key prognostic criterion. They consider that the cutoff for poor prognosis is 22mm, 10mm and 7mm for hormone receptors (HRs)+, HER2+ and triple-negative (TN) tumors respectively. Eighty-three percent of respondents consider that a HR+ pT1a,b tumor has a good prognosis (21% and 8% for HER2+ and TN respectively). Factors perceived as most detrimental are: HER2 overexpression (29% of respondents); HR- (20%); high grade (20%); TN status (14%); high KI67 (5%); presence of lymphovascular invasion (3%); young age (2%) and high mitotic index (1%). For French specialists, immunohistochemical characteristics, in particular hormone and HER2 status, are strong prognostic factors in BCs below 1cm.