Background: Staging of the axilla in women with ductal carcinoma in situ (DCIS) is a point of controversy. We aimed to assess whether there is a group of patients in whom axillary assessment can be avoided and whether the likelihood of underdiagnosis of infiltrating carcinoma is sufficient to justify this evaluation.
Materials And Methods: This was a multicenter, prospective, observational study of patients who were operated on between 2008 and 2018 in three Spanish hospitals, with a diagnosis by radiological or excisional biopsy of DCIS and clinically and radiologically negative axilla.