Inclusion criteria
ER-positive, necrosis
DCIS, PATHOLOGY, COMEDO, NECROSIS

New histologically diagnosed breast DCISAge ≥40 yearsLow risks of DCIS must be detected by a mammogram and must be unicentric, with non-mass lesionsStatus post-BCSPathological characteristics:Lesions ≤2.5 cm in the greatest dimension on pathology specimens (use the largest measured size from the pathology report to obtain the required measurement of ≤2.5 cm)Must be classified as low or intermediate nuclear grade DCIS but without comedo or necrosis, according to the Pathologic Guidelines [Margins, as assessed by the ink method, should be ≥ 3 mm.Must be ER-positive DCIS, and the ER percentage must be ≥ 10%Clinically node-negative