Provided herein according to some aspects is a method for processing a tissue sample from a subject, the sample comprising cells of a breast tissue site comprising or suspected of comprising ductal carcinoma in situ (DCIS), and detecting an expression level of a plurality of genes in the cells. Also provided according to some aspects is a method for generating a classifier capable of determining a risk of DCIS recurrence and / or progression. Further provided is a system for determining the risk of DCIS recurrence and / or progression in a subject in need thereof.