Although the normal-like subtype has been associated with lower tumor cellularity at surgery, the presence of luminal A tumors fits with the observed increased expression of ESR1 and PGR, and decreased expression of proliferation-related genes like CCNB1 and MKI67. Whether this is due to changes in the biology of tumor cells at baseline or to selection of clones by NAC cannot be addressed herein and remains unknown. The gene discussed is CCNB1; the disease is neoplasm.