Updated publication reference for PubMed record(s): 30501643. We generated large-scale proteome data for 65 human breast tumors and 53 paired adjacent non-cancerous tissue and performed an integrated proteotranscriptomic characterization. To our best knowledge, the study is one of the largest quantitative proteomic study of human breast tissues, including the analysis of 118 tissue samples from 65 patients with long-term survival outcomes. Our data show that protein expression describes a tumor biology that is only partly captured by the transcriptome, with mRNA abundance incompletely predicting protein abundance in tumors, and even less so in non-cancerous tissue. Furthermore, the tumor proteome described disease pathways and subgroups that were only partially captured by the tumor transcriptome.