COL1A1 and invasive ductal breast carcinoma: LC-MALDI TOF/TOF MS analysis, corroborated with iTRAQ data for 22 isoforms of collagen type I alpha-1 chain (COL1A1), indicated an increase in fibrillary collagens in invasive ductal carcinoma (IDC) compared with little change in expression in fibroadenoma (FA) or ductal carcinoma in situ (DCIS) [97].