Copyright information:Taken from "Obesity promotes 7,12-dimethylbenz()anthracene-induced mammary tumor development in female zucker rats"Breast Cancer Research 2005;7(5):R627-R633.Published online 6 Jun 2005PMCID:PMC1242129.Copyright © 2005 Hakkak et al.; licensee BioMed Central Ltd. Intraductal proliferation (intraductal papilloma). Original magnification: 40×. Higher magnification of panel a. Original magnification 200×. Ductal carcinoma . Original magnification: 40×. Higher magnification shows proliferation of uniform neoplastic cells with high nucleus to cytoplasmic ratio within ductal structures. Original magnification: 200×. Invasive ductal carcinoma; arrow shows tumor necrosis in lower left corner. Original magnification: 40×. Higher magnification shows neoplastic cells diffusely infiltrating the stroma. Original magnification: 200×.