Mammary gland differentiation and hormonal influences -- Early lesions of the human mammary gland and their relationship to precancerous lesions of other species -- Natural history of benign breast tumors -- Cystosarcoma phyllodes -- Aspiration cytology and cyto-prognosis of breast lesions -- Heterotransplantation of human mammary carcinoma cells -- Human breast tumor cells in culture; new concepts in mammary carcinogenesis -- Elastosis in human breast cancer. Part I. Morphological studies -- Elastosis in human breast cancer. Part II. Biochemical studies -- Fibronectin in breast cancers -- Immunotherapy of spontaneously arising rat mammary tumours -- Morphological aspects of immunotherapy in breast cancer -- Regression in normal and pathological mammary tissues -- The natural history of human breast cancer -- Tumor associated markers in breast cancer -- Contribution of estrogen receptors to the stragegy of breast cancer treatment -- Hormonal dependence of benign breast disease, gynecomastia and breast cancer -- List of invited speakers