Progress in basic research has made it necessary to redetermine the possibility of classic endocrine therapy for the treatment of patients with breast cancer. Exemplary, close cooperation between biochemis try and animal and clinical research led to a truly interdisciplinary and international exchange of ideas and experience at a symposium held in autumn 1978 in Heidelberg. We owe our thanks to ICI-Pharma for the kind support of this sym posIUm. The participation of Charles Huggins in the meeting as honorary chairman signified to all participants the meaning of this joint endeavour. It was the same Charles Huggins who through experimental work laid the foundation stone for endocrine ther apy of prostate and breast cancer, and who applied his findings clinically. Thousands of patients owe to him relief from their suffering. He contributed greatly to the attempt to find and stabilize the endocrine therapy for breast cancer, for which we thank him sincerely. We hope that the following contributions will similarly serve the well-being of our patients.

Inhalt
I. Improved Biochemical Characterization of Breast Cancer.- 1. Improved Biochemical Characterization of Breast Cancer as a Guide to Hormonal Treatment.- 2. Steroid Receptor Determinations in Mammary Carcinoma in Women.- 3. Steroid Receptor Determination by Means of Agar Gel Electrophoresis.- 4. Estrogen Receptor Determination Predicts Response to Tamoxifen Therapy.- 5. Estrogen Receptor Status and the Disease-Free Interval in Breast Cancer.- 6. Clinical Predictive Criteria for Response to Endocrine Treatment and the Receptor Status.- II. Antiestrogens in Experimental Breast Cancer.- 7. Anti-Oestrogen Action in Experimental Breast Cancer.- 8. Studies on Mechanisms of Estrogen and Antiestrogen Action in Human Breast Cancer.- 9. Human Breast Cancer in Nude Mice: A Model for Testing Endocrine Treatment.- 10. A Hormone-Dependent Human Breast Cancer Cell Line Grown in Defined Medium.- 11. Endocrine and Cytostatic Treatment of Experimental Mammary Cancer.- 12. The Direct Inhibition of Prostaglandin Synthetase of Human Breast Cancer Tumour Tissue by Tamoxifen.- III. Endocrine Treatment of Advanced Breast Cancer.- 13. Endocrine Treatment of Advanced Breast Cancer.- 14. Principles and Indications of Endocrine Treatment of Advanced Breast Cancer.- 15. Ablation of the Hypophysis by Radioactive Gold in Metastatic Mammary Carcinoma.- 16. Anti-Oestrogens: An Alternative to Ablative Endocrine Therapy?.- IV. Anti-Oestrogens in the Treatment of Advanced BreastCancer.- 17. Tamoxifen in Advanced Breast Cancer: Experience of the SAKK (Schweizerische Arbeitsgruppe für Klinische Krebsforschung Swiss Cooperative Oncology Group).- 18. Therapeutic Effect of Tamoxifen Related to Estrogen Receptor Level.- 19. Results of Tamoxifen Therapy in Patients with Breast Cancer.- 20. Results withTamoxifen in Advanced Mammary Carcinoma.- 21. The Significance of Tumour Stimulation by Tamoxifen.- V. Combination Therapy of Advanced Breast Cancer.- 22. Simultaneous Hormone- and Chemotherapy, Compared with Hormone Therapy Followed by Chemotherapy in the Treatment of Metastasising Mammary Carcinoma Preliminary Results of a Current Study.- 23. Lack of Estrogen Receptor Associated with an Increased Response Rate to Cytotoxic Chemotherapy in Metastatic Breast Cancer?.- 24. The Influence of Polychemotherapeutic Regimen on the Female Endocrine Control Mechanisms in Mammary Carcinoma Patients.- 25. Therapeutic Effect of Tamoxifen Alone Versus Tamoxifen in Combination with Gestagen and Oestrogen in Advanced Breast Cancer.- VI. Adjuvant Endocrine Therapy of Breast Cancer.- 26. Is There a Place for Adjuvant Endocrine Therapy of Breast Cancer?.- 27. Adjuvant Endocrine Therapy of Breast Cancer A Controlled Clinical Trial of Oestrogen and Anti-Oestrogen: Preliminary Results of the Copenhagen Breast Cancer Trials.- VII. Principles of Clinical Trials.- 28. Principles of Clinical Trials.- 29. Establishment of Uniformity in Steroid Receptor Analyses Used in Cooperative Clinical Trials of Breast Cancer Treatment.- VIII. Anti-Oestrogen Treatment in Breast Cancer A Comprehensive Review.- 30. Clinical Experience with Tamoxifen in Advanced Breast Cancer.- 31. The Place of Tamoxifen in the Treatment of Breast Cancer.- Final Remarks.