Breast cancer is one of the most prevalent malignancies worldwide, particularly in females, with a high rate of cancer-related deaths globally. Increasing age, obesity, harmful use of alcohol, family history of breast cancer, starting age of menstrual periods, and tobacco use are some of the risk factors for breast cancer. The fifth volume of the “Interdisciplinary Cancer Research” series, entitled “Breast Cancer Pathophysiology: An Interdisciplinary Approach” publishes comprehensive volumes on the mechanisms of breast cancer, early detection, assessment, and patient outcome. The role of defective estrogen signals, membrane estrogen receptor, and dietary polyunsaturated fatty acids in breast cancer are also presented in this volume. This interdisciplinary series is of special value to researchers working on cell biology, immunology, biochemistry, genetics, and practitioners working on oncology. This is the main concept of Cancer Immunology Project (CIP), which is a part of Universal Scientific Education and Research Network (USERN). This interdisciplinary book will be of special value to researchers, oncologists, and oncosurgeons who wish to extend their knowledge on breast cancer.