Breast cancer may be invasive ductal carcinoma and invasive lobular carcinoma. Risk factors for breast cancer include early menarche, late menopause, intake of hormone replacement therapy after menopause, no breastfeeding, obesity, smoking, alcoholism, genetic factors, radiation therapy to chest and advanced age. Investigations used for diagnosis and staging of disease include mammography, breast biopsy and systemic imaging with CT scan and PET CT scan. Staging of breast cancer is called as TNM staging, it can be clinical or pathological. It can be localised, locally advanced or metastatic disease based on TNM stage. Treatment is decided based on stage, immunohistochemistry and stage of disease. Various treatment options available for breast cancer are surg…