This document discusses tumors and cancer, including their aetiology, spread, grading, staging, and management. It covers the epidemiology of various cancer sites by sex. The key risk factors for breast, colorectal, and stomach cancers are outlined. Diagnosis involves clinical history, physical exam, labs, imaging and biopsy. The TNM system is used for clinical staging. Treatment options include surgery, radiation, chemotherapy, and immunotherapy, with goals varying based on cancer extent.