Finding cancer at its earliest, most treatable stage gives patients the greatest chance of survival. For a number of cancers, screening tests allow for early detection and treatment, and thereby, reduce cancer-related mortality. However, many cancers are discovered by symptomatic presentation rather than screening. This article addresses several symptoms commonly reported in the primary care setting, including rectal bleeding, a breast lump, cough, lymphadenopathy, and weight loss, and offers an evidence-based approach to the consideration and possibly the diagnosis of cancer.