What factors will a doctor consider when choosing cancer treatment for a patient?

Extent and Stage ...: Cancer treatments are tailored to the stage of Cancer which means the extent of Cancer, measured as size of the primary cancer and extent of its spread away from the starting site. Localised cancer(stage-1 and stage-2) are frequently controllable with surgery(operation to remove the tumor) and radiotherapy. Systemic therapies (chemotherapy and modern targeted agents) are used for stages 3-4.