The cancer stage refers to cancer's progression and dissemination. The treatment plan to be followed is determined by the stage of cancer. The statistics on survival are also based on the stage of the malignancy.

The TNM system is one of the most widely used cancer staging methods. This approach is based on the size of the tumour (T), the status of the lymph nodes (N), and the spread or metastasis (M) of cancer, as the name implies. To show the degree of cancer, a number between 0 and 4 is assigned to each of these criteria. The greater the influence of cancer on that element, the higher the number.

An analysis of the tissue taken during surgery determines cancer's pathological stage. This period is often referred to as the surgical stage. If operating on the tumour is not an option, the tumour is given a clinical stage. A physical examination, a biopsy, and imaging studies are used to make this determination.