Your doctor may refer you for blood tests such as:
Complete blood count (CBC) measures the number of red, white, and other blood cells to ensure proper bone marrow function. It also gauges whether treatment is affecting blood cell counts.
Serum chemistry test evaluates levels of electrolytes, such as calcium and potassium, and certain enzymes (proteins). Doing so shows how well various organs are functioning. Abnormal levels of these substances can mean that cancer has spread.