Different factors affect a person's prognosis. Some of the most important are the type and location of the cancer, the extent to which the cancer has metastasized, or spread and how abnormal the cancer cells look and how quickly the cancer is likely to grow and spread. In addition, for cancers of the blood or bone marrow such as leukemias and lymphomas, the presence of chromosomal abnormalities and abnormalities in the patient's complete blood count can affect a person's prognosis. Researchers usually give survival statistics as rates. The rates describe the percentage of people with a specific cancer type who will be alive a certain time after diagnosis. Survival rates can describe any given length of time.