Metastatic cancer. A: The ability to metastasize may require additional mutations after transformation or be present at the time of transformation B: Diagramming the entire genealogy of a cancer reduces the illusion that a metastases should be significantly different from its primary tumor because mutations accumulate throughout life and it is unlikely that a cancer will be asymptomatic for many years. C: Subclassification reduces the relative incidence of each cancer subtype. Equation  may still apply to cancer subtypes without changing the numbers of k rate-limiting pathway mutations by subdividing the mutational target sizes for each subtype. The genes that can be mutated and lead to metastatic cancer may be a smaller subset of the genes that can be mutated and lead to any type of colorectal cancer.