Throughout your cancer journey, you will likely encounter a large number of tests that aid in the diagnosis, staging or evaluation of disease progression.  These tests may be in the form of a laboratory test, biopsy, radiologic evaluation, endoscopy, etc....  Often, patients are evaluated at the time of their diagnosis and then at defined intervals throughout their treatment plan. 

Below is a link to Cancer.Net, which describes a fair number of diagnostic tests and when they are used.