 [ Symptoms ] my legs and feet have been swollen for a week or so and i am very fatigued can you tell me why i recently had blood work done and brought up this problem to my dr but it seems to be getting worse as the days go on especially the swelling of my lower legs ankles and feet [ Disease ] i do not know anything about you or your medical history to tell you your chances that this blood is due to colon cancer but that is the reason this simple test is done there are many reasons why this test would be positive other than cancer but when you have a positive test your medical provider will need to do a very careful diagnostic work up to determine the source of the blood it could be from your stomach your colon a hemorrhoid an anal fissure tear or from eating a lot of red blood containing meat do not be alarmed but it is very important to get to the bottom no pun intended of this positive test