The condition usually starts as a benign tumor. However, over time, the tumor has a higher chance of becoming malignant. The stool guaiac test is the most common screening device and, being non-invasive, is commonly performed as part of a regular check-up for any patient over the age of 50. If the test is positive, the patient is usually scheduled for a colonoscopy. If a polyp is found, it is usually routinely removed and, if found to be malignant, the patient will be scheduled for radiology to see if the disease has spread.