I have been experiencing all or most of the symptoms of colon/colorectal cancer, i.e. narrow stools, bloody mucus from the rectum on several occasions, localized abdominal pain (left flank and area just above the ilica crest), drastic change in bowel movements, significant weight loss (15 lbs in 2 months), loss of appetite, fatigue, etc. etc. etc. for the last 2 or 3 months. However: I am 21 years old, in farily good shape, and without a known family history of colon cancer. I have had symptoms associated with irritable syndrome since age 17, (unexplained abdominal cramping after eating and relief from that discomfort after a bowel movement) but don't think that my current symptoms are associated with IBS. I just saw a gastrointerologist who recommended a colonoscopy (I am having the test done in 3 days) and said it could be something as simple as hemorroidal bleeding, or something as nasty and complex as colon cancer. I know it is highly unusual for someone as young as myself to have the disease, but according to my symptoms it is hard to come up with another explanation. So, with that in mind, I suppose my question is: What are some illnesses (other than colon/colorectal cancer) associated with the symptoms I have been having for the last 2 or 3 months? I don't know how long it takes for someone to respond to these ?'s. I realize that it is likely that I will have my colonoscopy and recieve a diagnosis from my Dr. before I recive a response due to what seems to be a large number of ?'s. However, any response will be greatly appreciated at any time. Thanks.