Thanks for using doctors spring services. I understand your problem and will answer your queries to the best possible. Polyp's mainly familial polyposis coli is a premalignant condition for colon cancer. Symptoms of colon cancer usually present with abdominal pain, bleeding per rectum, weight loss, change in bowel habits.
As you have described features probably suggestive of colon cancer, I would recommend you to get further tests to confirm the diagnosis. These include fecal occult blood test, sigmoidoscopy, Colonoscopy-Biopsy of the polyp, CT scan abdomen, blood tests like liver function test, Carcinoembryonic antigen (CEA) which is a tumor marker which is elevated in case of colon cancer. You can consult your doctor with these reports and he should be able to give you the best possible treatment. Hope this helps. If you have any further queries you can always drop me a mail.