Would bleeding associated with bowel cancer or small cancer get worse over time?

Sometimes. Sometimes bowel cancers bleed, but not always, and they may or may not get worse. If you are concerned please see your oncologist or gastroenterologist to discuss.
Probably, but... If one is having lower or upper GI bleeding, then an evaluation is in order, which could include upper and lower GI endoscopy. See your doctor, and describe your concerns. Good luck.

Related Questions

Is bleeding from the butt a sign of bowel cancer?

Maybe. Bleeding should be evaluated. It may be something such as ulcers in the stomach or hemorrhoids. However, bleeding could be a sign of colon cancer. This may need a gastroenterology (GI) doctors evaluation. Read more...
Can be. It can be caused by variety of things- including cancer. Nobody knows for sure unless you go to see your doctor and have it checked. One thing is for sure, however, that you would need to have a trip to go to see your gastroenterologist for a GI work-up ( colonoscopy and +/- an endoscopy if warranted. ). Read more...

Would bowel cancer alter blood tests? Abdo pain, rectal bleeding and back ache for 12 mnths. Dr won't refer for colonoscopy as I'm 27 + blood test ok

See different doctor. Rectal bleeding warrants investigation. It is unlikely that you have colon cancer and colonoscopy is probably not required, however, you still need to be evaluated for the cause of rectal bleeding. It may be hemorrhoids, even that needs to be treated. If your current doctor is providing satisfactory care, it is reasonable to see another doctor. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Read more...