Do all rectal/colon cancer have bloody or black stool?

No. Microscopic poss. Not all colon cancers cause changes to stool that u can see w/ your eye. Some polyps (pre-cancerous lesions) cause MICROscopic blood in the stool that only sensitive lab tests can pick up. Bright red stool is thought 2 b from rectum, maroon red stool from intestine, & dark / black stool (melena) from stomach; however, it depends on how brisk bleeding is. Slow bleeds may not discolor stool at all.

Related Questions

Is black stool a symptom of colon cancer or ulcer?

Depends. There are many causes of black tarry stool. The common issue is bleeding in the intestine. Bleeding may be due to ulcers in the stomach, or intestine. Oral iron intake may produce dark stool. Colon cancer is one of the causes of bleeding in the intestine. It would be prudent to see your doctor to determine the cause of dark stools, especially if it is due to bleeding in the intestine. Read more...
Ulcer. Bleeding from a tumor of the colon results in the presence of blood in the stool. This blood is for the most part red, but may have signs of some decomposition. When blood is released from a stomach ulcer, the acid that is present breaks the Hgb down to result in a black appearing stool which is not seen is colon malignancies. Read more...
It can be. Black stool is a sign of blood within the GI tract visually from the upper GI tract (stomach and small bowel). It is ALWAYS worth while to get checked out by a gastroenterologist to be certain. . Read more...

What kind of black stool is a indicator of colon cancer? Smelly and tarry? I had dark leafy specks on my stool im 22

Is it colon cancer? Colon cancer is diagnosed under a microscope by a pathologist looking at a piece of your colon. That piece is collected during colonoscopy, where the inside of your colon is visualized, any polyps, or masses are biopsied and sent to path. Your age is low risk. Your dark, tarry stool, is a symptom. If persists, take a sample to your doc, test it for blood, if positive, doc will order colonoscopy. Read more...
Blood. Dark tarry stools is indicative of blood high in the GI tract like a bleeding ulcer. You should talk to your primary care doc about this. May need antacid medicaton. Read more...

Are there other signs of colon cancer besides bloody stools?

Yes. Change in bowel habits, decrease in the diameter of the stool, mucus discharge, weight loss, unexplained anemia, abdominal pain, are among the symptoms of colon cancer. Read more...
Many. Other concerning symptoms include abdomen pain, change in bowel habits (constipation, frequent small stools), weight loss, bloating, nausea, anemia. Read more...