Blood in the stool may be the only symptom of colorectal cancer, but not all blood in the stool is caused by cancer. Other conditions that can cause blood in the stool include:
- Hemorrhoids
- Anal fissures
- Colon polyps
- Peptic ulcers
- Ulcerative colitis
- Gastroesophageal reflux disease (GERD)
- Crohn's disease
- Use of aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs)