What is the difference between colon cancer and irritable bowel syndrome?

IBS has no lesion. Irritable bowel syndrome (IBS) or spastic colon is characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits. Including Diarrhea or constipation. Compared to colon canceer which can present with similar features IBS has no specific lesion causing the symptoms .It has been theorised that abnormalities in GUT flora (microbiome) result in inflammation and altered bowel function. Any bowel lesion causing the symptoms can be identified on colonoscopy.