Hemorrhoids, as I mentioned earlier, are generally a benign condition and in and of themselves do not predispose a patient to developing colon cancer. However, patients who experienced blood per rectum may be confused, oftentimes attributing the blood to hemorrhoids. Since hemorrhoids are blood vessels, veins, which can easily bleed. On a similar fashion, a tumor or a cancer in the rectum can also bleed. And so, basically the patient sees blood per rectum and may be confused. So to answer your question, quite simply, hemorrhoids don’t cause cancer, but rectal bleeding may be a sign of hemorrhoids. It may also be a sign of colon cancer.