Frequency of chronic toxicity from different treatments for rectal cancer
| Symptoms | Surgery alone | Preoperative radiotherapy | Postoperative radiotherapy |
| Any incontinence | 5–38% | 51–72% | 49–60% |
| Toilet dependency | 6% | 30% | 53% |
| Loose stool | 2–5% | N/A | 25–29% |
| Bowel obstruction | 4–11% | 5–13% | 11–15% |
| Excellent bowel function | 32% | 14% | N/A |
Data compiled from a number of references.80–93