| Astler and Coller Classification | Series | Right-sided colon | Left-sided colon | Rectum | |
| A | 0 | 0% | 0 | 0 | 0 |
| B | 47 | 49% | 17 | 23 | 7 |
| C | 34 | 36% | 11 | 17 | 6 |
| D | 14 | 15% | 6 | 6 | 2 |
| Total | 95 | 100% | 33 | 47 | 15 |