1. CRM (T stage) Low rectal cancer Nodal disease Risk Factors for Loc recurrence

2. Wang et al. Langenbecks Arch Surg 2005; 91: 167-172 Size as a criterium?

3. Based on Wang et al. Langenbecks Arch Surg 2005 Size as a criterium?

4. Lahaye, Beets-Tan et al. Semin US CT MR 2005 AUC 0.96 USPIO MRI Nodal detection

5. > 2 mm </= 2 mm LOCALLY ADVANCED N2N1 NO EARLY TUMOR Distaal Mid rectaal Hoog rectaal NON LOCALLY ADVANCED LOCALLY ADVANCED T3 T1-2 Hoog/mid rectaal DistaalCRM EARLY TUMOR LOCALLY ADVANCED NON LOCALLY ADVANCED BeetsTan, vd Velde, Beets et al. Maastricht MR multicenter study MR stratifies patients into a tailored RX multicenter study

6. LOCALLY ADVANCED EARLY TUMOR NON LOCALLY ADVANCED TME (local excision) 5x5 Gy + TME Chemoradiation + surgery* * 2nd MRI before surgery

7. 2003-2008: n=319 university hospital, 3 regional hospitals Each MRI prospective reading by local radiologist Each MRI double read by expert center: Rx stratification Maastricht MR multicenter study Rx stratification based on MRI prospective multicenter study

8. 2003-2008: n=319 university hospitals, 3 regional hospitals Each MRI prospective reading by local radiologist Each MRI double read by expert center:Rx stratification Loc Recurrence, OS, DFS, death # complete resections Accuracy MRI in expert vs general centers Impact of double reading setting on radiologists performance Maastricht MR multicenter study Rx stratification based on MRI prospective multicenter study

9. 2003-2008: n=319 university hospitals, 3 regional hospitals Each MRI prospective reading by local radiologist Each MRI double read by expert center:Rx stratification Loc Recurrence, OS, DFS, death # complete resections Accuracy MRI in expert vs general centers Impact of double reading setting on radiologists performance Maastricht MR multicenter study Rx stratification based on MRI prospective multicenter study

10. No USPIO GeneralExpert Sens0.620.90 Spec0.830.53 PPV0.620.47 NPV0.830.92 MRI for nodal disease

11. No USPIOWITH USPIO Genera l Expert Genera l Expert Sens 0.620.900.920.95 Spec 0.830.530.690.81 PPV 0.620.470.570.70 NPV 0.830.920.950.97 MRI for nodal disease

12. Maastricht MR multicenter study Conventional MRI not reliable for detection of tumor less than 5 mm Lessons to learn

13. Maastricht MR multicenter study Conventional MRI not reliable for detection of tumor less than 5 mm USPIO MRI selects N0 Lessons to learn

14. Maastricht MR multicenter study Conventional MRI not reliable for detection of tumor less than 5 mm USPIO MRI selects N0 MR stratification also in general hands Lessons to learn

15. Conventional MRI not reliable for detection of tumor less than 5 mm USPIO MRI selects N0 MR stratification also in general hands USPIO not on the market Maastricht MR multicenter study Lessons to learn

16. Maastricht MR multicenter study MS 325 enhanced MRI

17. n= 132 lymph nodes (15/132 N+) Sensitivity 93 % (14/14 +1) Specificity 97 % (113/113+4) PPV 78 % (14/14+4) NPV 99 % (113/113+1) Maastricht MR multicenter study MS 325 MRI for nodal disease