Title Page
Contents
ABSTRACT 9
Ⅰ. Introduction 11
Ⅱ. Methods 13
2.1. Patients 13
2.2. Selection of test image sets 15
2.3. Standard of Reference 15
2.4. MRI examinations 15
2.5. CT examinations 16
2.6. Image Analysis 17
2.6.1. Viable rectal cancer 17
2.6.2. Viable regional or distant lymph node metastasis 18
2.6.3. Liver metastasis 18
2.6.4. Incidental malignant lesion 18
2.6.5. Per-patient evaluation 19
2.6.6. Per-lesion evaluation 19
2.7. Outcome 19
2.8. Statistical analysis 19
Ⅲ. Results 21
3.1. Patient characteristics 21
3.2. Viable lesion characteristics 23
3.3. Per-patient diagnostic performance 25
3.3.1. Overall disease evaluation 27
3.3.2. Rectal cancer evaluation 29
3.3.3. Regional lymph node evaluation 29
3.3.4. Distant disease evaluation 29
3.3.5. Supplementary analysis with full sequence liver MRI 29
3.4. Per-lesion diagnostic performance 31
3.5. Interobserver agreement 35
Ⅳ. Discussion 36
Ⅴ. Conclusion 40
References 41
Appendix 46
[Appendix 1] Noncontrast rectal MRI and Gadoxetic acid-enhanced liver MRI acquisition 46
[Appendix 2] Abdominal contrast-enhanced CT acquisition 50
[Appendix 3] Detailed per-patient diagnostic performance by each reviewer (Supplementary Table S2) 51
Abstract (in Korean) 53
〈Table 1〉 Patient characteristics 22
〈Table 2〉 Viable lesion characteristics 24
〈Table 3〉 Diagnostic performance, on per-patient basis 26
〈Table 4〉 Diagnostic performance of liver MRI: abbreviated MRI versus full sequence MRI 30
〈Table 5〉 Diagnostic performance, on per-lesion basis 32
〈Table 6〉 Interobserver agreement on per-patient basis diagnosis 35
〈Figure 1〉 Patient flowchart 14
〈Figure 2〉 Images of a 62-year-old man undergoing a watch-and-wait approach after the completion of neoadjuvant chemoradiotherapy for rectal cancer 28
〈Figure 3〉 Images of a 76-year-old man who underwent preoperative restaging evaluation for rectal cancer after neoadjuvant chemoradiotherapy 33
〈Figure 4〉 Images of a 67-year-old woman who underwent post-treatment follow-up imaging after endoscopic mucosal resection for rectal cancer 34