Table 2.
Comparison according to country
| Variable | China | Japan | Korea | Others | P-value |
|---|---|---|---|---|---|
| Age (yr) | <0.001 | ||||
| 30–39 | 63 (31.2) | 0 (0) | 19 (23.5) | 8 (14.5) | |
| 40–49 | 98 (48.5) | 26 (32.9) | 33 (40.7) | 22 (40.0) | |
| 50–59 | 37 (18.3) | 40 (50.6) | 21 (25.9) | 16 (29.1) | |
| 60–69 | 4 (2.0) | 13 (16.5) | 8 (9.9) | 8 (14.5) | |
| 70–71 | 0 (0) | 0 (0) | 0 (0) | 1 (1.8) | |
| Colorectal surgeon | 0.830 | ||||
| Yes | 195 (96.5) | 79 (100) | 81 (100) | 52 (94.5) | |
| No | 7 (3.5) | 0 (0) | 0 (0) | 3 (5.5) | |
| Affiliation | 0.046 | ||||
| University or tertiary hospital | 189 (93.6) | 70 (88.6) | 75 (92.6) | 45 (81.8) | |
| Others | 13 (6.4) | 9 (11.4) | 6 (7.4) | 10 (18.2) | |
| Department of Radiation Oncology | 0.073 | ||||
| Yes | 185 (91.6) | 66 (83.5) | 74 (91.4) | 45 (81.8) | |
| No | 17 (8.4) | 13 (16.5) | 7 (8.6) | 10 (18.2) | |
| Acceptance of W&W | <0.001 | ||||
| Yes | 178 (88.1) | 67 (84.8) | 54 (66.7) | 38 (69.1) | |
| No | 24 (11.9) | 12 (15.2) | 27 (33.3) | 17 (30.9) | |
| Experience with W&W in clinical practice | <0.001 | ||||
| Yes | 160 (79.2) | 34 (43.0) | 40 (49.4) | 39 (70.9) | |
| No | 42 (20.8) | 45 (57.0) | 41 (50.6) | 16 (29.1) | |
| Informed consent in case of clinical CR | <0.001 | ||||
| Yes | 174 (86.1) | 48 (60.8) | 55 (67.9) | 46 (83.6) | |
| No | 28 (13.9) | 31 (39.2) | 26 (32.1) | 9 (16.4) | |
| Preferred option in clinical CR | 0.531 | ||||
| W&W, always | 16 (7.9) | 5 (6.3) | 6 (7.4) | 10 (18.2) | |
| W&W, selectively | 163 (80.7) | 62 (78.5) | 63 (77.8) | 38 (69.1) | |
| Radical surgery | 23 (11.4) | 12 (15.2) | 12 (14.8) | 7 (12.7) | |
| Reasons for refusal of W&W (multiple) | |||||
| Inaccuracy of imaging | 167 (82.7) | 57 (72.2) | 55 (67.9) | 45 (81.8) | 0.025 |
| Lack of evidence | 182 (90.1) | 49 (62.0) | 54 (66.7) | 45 (81.8) | <0.001 |
| Personal experience | 7 (3.5) | 3 (3.8) | 5 (6.2) | 2 (3.6) | 0.581 |
| Legal issue | 7 (3.5) | 1 (1.3) | 9 (11.1) | 0 (0) | 0.580 |
| Lack of radiotherapy facility | 2 (1.0) | 3 (3.8) | 0 (0) | 0 (0) | 0.445 |
| Patient refusal | 3 (1.5) | 1 (1.3) | 0 (0) | 3 (5.5) | 0.269 |
| Plan for W&W in the future | <0.001 | ||||
| Yes | 1 (0.5) | 38 (48.1) | 24 (39.4) | 8 (14.5) | |
| No | 2 (1.0) | 7 (8.9) | 17 (21.0) | 6 (10.9) | |
| NA | 199 (98.5) | 34 (43.0) | 40 (49.4) | 41 (74.5) | |
| Restaging methods (multiple) | |||||
| CT | 69 (34.2) | 72 (91.1) | 67 (82.7) | 33 (60.0) | <0.001 |
| MRI | 196 (97.0) | 70 (88.6) | 76 (93.8) | 52 (94.5) | 0.274 |
| Sigmoidoscopy | 122 (60.4) | 68 (86.1) | 65 (80.2) | 38 (69.1) | <0.001 |
| PET-CT | 41 (20.3) | 43 (54.4) | 5 (6.2) | 25 (45.5) | 0.089 |
| Ultrasound | 12 (5.9) | 7 (8.9) | 13 (16.0) | 6 (9.1) | 0.061 |
| Digital rectal examination | 9 (4.5) | 2 (2.5) | 4 (4.9) | 4 (7.3) | 0.455 |
| Doses for radiation | 0.003 | ||||
| <5,040 cGy | 67 (33.2) | 32 (40.5) | 3 (3.7) | 5 (9.1) | |
| 5,040 cGy | 89 (44.1) | 32 (40.5) | 68 (84.0) | 33 (60.0) | |
| 5,400 cGy | 42 (20.8) | 14 (17.7) | 10 (12.3) | 17 (30.9) | |
| >5,040 cGy | 4 (2.0) | 1 (1.3) | 0 (0) | 0 (0) | |
| Chemotherapy regimen | <0.001 | ||||
| 5-Fluorouracil | 25 (12.4) | 14 (17.7) | 30 (37.0) | 29 (52.7) | |
| Capecitabine | 137 (67.8) | 33 (41.8) | 43 (53.1) | 19 (34.5) | |
| Oxaliplatin | 36 (17.8) | 10 (12.7) | 8 (9.9) | 5 (9.1) | |
| Others | 4 (2.0) | 22 (27.8) | 0 (0) | 2 (3.6) | |
| Chemotherapy during the resting period | <0.001 | ||||
| Same regimen of CRT | 90 (44.6) | 19 (24.1) | 11 (13.6) | 7 (12.7) | |
| Different regimen of CRT | 36 (17.8) | 7 (8.9) | 10 (12.3) | 7 (12.7) | |
| None | 76 (37.6) | 53 (67.1) | 60 (74.1) | 41 (74.5) | |
| Interval between CRT and evaluation | 0.009 | ||||
| 4 Weeks | 42 (30.7) | 17 (21.5) | 15 (18.5) | 8 (14.5) | |
| 6 Weeks | 59 (29.2) | 17 (21.5) | 37 (45.7) | 14 (25.5) | |
| 8 Weeks | 74 (36.6) | 40 (50.6) | 28 (34.6) | 30 (54.5) | |
| 10 Weeks | 5 (2.5) | 5 (6.3) | 1 (1.2) | 3 (5.5) | |
| 12 Weeks | 2 (1.0) | 0 (0) | 0 (0) | 0 (0) | |
| >12 Weeks | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Follow-up | 0.031 | ||||
| Every month | 60 (29.7) | 4 (5.1) | 8 (9.9) | 2 (3.6) | |
| Every 2 months | 39 (19.3) | 16 (20.3) | 14 (17.3) | 6 (10.9) | |
| Every 3 months | 62 (30.7) | 56 (70.9) | 49 (60.5) | 42 (76.4) | |
| Every 6 months | 0 (0) | 1 (1.3) | 4 (4.9) | 2 (3.6) | |
| Others | 41 (20.3) | 2 (2.5) | 6 (7.4) | 3 (5.5) | |
| Management for local regrowth | <0.001 | ||||
| Wait and follow-up | 3 (1.5) | 0 (0) | 0 (0) | 0 (0) | |
| Radical surgery | 146 (72.3) | 64 (81.0) | 74 (91.4) | 49 (89.1) | |
| Chemotherapy | 2 (1.0) | 5 (6.3) | 1 (1.2) | 1 (1.8) | |
| Repeat CRT | 9 (4.5) | 0 (0) | 0 (0) | 2 (3.6) | |
| Proton therapy | 0 (0) | 0 (0) | 0 (0) | 0 (0) | |
| Local excision | 0 (0) | 8 (10.1) | 4 (4.9) | 2 (3.6) | |
| Others | 42 (20.8) | 2 (2.5) | 2 (2.5) | 1 (1.8) |
Values are presented as number (%).
W&W, watch-and-wait; CRT, chemoradiotherapy; CR, complete response; CT, computed tomography; MRI, magnetic resonance imaging; PET-CT, positron emission tomography-computed tomography; NA, not applicable.