Table 1.
Clinical, Pathologic, and Treatment-Related Characteristics of Patients in Group A (≤8 weeks between completion of nCRT and surgery) and Group B (> 8 weeks)
| Characteristic | Group A n=66 |
Group B n=26 |
p-value |
|---|---|---|---|
| Gender | 0.49 | ||
| Female | 25 (38%) | 12 (46%) | |
| Male | 41 (62%) | 14 (54%) | |
| Median age(range) | 59 (22–84) | 59 (30–88) | 0.48 |
|
Pre-treatment CEA > 5ng/mL |
19 (29%) | 12 (45%) | 0.26 |
|
Pre-treatment CEA >10 ng/mL (mean) |
13 (19%) | 8 (30%) | 0.52 |
|
RT dose > 50.4 Gray (median) |
13 (20%) | 7 (27%) | 0.55 |
| cT stage | 0.16 | ||
| 1–2 | 12 (18%) | 1 (4%) | |
| 3–4 | 54 (82%) | 25 (96%) | |
| cN stage | 0.14 | ||
| 0 | 37 (56%) | 20 (76%) | |
| 1–2 | 29 (44%) | 6 (24%) | |
| pT stage | 0.19 | ||
| 1–2 | 31 (47%) | 7 (28%) | |
| 3–4 | 35 (53%) | 19 (72%) | |
| pN stage | 0.64 | ||
| 0 | 42 (63%) | 15 (58%) | |
| 1–2 | 24 (37%) | 11 (42%) | |
| Risk Groupings | 0.31 | ||
| Low + Intermediate (LI) | 44 (67%) | 14 (52%) | |
| Moderately-high + High (MHH) |
22 (33%) | 12 (48%) | |
|
Pathologic complete response |
12 (18%) | 4 (15%) | 1.0 |
| R1/CM | 15 (23%) | 5 (18%) | 0.76 |
| Location of tumor | 0.58 | ||
| Low (≤5 cm from anal verge) |
23 (35%) | 6 (23%) | |
| Mid/Upper (>5 cm from anal verge) |
29 (44%) | 11 (42%) | |
| Unknown | 14 (21%) | 9 (35%) | |
| Type of resection | 0.21 | ||
| Low anterior | 40 (60%) | 11 (42%) | |
| Abdominoperineal | 21 (32%) | 12 (46%) | |
| Other | 3 (5%) | 3 (12%) | |
| Unknown | 2 (3%) | 0 (0%) | |
| Adjuvant chemotherapy | 1.0 | ||
| Yes | 40 (61%) | 16 (62%) | |
| FOLFOX | 18 | 9 | |
| Capecitabine | 10 | 3 | |
| XELOX | 4 | 2 | |
| Unknown | 8 | 2 | |
| No | 16 (24%) | 6 (23%) | |
| Unknown | 10 (15%) | 4 (15%) |
Abbreviations: CEA= carcinoembryonic antigen; cT=clinical tumor stage; cN=clinical nodal stage; pT= pathologic tumor stage; pN= pathologic nodal stage; R1/CM= microscopically positive or close margin; XELOX= capecitabine, oxaliplatin; FOLFOX= leucovorin, fluorouracil, oxaliplatin