Table 1. Characteristics of all patients (n = 190) and patients matched on propensity scores (n = 100), stratified by treatment type (CTx vs CRT).
| Variable | Entire cohort (n = 190) | Propensity score-matched cohort (n = 100) | |||||
|---|---|---|---|---|---|---|---|
| CTx (n = 136) | CRT (n = 54) | P value | CTx (n = 50) | CRT (n = 50) | P value | ||
| Age | 0.057 | 0.546 | |||||
| ≤ 60 years | 50 (36.8) | 28 (51.9) | 21 (42.0) | 24 (48.0) | |||
| > 60 years | 86 (63.2) | 26 (48.1) | 29 (58.0) | 26 (52.0) | |||
| Sex | 0.066 | 0.822 | |||||
| Female | 56 (41.2) | 14 (25.9) | 14 (28.0) | 13 (26.0) | |||
| Male | 80 (58.8) | 40 (74.1) | 36 (72.0) | 37 (74.0) | |||
| pT stage | 0.782 | 1.000 | |||||
| pT1/2 | 13 (9.6) | 4 (7.4) | 4 (8.0) | 4 (8.0) | |||
| pT3/4 | 123 (90.4) | 50 (92.6) | 46 (92.0) | 46 (92.0) | |||
| pN stage | 0.023* | 0.425 | |||||
| pN0 | 64 (47.1) | 16 (29.6) | 19 (38.0) | 15 (30.0) | |||
| pN1 | 47 (34.6) | 19 (35.2) | 13 (26.0) | 19 (38.0) | |||
| pN2 | 25 (18.4) | 19 (35.2) | 18 (36.0) | 16 (32.0) | |||
| pTNM stage | 0.028* | 0.398 | |||||
| pStage II | 64 (47.1) | 16 (29.6) | 19 (38.0) | 15 (30.0) | |||
| pStage III | 72 (52.9) | 38 (70.4) | 31 (62.0) | 35 (70.0) | |||
| Histologic grade | 0.197 | 1.000 | |||||
| Others | 130 (95.6) | 49 (90.7) | 45 (90.0) | 46 (92.0) | |||
| Poorly differentiated | 6 (4.4) | 5 (9.3) | 5 (10.0) | 4 (8.0) | |||
| Tumor size (cm) | 4.8 (1.0–12.0) | 5.0 (0.2–9.0) | 0.689 | 5.0 (1.0–10.0) | 5.0 (0.2–9.0) | 0.922 | |
| Number of harvested lymph nodes | 27 (7–119) | 26 (12–76) | 0.087 | 28 (7–119) | 25 (12–65) | 0.059 | |
| Preoperative CEA (ng/mL) | 2.5 (0.9–215.0) | 2.1 (0.9–40.0) | 0.382 | 2.7 (0.9–122.3) | 2.1 (0.9–40.0) | 0.325 | |
| Postoperative CEA (ng/mL) | 1.1 (0.3–11.2) | 1.1 (0.5–4.5) | 0.391 | 1.1 (0.8–11.2) | 1.1 (0.5–4.5) | 0.426 | |
| Lymphovascular invasion | 0.031* | 0.839 | |||||
| No | 74 (54.4) | 20 (37.0) | 21 (42.0) | 20 (40.0) | |||
| Yes | 62 (45.6) | 34 (63.0) | 29 (58.0) | 30 (60.0) | |||
| Perineural invasion | 0.976 | 0.391 | |||||
| No | 96 (70.6) | 38 (70.4) | 32 (64.0) | 36 (72.0) | |||
| Yes | 40 (29.4) | 16 (29.4) | 18 (36.0) | 14 (28.0) | |||
| Involved resection margin | <0.001* | 0.183 | |||||
| No | 128 (94.1) | 40 (74.1) | 44 (88.0) | 39 (78.0) | |||
| Yes | 8 (5.9) | 14 (25.9) | 6 (12.0) | 11 (22.0) | |||
| Adjuvant chemotherapy for 6 months | 0.027* | 1.000 | |||||
| No | 22 (16.2) | 2 (3.7) | 2 (4.0) | 2 (4.0) | |||
| Yes | 114 (83.8) | 52 (96.3) | 48 (96.0) | 48 (96.0) | |||
Categorical variables are presented as n (%), continuous variables are presented as median (range).
Abbreviations: CTx = chemotherapy alone; CRT = chemoradiotherapy; CEA = carcinoembryonic antigen.
* Statistically significant.