Table 1.
Preoperative characteristics of patients with low rectal cancer
| Characteristics | Underweight (n = 53) |
Normal weight (n = 589) |
Overweight (n = 336) | Obesity (n = 61) | P value |
|---|---|---|---|---|---|
| Age (years), No. (%) | 0.392 | ||||
| < 50 | 17 (32.1) | 132 (22.4) | 79 (23.5) | 12 (19.7) | |
| ≥ 50 | 36 (67.9) | 457 (77.6) | 257 (76.5) | 49 (80.3) | |
| BMI (kg/m2), median (IQR) | 17.39 (16.65,18.03) | 21.55 (20.52,22.76) | 25.39 (24.57,26.4) | 29.07 (28.45,30.10) | < 0.001 |
| Sex, No. (%) | 0.246 | ||||
| Female | 28 (52.8) | 238 (40.4) | 128 (38.1) | 25 (41.0) | |
| Male | 25 (47.2) | 351 (59.6) | 208 (61.9) | 36 (59.0) | |
| ECOG performance status, No. (%) a | 0.023 | ||||
| 0 | 36 (67.9) | 460 (78.2) | 244 (72.6) | 45 (73.8) | |
| 1 | 15 (28.3) | 123 (20.9) | 92 (27.4) | 16 (26.2) | |
| 2 | 2 (3.8) | 5 (0.9) | 0 (0) | 0 (0) | |
| ASA score, No. (%) | 0.021 | ||||
| I | 38 (71.7) | 441 (75.0) | 225 (67.0) | 38 (62.3) | |
| II | 13 (24.5) | 139 (23.6) | 108 (32.1) | 108 (37.7) | |
| III | 2 (3.8) | 8 (1.4) | 3 (0.9) | 0 (0) | |
| Comorbidity, No. (%) | 17 (32.1) | 149 (25.3) | 102 (30.4) | 13 (21.3) | 0.214 |
| Tumor distance from the anal verge (mm), median (IQR) b | 50 (40, 65) | 50 (40, 60) | 50 (40, 60) | 44.5 (32.5, 60) | 0.140 |
| Tumor distance from the dentate line (mm), median (IQR) c | 40 (20, 50) | 30 (20, 40) | 35 (20, 45) | 30 (20, 40) | 0.084 |
| Preoperative CEA (U/ml) | |||||
| ≤ 5 | 45 (84.9) | 485 (82.3) | 283 (84.2) | 52 (85.2) | 0.721 |
| > 5 | 8 (15.1) | 85 (14.4) | 43 (12.8) | 6 (9.8) | |
| Unknown | 0 | 19 (3.2) | 10 (3.0) | 3 (4.9) | |
| Preoperative CA199 (U/ml) | 0.232 | ||||
| ≤ 37 | 53 (100) | 541 (91.9) | 312 (92.9) | 58 (95.1) | |
| > 37 | 0 | 28 (4.8) | 12 (3.6) | 0 | |
| Unknown | 0 | 20 (3.4) | 12 (3.6) | 3 (4.9) | |
| Clinical TNM stage, No. (%) d | 0.408 | ||||
| I | 20 (37.7) | 224 (38.0) | 111 (33.0) | 25 (41.0) | |
| II/III | 33 (62.3) | 365 (62.0) | 225 (67.0) | 36 (59.0) | |
| Preoperative therapy, No. (%) d | 0.510 | ||||
| Chemoradiotherapy | 33 (100) | 351 (96.2) | 216 (96.0) | 34 (94.4) | |
| Radiotherapy alone | 0 | 1 (0.3) | 0 | 0 | |
| Chemotherapy alone | 0 | 2 (0.5) | 0 | 1 (2.8) | |
| Preoperative therapy, No. (%) d | 33 (100) | 354 (97.0) | 216 (96.0) | 35 (97.2) | 0.819 |
Abbreviations: BMI, body mass index; IQR, interquartile range; ECOG, Eastern Cooperative Oncology Group; ASA, American Society of Anesthesiologists; CEA, Carcinoembryonic Antigen; CA199, Carbohydrate Antigen 199.
a Data were obtained from 1038 patients.
b Data were obtained from 1034 patients.
C Data were obtained from 1034 patients. Tumors that invaded the dentate line.
in 5 patients were excluded.
d Only patients with clinical stage II/III disease were included.