Table 1.
Patient demographics in subgroups stratified by histopathological characteristics *.
| Histopathological Characteristics, n (%) | Well 218 (55) |
Moderately 166 (42) |
Poorly 81 (20) |
Signet-Ring 44 (11) |
SCC 32 (8.0) |
|---|---|---|---|---|---|
| Site of cancer, n (%) | |||||
| Esophageal | 2 (0.9) | 4 (2.4) | 0 (0.0) | 0 (0.0) | 32 (100) |
| Gastric | 71 (33) | 85 (51) | 74 (91) | 42 (95) | 0 (0.0) |
| Small intestine | 2 (0.9) | 0 (0.0) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Colorectal | 143 (66) | 77 (46) | 7 (8.6) | 2 (4.6) | 0 (0.0) |
| P-value | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
| Cancer stage, n (%) | |||||
| I | 99 (45) | 63 (38) | 48 (59) | 29 (66) | 4 (13) |
| II | 56 (26) | 49 (30) | 18 (22) | 7 (16) | 15 (47) |
| III | 63 (29) | 54 (33) | 15 (19) | 8 (18) | 13 (41) |
| P-value | 0.31 | 0.38 | 0.002 | 0.003 | 0.001 |
| Intervention, n (%) | |||||
| Vitamin D | 139 (64) | 97 (58) | 45 (56) | 20 (45) | 19 (59) |
| Placebo | 79 (36) | 69 (42) | 36 (44) | 24 (55) | 13 (41) |
| P-value | 0.093 | 0.59 | 0.36 | 0.037 | 0.94 |
| Subgroup of 25(OH)D, n (%) | |||||
| Low: <20 ng/mL | 85 (40) | 66 (40) | 35 (44) | 16 (36) | 20 (65) |
| Middle: ≥ 20 and ≤ 40 ng/mL | 125 (58) | 95 (58) | 45 (56) | 28 (64) | 11 (35) |
| High: >40 ng/mL | 4 (1.9) | 2 (1.2) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| P-value | 0.23 | 0.71 | 0.52 | 0.44 | 0.037 |
| 25(OH)D, median (IQR), ng/mL | 22 (16–27) |
21 (16–27) |
20.5 (15–26) |
22 (16.5–26) |
17 (13–22) |
| P-value | 0.13 | 0.96 | 0.36 | 0.66 | 0.012 |
| Sex, n (%) | |||||
| Male | 144 (66) | 115 (69) | 53 (65) | 26 (59) | 29 (91) |
| Female | 74 (34) | 51 (31) | 28 (35) | 18 (41) | 3 (9.4) |
| P-value | 0.84 | 0.32 | 0.82 | 0.27 | 0.003 |
| Age quartile, n (%) | |||||
| Q1, 35–59 y | 46 (21) | 44 (27) | 27 (33) | 19 (43) | 5 (16) |
| Q2, 60–65 y | 39 (18) | 37 (22) | 22 (27) | 12 (27) | 10 (31) |
| Q3, 66–73 y | 65 (30) | 43 (26) | 16 (20) | 8 (18) | 6 (19) |
| Q4, 74–90 y | 68 (31) | 42 (25) | 16 (20) | 5 (11) | 11 (34) |
| P-value | 0.004 | 0.85 | 0.050 | 0.004 | 0.26 |
| BMI quartile, n (%) | |||||
| Q1, 15.0–19.7 kg/m2 | 46 (21) | 34 (21) | 11 (14) | 11 (25) | 19 (61) |
| Q2, 19.8–21.8 kg/m2 | 55 (25) | 45 (27) | 24 (30) | 12 (27) | 9 (29) |
| Q3, 21.9–23.7 kg/m2 | 54 (25) | 40 (24) | 23 (28) | 8 (18) | 3 (9.7) |
| Q4, 23.8–37.3 kg/m2 | 63 (29) | 46 (28) | 23 (28) | 13 (30) | 0 (0.0) |
| P-value | 0.21 | 0.40 | 0.091 | 0.71 | <0.001 |
| History of other cancers, n (%) | 6 (2.8) | 7 (4.2) | 3 (3.7) | 2 (4.6) | 0 (0.0) |
| P-value | 0.37 | 0.51 | 0.91 | 0.69 | 0.26 |
| Comorbidities, n (%) | |||||
| Hypertension | 92 (42) | 60 (36) | 27 (33) | 10 (23) | 10 (31) |
| P-value | 0.096 | 0.42 | 0.29 | 0.023 | 0.38 |
| Diabetes mellitus | 47 (22) | 24 (14) | 10 (12) | 6 (14) | 0 (0.0) |
| P-value | 0.003 | 0.35 | 0.26 | 0.59 | 0.009 |
| Endocrine disease | 29 (13) | 22 (13) | 10 (12) | 6 (14) | 0 (0.0) |
| P-value | 0.60 | 0.70 | 0.96 | 0.81 | 0.026 |
| Cardiovascular disease | 22 (10) | 12 (7.2) | 6 (7.4) | 2 (4.6) | 1 (3.1) |
| P-value | 0.031 | 0.86 | 0.97 | 0.43 | 0.33 |
| Chronic kidney disease | 3 (1.4) | 2 (1.2) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| P-value | 0.82 | 0.68 | 0.21 | 0.39 | 0.47 |
| Asthma | 3 (1.4) | 2 (1.2) | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| P-value | 0.11 | 0.38 | 0.38 | 0.54 | 0.61 |
| Orthopedic disease | 1 (0.5) | 0 (0.0) | 1 (1.2) | 0 (0.0) | 0 (0.0) |
| P-value | 0.90 | 0.23 | 0.29 | 0.62 | 0.68 |
| Adjuvant chemotherapy, n (%) | 64 (29) | 64 (39) | 25 (31) | 15 (34) | 18 (56) |
| P-value | 0.001 | 0.47 | 0.24 | 0.73 | 0.016 |
* As many patients had multiple histopathological components, histopathological subgroups were not mutually exclusive of each other. Percentages may not equal 100% due to rounding. P-value was calculated by the chi-square test or the Kruskal-Wallis rank test. 25(OH)D, 25-hydroxyvitamin D; BMI, body mass index (weight [kg]/height squared [m2]); IQR, interquartile range; Q1, first quartile; Q2, second quartile; Q3, third quartile; Q4, fourth quartile; Well, well differentiated type of tubular adenocarcinoma; Moderately, moderately differentiated type of tubular adenocarcinoma; Poorly, poorly differentiated adenocarcinoma; Signet-ring, signet-ring cell carcinoma; SCC, squamous cell carcinoma.