Table 1 Baseline characteristics of the study groups
Variable | Group | Patient characteristics | |||
|---|---|---|---|---|---|
Total n = 350 | Resection of primary tumor n = 50 | No resection of primary tumor n = 300 | p | ||
Sex | 0.101 | ||||
Female | 145 (41.4%) | 26 (52.0%) | 119 (39.7%) | ||
Male | 205 (58.6%) | 24 (48.0%) | 181 (60.3%) | ||
Race | 0.726 | ||||
White | 278 (79.4%) | 39 (78.0%) | 239 (79.7%) | ||
Black | 40 (11.4%) | 5 (10.0%) | 35 (11.7%) | ||
Other | 32 (9.1%) | 6 (12.0%) | 26 (8.7%) | ||
Age | 0.001 | ||||
< 65 years | 191 (54.6%) | 38 (76.0%) | 153 (51.0%) | ||
≥ 65 years | 159 (45.4%) | 12 (24.0%) | 147 (49.0%) | ||
Grade | 0.284 | ||||
III | 236 (67.4%) | 37 (74.0%) | 199 (66.3%) | ||
IV | 114 (32.6%) | 13 (26.0%) | 101 (33.7%) | ||
Tumor size | < 0.001* | ||||
< 2 cm | 4 (1.1%) | 1 (2.0%) | 3 (1.0%) | 0.872† | |
2–4 cm | 96 (27.4%) | 20 (40.0%) | 76 (25.3%) | ||
> 4 cm | 152 (43.4%) | 28 (56.0%) | 124 (41.3%) | ||
Unknown | 98 (28.0%) | 1 (2.0%) | 97 (32.3%) | ||
Tumor location | < 0.001* | ||||
Head/overlapping | 177 (50.6%) | 23 (46.0%) | 154 (51.3%) | 0.016† | |
Body/tail | 108 (30.9%) | 26 (52.0%) | 82 (27.3%) | ||
Unknown | 65 (18.6%) | 1 (2.0%) | 64 (21.3%) | ||
Lymph node metastases | < 0.001* | ||||
No | 14 (4.0%) | 8 (16.0%) | 6 (2.0%) | 0.078† | |
Yes | 46 (13.1%) | 37 (74.0%) | 9 (3.0%) | ||
Unknown | 290 (82.9%) | 5 (10.0%) | 285 (95.0%) | ||
Chemotherapy | 0.017 | ||||
No | 129 (36.9%) | 26 (52.0%) | 103 (34.3%) | ||
Yes | 221 (63.1%) | 24 (48.0%) | 197 (65.7%) | ||
Year of diagnosis | 0.099 | ||||
< 2010 | 212 (60.6%) | 25 (50%) | 187 (62.3%) | ||
≥ 2010 | 138 (39.4%) | 25 (50%) | 113 (37.7%) | ||