Table 1. The characteristics of the patients.
| Characteristics | Overall (n=3,805) | Testing data set (n=1,141) | Training data set (n=2,664) | P |
|---|---|---|---|---|
| Status (%) | 1 | |||
| 0 | 1,290 (33.9) | 387 (33.9) | 903 (33.9) | |
| 1 | 411 (10.8) | 123 (10.8) | 288 (10.8) | |
| 2 | 2,104 (55.3) | 631 (55.3) | 1,473 (55.3) | |
| Time (months), [median (IQR)] | 16.00 (6.00, 42.00) | 18.00 (7.00, 42.00) | 16.00 (6.00, 42.00) | 0.033 |
| Sex, male (%) | 3,079 (80.9) | 917 (80.4) | 2,162 (81.2) | 0.602 |
| Race (%) | 0.822 | |||
| Asian | 274 (7.2) | 84 (7.4) | 190 (7.1) | |
| Black | 542 (14.2) | 163 (14.3) | 379 (14.2) | |
| Other | 50 (1.3) | 12 (1.1) | 38 (1.4) | |
| White | 2,939 (77.2) | 882 (77.3) | 2,057 (77.2) | |
| Primary site (%) | 0.44 | |||
| AF | 286 (7.5) | 80 (7.0) | 206 (7.7) | |
| Other | 1,444 (38.0) | 447 (39.2) | 997 (37.4) | |
| PS | 1,790 (47.0) | 538 (47.2) | 1,252 (47.0) | |
| PWH | 285 (7.5) | 76 (6.7) | 209 (7.8) | |
| Grade (%) | 0.36 | |||
| Grade I | 148 (3.9) | 48 (4.2) | 100 (3.8) | |
| Grade II | 1,498 (39.4) | 460 (40.3) | 1,038 (39.0) | |
| Grade III | 1,147 (30.1) | 355 (31.1) | 792 (29.7) | |
| Grade IV | 32 (0.8) | 9 (0.8) | 23 (0.9) | |
| Unknown | 980 (25.8) | 269 (23.6) | 711 (26.7) | |
| Behavior (%) | 0.866 | |||
| Other | 278 (7.3) | 84 (7.4) | 194 (7.3) | |
| SCC | 2,679 (70.4) | 795 (69.7) | 1,884 (70.7) | |
| SCC, keratinizing | 641 (16.8) | 201 (17.6) | 440 (16.5) | |
| SCC, non-keratinizing | 207 (5.4) | 61 (5.3) | 146 (5.5) | |
| Summary stage (%) | 0.236 | |||
| Distant | 1,329 (34.9) | 376 (33.0) | 953 (35.8) | |
| Localized | 667 (17.5) | 203 (17.8) | 464 (17.4) | |
| Regional | 1,809 (47.5) | 562 (49.3) | 1,247 (46.8) | |
| Stage group (%) | 0.229 | |||
| I | 143 (3.8) | 48 (4.2) | 95 (3.6) | |
| II | 330 (8.7) | 83 (7.3) | 247 (9.3) | |
| III | 548 (14.4) | 175 (15.3) | 373 (14.0) | |
| IV | 1,998 (52.5) | 596 (52.2) | 1,402 (52.6) | |
| Unknown | 786 (20.7) | 239 (20.9) | 547 (20.5) | |
| T* staging (%) | 0.122 | |||
| T0/T1 | 308 (8.1) | 100 (8.8) | 208 (7.8) | |
| T2 | 1,021 (26.8) | 283 (24.8) | 738 (27.7) | |
| T3 | 735 (19.3) | 242 (21.2) | 493 (18.5) | |
| T4 | 867 (22.8) | 249 (21.8) | 618 (23.2) | |
| TX | 257 (6.8) | 86 (7.5) | 171 (6.4) | |
| Unknown | 617 (16.2) | 181 (15.9) | 436 (16.4) | |
| N staging (%) | 0.963 | |||
| N0 | 988 (26.0) | 304 (26.6) | 684 (25.7) | |
| N1 | 566 (14.9) | 164 (14.4) | 402 (15.1) | |
| N2 | 1,430 (37.6) | 429 (37.6) | 1,001 (37.6) | |
| N3 | 156 (4.1) | 46 (4.0) | 110 (4.1) | |
| NX | 665 (17.5) | 198 (17.4) | 467 (17.5) | |
| Nodes, removed, yes (%) | 640 (16.8) | 206 (18.1) | 434 (16.3) | 0.199 |
| Surg rad seq (%) | 0.375 | |||
| 1 | 61 (1.6) | 23 (2.0) | 38 (1.4) | |
| 2 | 830 (21.8) | 242 (21.2) | 588 (22.1) | |
| 3 | 2,900 (76.2) | 870 (76.2) | 2,030 (76.2) | |
| Other | 14 (0.4) | 6 (0.5) | 8 (0.3) | |
| Surgery, yes (%) | 854 (22.4) | 268 (23.5) | 586 (22.0) | 0.333 |
| Radiation, yes (%) | 2,871 (75.5) | 863 (75.6) | 2,008 (75.4) | 0.897 |
| Chemotherapy, yes (%) | 2,311 (60.7) | 716 (62.8) | 1,595 (59.9) | 0.103 |
| Systemic, therapy, yes (%) | 775 (20.4) | 234 (20.5) | 541 (20.3) | 0.923 |
| Months, treatment (%) | 0.145 | |||
| <3 | 3,108 (81.7) | 952 (83.4) | 2,156 (80.9) | |
| >3 | 316 (8.3) | 90 (7.9) | 226 (8.5) | |
| Unknown | 381 (10.0) | 99 (8.7) | 282 (10.6) | |
| Nodes, positive, yes (%) | 2,686 (70.6) | 798 (69.9) | 1,888 (70.9) | 0.59 |
| Size (%) | 0.707 | |||
| <3 | 481 (12.6) | 147 (12.9) | 334 (12.5) | |
| >6 | 2,770 (72.8) | 836 (73.3) | 1,934 (72.6) | |
| 3–6 | 554 (14.6) | 158 (13.8) | 396 (14.9) | |
| Bone metastasis, yes (%) | 75 (2.0) | 19 (1.7) | 56 (2.1) | 0.447 |
| Liver metastasis (%) | 0.159 | |||
| No | 3,755 (98.7) | 1,129 (98.9) | 2,626 (98.6) | |
| Yes | 49 (1.3) | 11 (1.0) | 38 (1.4) | |
| Unknown | 1 (0.0) | 1 (0.1) | 0 (0.0) | |
| Lung metastasis (%) | 0.918 | |||
| No | 3,613 (95.0) | 1,085 (95.1) | 2,528 (94.9) | |
| Unknown | 12 (0.3) | 3 (0.3) | 9 (0.3) | |
| Yes | 180 (4.7) | 53 (4.6) | 127 (4.8) | |
| Node metastasis (%) | 0.933 | |||
| No | 1,161 (30.5) | 344 (30.1) | 817 (30.7) | |
| Unknown | 2,606 (68.5) | 785 (68.8) | 1,821 (68.4) | |
| Yes | 38 (1.0) | 12 (1.1) | 26 (1.0) | |
| Primary, yes (%) | 2,725 (71.6) | 809 (70.9) | 1,916 (71.9) | 0.549 |
| Number of malignant, >3 (%) | 127 (3.3) | 50 (4.4) | 77 (2.9) | 0.025 |
| Age, years (%) | 0.839 | |||
| <60 | 1,152 (30.3) | 353 (30.9) | 799 (30.0) | |
| >80 | 429 (11.3) | 130 (11.4) | 299 (11.2) | |
| 60–80 | 2,223 (58.4) | 658 (57.7) | 1,565 (58.7) | |
| Unknown | 1 (0.0) | 0 (0.0) | 1 (0.0) | |
| Marital status (%) | 0.752 | |||
| Divorced | 518 (13.6) | 142 (12.4) | 376 (14.1) | |
| Married | 1,710 (44.9) | 529 (46.4) | 1,181 (44.3) | |
| Other | 219 (5.8) | 63 (5.5) | 156 (5.9) | |
| Separated | 56 (1.5) | 16 (1.4) | 40 (1.5) | |
| Single | 915 (24.0) | 277 (24.3) | 638 (23.9) | |
| Widowed | 387 (10.2) | 114 (10.0) | 273 (10.2) | |
| Income (%) | 0.707 | |||
| <$40,000 | 252 (6.6) | 75 (6.6) | 177 (6.6) | |
| >$60,000 | 2,428 (63.8) | 739 (64.8) | 1,689 (63.4) | |
| $40,000–$60,000 | 1,125 (29.6) | 327 (28.7) | 798 (30.0) | |
*, TNM staging, TNM groups by 7th edition of the American Joint Committee on Cancer Classifications. AF, aryepiglottic fold; PS, pyriform sinus; PWH, posterior wall of hypopharynx; SCC, sequamous-cell carcinoma.