Table 1.
Demographics of pretreatment features (before decision 1 [D1]: induction chemotherapy or not; N=536).
| Characteristics | All patients (N=536) | Training set (n=402) | Testing set (n=134) | |||||
| Group 1: Pretreatment features (before D1) | ||||||||
|
|
Age (years) at diagnosis, mean (SD) | 58.9 (9.5) | 58.5 (9.4) | 60.2 (9.6) | ||||
|
|
Pathological grade, n (%) | |||||||
|
|
|
I | 6 (1.1) | 2 (0.5) | 4 (3) | |||
|
|
|
II | 154 (28.7) | 114 (28.4) | 40 (29.9) | |||
|
|
|
III | 274 (51.1) | 206 (51.2) | 88 (65.7) | |||
|
|
|
IV | 3 (0.6) | 1 (0.2) | 2 (1.5) | |||
|
|
|
Not available | 99 (18.5) | 79 (19.7) | 20 (14.9) | |||
|
|
Sex (male), n (%) | 471 (87.9) | 355 (88.3) | 116 (86.6) | ||||
|
|
HPVa or P16b status, n (%) | |||||||
|
|
|
Negative | 43 (8) | 33 (8.2) | 10 (7.5) | |||
|
|
|
Positive | 305 (56.9) | 228 (56.7) | 77 (57.5) | |||
|
|
|
Unknown | 188 (35.1) | 141 (35.1) | 47 (35.1) | |||
|
|
Tc category, n (%) | |||||||
|
|
|
T1 | 113 (21.1) | 87 (21.6) | 26 (19.4) | |||
|
|
|
T2 | 219 (40.9) | 156 (38.8) | 63 (47) | |||
|
|
|
T3 | 116 (21.6) | 91 (22.6) | 25 (18.7) | |||
|
|
|
T4 | 86 (16) | 67 (16.7) | 19 (14.2) | |||
|
|
|
Txd | 2 (0.4) | 1 (0.2) | 1 (0.7) | |||
|
|
Ne category (8th editionf), n (%) | |||||||
|
|
|
N0g | 20 (3.7) | 14 (3.5) | 6 (4.5) | |||
|
|
|
N1 | 249 (46.5) | 181 (45) | 68 (50.7) | |||
|
|
|
N2 | 250 (46.6) | 194 (48.3) | 56 (41.8) | |||
|
|
|
N3 | 17 (3.2) | 13 (3.2) | 4 (3) | |||
|
|
AJCCh (8th edition), n (%) | |||||||
|
|
|
I | 186 (34.7) | 137 (34.1) | 49 (36.6) | |||
|
|
|
II | 81 (15.1) | 63 (15.7) | 18 (13.4) | |||
|
|
|
III | 64 (11.9) | 44 (10.9) | 20 (14.9) | |||
|
|
|
IV | 203 (37.9) | 157 (39.1) | 46 (34.3) | |||
|
|
|
Not available | 2 (0.3) | 1 (0.2) | 1 (0.7) | |||
|
|
Smoking status at diagnosis, n (%) | |||||||
|
|
|
Current | 115 (21.5) | 85 (21.1) | 30 (22.4) | |||
|
|
|
Former | 203 (37.9) | 151 (37.6) | 52 (38.8) | |||
|
|
|
Never | 218 (40.7) | 166 (41.3) | 52 (38.8) | |||
|
|
Smoking status | |||||||
|
|
|
Packs per year, mean (SD) | 17.7 (23.7) | 16.7 (22.9) | 20.5 (26) | |||
|
|
|
Not available, n (%) | 28 (4.7) | 21 (5.2) | 7 (5.2) | |||
|
|
Aspiration rate before therapy (no), n (%) | 16 (3) | 14 (3.5) | 2 (1.5) | ||||
|
|
Number of affected lymph nodes, mean (SD) | 2.0 (1.3) | 2.1 (1.3) | 1.8 (1) | ||||
|
|
Tumor laterality, n (%) | |||||||
|
|
|
Bilateral | 21 (3.9) | 16 (4) | 5 (3.7) | |||
|
|
|
Left | 242 (45.1) | 188 (46.8) | 54 (40.3) | |||
|
|
|
Right | 273 (50.9) | 198 (49.3) | 75 (56) | |||
|
|
Tumor subsite, n (%) | |||||||
|
|
|
Base of tongue | 266 (49.6) | 204 (50.7) | 62 (46.3) | |||
|
|
|
Tonsil | 223 (41.6) | 158 (39.3) | 65 (48.5) | |||
|
|
|
Other | 47 (8.8) | 40 (10) | 7 (5.2) | |||
|
|
Race, n (%) | |||||||
|
|
|
African American or Black | 16 (3) | 10 (2.5) | 6 (4.5) | |||
|
|
|
Asian | 4 (0.7) | 3 (0.7) | 1 (0.7) | |||
|
|
|
Hispanic or Latino | 21 (3.9) | 17 (4.2) | 4 (3) | |||
|
|
|
Native American | 1 (0.2) | 1 (0.2) | 0 (0) | |||
|
|
|
White or other | 494 (92.2) | 371 (92.3) | 123 (91.8) | |||
aHPV: human papillomavirus.
bP16: protein expression 16.
cT: primary tumor.
dTx: no information about the primary tumor or it cannot be measured.
eN: lymph nodes.
fAmerican Joint Committee on Cancer’s Cancer Staging Manual, 8th edition.
gN0: nearby lymph nodes do not contain cancer.
hAJCC: American Joint Committee on Cancer.