Table 1.
Patient characteristics
| Group (%) | All (181) | B7-H1 positivea N = 84 |
B7-H1 negative N = 97 |
p value |
|---|---|---|---|---|
| Age (mean ± SD) | 55.8 ± 9.4 n/a |
56.6 ± 10.0 | 55.1 ± 8.8 | 0.28 |
| Gender (%) | ||||
| Male | 186 (88.2) | 79 (94.0) | 83 (85.6) | 0.06 |
| Female | 23 (11.8) n/a |
5 (6.0) | 14 (14.4) | |
| Smoking (%) | ||||
| Yes (current/former) | 124 (68.5) | 54 (64.3) | 70 (72.2) | 0.26 |
| No (never) | 51 (28.2) | 27 (32.1) | 24 (24.7) | |
| Missing | 6 (3.3) | 3 (3.6) | 3 (3.1) | |
| T stage (%) | ||||
| T1/T2 | 105 (58.0) | 48 (57.1) | 57 (58.8) | 0.42 |
| T3/T4 | 66 (36.5) | 34 (40.5) | 32 (33.0) | |
| Missing | 10 (5.5) | 2 (2.4) | 8 (8.2) | |
| N stage (%) | ||||
| N0 | 16 (8.8) | 7 (8.3) | 9 (9.3) | 0.82 |
| N1–3 | 165 (91.2) | 77 (91.7) | 88 (90.7) | |
| AJCC stage | ||||
| I/II | 9 (5.0) | 2 (2.4) | 7 (7.2) | 0.12 |
| III/IV | 170 (94.0) | 82 (97.6) | 88 (90.7) | |
| Missing | 2 (1) | 2 (2.1) | ||
| Distant metastasis (%) | ||||
| Yes | 10 (5.5) | 7 (8.3) | 3 (3.1) | 0.10 |
| No | 171 (94.5) | 77 (91.7) | 94 (96.9) | |
| IMRT (%) | ||||
| Definitive | 38 (21.0) | 15 (17.9) | 23 (23.7) | 0.34 |
| Post-operative | 143 (79.0) | 69 (82.1) | 74 (76.3) | |
| Surgery only | 0 (0) | 0 (0) | 0 (0) | |
| Chemotherapy (%) | ||||
| Yes | 80 (44.2) | 29 (34.5) | 38 (39.2) | 0.10 |
| No | 74 (40.9) | 42 (50) | 45 (46.4) | |
| Unknown | 27 (14.9) | 13 (15.5) | 14 (14.4) | |
| Recurrence (%) | ||||
| Yes | 28 (15.5) | 12 (14.2) | 16 (16.5) | 0.66 |
| No | 152 (84.0) | 72 (85.8) | 80 (82.4) | |
| Missing | 1 (0.5) | 1 (1.9) | ||
| Histologic type (%) | ||||
| K SCC (type 1) | 37 (20.4) | 17 (20.2) | 22 (22.7) | 0.74 |
| NK SCC with | 45 (24.9) | 19 (22.6) | 24 (24.7) | |
| Maturation (type 2) | ||||
| NK SCC (type 3) | 98 (54.1) | 47 (56.0) | 51 (52.6) | |
| Missing | 1 (0.6) | 1 (1.2) | 0 | |
| p16 Status (%)b | ||||
| Positive | 134 (79.3) | 61 (72.6) | 73 (75.2) | 0.78 |
| Negative | 35 (19.3) | 15 (17.8) | 20 (20.6) | |
| Missing | 12 (1.4) | 8 (9.6) | 4 (4.2) | |
IMRT intensity modulated radiation therapy, K SCC keratinizing type squamous cell carcinoma, NK SCC nonkeratinizing squamous cell carcinoma
aB7-H1 expression considered binarily as positive (>5 % staining) versus negative (no staining or less than 5 % staining)
bp16 immunohistochemistry status considered binarily as positive ≥50 % tumor cell staining and negative = no staining or <50 % tumor cell staining