Table 1 Demographic and clinical characteristics
Before propensity score weighting | After propensity score weighting with rescaled IPTW* | |||||
|---|---|---|---|---|---|---|
Characteristic | Cetuximab±RT (N = 187) | Cisplatin±RT (N = 344) | P-valuea | Cetuximab±RT (N = 263) | Cisplatin±RT (N = 268) | P-valuea |
Age, years | <0.0001 | 0.902 | ||||
Mean (SD) | 63.9 (9.62) | 57.4 (8.58) | 59.3 (11.69) | 59.4 (7.70) | ||
Male, n (%) | 160 (85.6) | 281 (81.7) | 0.256 | 222 (84.4) | 219 (82.0) | 0.453 |
Race, n (%) | 0.075 | 0.298 | ||||
White | 154 (82.4) | 249 (72.4) | 208 (78.9) | 204 (76.1) | ||
Black or African American | 30 (16.0) | 83 (24.1) | 52 (19.9) | 54 (20.1) | ||
Other | 1 (0.5) | 5 (1.5) | 1 (0.4) | 4 (1.5) | ||
Undocumented | 2 (1.1) | 7 (2.0) | 2 (0.8) | 6 (2.3) | ||
Ethnicity, n (%) | 0.543 | 0.175 | ||||
Hispanic or Latino | 0 (0) | 2 (0.6) | 0 (0.0) | 2 (0.7) | ||
Not Hispanic or Latino | 187 (100.0) | 342 (99.4) | 263 (100.0) | 266 (99.3) | ||
BMI, kg/m2 | 0.857 | 0.773 | ||||
Mean (SD) | 26.7 (6.50) | 26.8 (6.27) | 27.0 (7.45) | 26.8 (5.41) | ||
Median | 25.7 | 26.0 | 26.6 | 26.0 | ||
Min., max. | 15.55, 59.41 | 13.62, 49.58 | 15.55, 59.41 | 13.62, 49.58 | ||
Type of insurance, n (%) | 0.054 | 0.877 | ||||
Private, no public | 48 (25.7) | 127 (36.9) | 84 (32.1) | 91 (33.8) | ||
Public, no private | 63 (33.7) | 102 (29.7) | 89 (33.9) | 83 (30.9) | ||
Public and private | 66 (35.3) | 98 (28.5) | 77 (29.1) | 80 (29.7) | ||
Other | 1 (0.5) | 6 (1.7) | 3 (1.0) | 5 (1.9) | ||
Unknown or undocumented | 9 (4.8) | 11 (3.2) | 10 (3.9) | 10 (3.6) | ||
US region of residence, n (%) | 0.005 | 0.627 | ||||
Northeast | 1 (0.5) | 2 (0.6) | 1 (0.5) | 1 (0.5) | ||
South | 147 (78.6) | 304 (88.4) | 227 (86.3) | 226 (84.3) | ||
Midwest | 39 (20.9) | 37 (10.8) | 35 (13.2) | 39 (14.6) | ||
West | 0 (0.0) | 1 (0.3) | 0 (0.0) | 2 (0.6) | ||
Stage of disease at initial diagnosis, n (%) | 0.228 | 0.388 | ||||
I | 3 (1.6) | 2 (0.6) | 5 (2.0) | 1 (0.5) | ||
II | 3 (1.6) | 4 (1.2) | 2 (0.9) | 5 (1.7) | ||
III | 55 (29.4) | 92 (26.7) | 74 (28.1) | 71 (26.6) | ||
IV | 10 (5.3) | 9 (2.6) | 13 (5.0) | 7 (2.5) | ||
IVA | 98 (52.4) | 202 (58.7) | 140 (53.0) | 154 (57.7) | ||
IVB | 9 (4.8) | 26 (7.6) | 18 (7.0) | 22 (8.4) | ||
Other | 1 (0.5) | 2 (0.6) | 1 (0.3) | 1 (0.5) | ||
Undocumented | 8 (4.3) | 7 (2.0) | 10 (3.8) | 6 (2.1) | ||
Tumor location at initial diagnosis, n (%) | ||||||
Oral cavity | 26 (13.9) | 38 (11.0) | 0.334 | 34 (12.8) | 32 (12.0) | 0.780 |
Pharynx | 119 (63.6) | 220 (64.0) | 0.942 | 170 (64.6) | 171 (63.9) | 0.868 |
Paranasal sinuses | 0 (0.0) | 2 (0.6) | 0.543 | 0 (0.0) | 3 (1.0) | 0.110 |
Salivary glands | 1 (0.5) | 4 (1.2) | 0.661 | 1 (0.3) | 3 (1.1) | 0.250 |
Larynx | 40 (21.4) | 81 (23.5) | 0.572 | 58 (22.0) | 60 (22.4) | 0.899 |
Unknown or undocumented | 3 (1.6) | 3 (0.9) | 0.430 | 4 (1.4) | 2 (0.8) | 0.494 |
HPV results, n (%) | 0.361 | 0.084 | ||||
Positive | 21 (70.0) | 24 (60.0) | 37 (82.9) | 16 (61.5) | ||
Negative | 7 (23.3) | 15 (37.5) | 6 (13.1) | 9 (35.8) | ||
Undocumented | 2 (6.7) | 1 (2.5) | 2 (3.9) | 1 (2.7) | ||
Tested for p16 status, n (%) | 0.0004 | 0.001 | ||||
No/undocumented | 144 (77.0) | 213 (61.9) | 200 (76.1) | 169 (63.2) | ||
Yes | 43 (23.0) | 131 (38.1) | 63 (23.9) | 98 (36.8) | ||
P16 results, n (%) | 0.817 | 0.104 | ||||
Positive | 30 (69.8) | 84 (64.1) | 53 (77.7) | 66 (62.4) | ||
Negative | 12 (27.9) | 44 (33.6) | 14 (20.7) | 38 (35.6) | ||
Undocumented | 1 (2.3) | 3 (2.3) | 1 (1.6) | 2 (2.1) | ||
Placement of feeding tube, n (%) | 0.398 | 0.967 | ||||
Not placed | 66 (35.3) | 109 (31.7) | 86 (32.5) | 88 (32.7) | ||
Placed | 121 (64.7) | 235 (68.3) | 178 (67.5) | 180 (67.3) | ||
Smoking status, n (%) | 0.073 | 0.318 | ||||
Current | 72 (38.5) | 155 (45.1) | 111 (42.3) | 120 (44.8) | ||
Past | 81 (43.3) | 123 (35.8) | 104 (39.6) | 97 (36.4) | ||
Never | 32 (17.1) | 66 (19.2) | 45 (17.1) | 50 (18.8) | ||
Unknown or undocumented | 2 (1.1) | 0 (0.0) | 3 (1.0) | 0 (0.0) | ||
Alcohol use, n (%) | 0.026 | 0.097 | ||||
Current abuse | 13 (7.0) | 35 (10.2) | 19 (7.2) | 24 (9.1) | ||
Current use | 67 (35.8) | 140 (40.7) | 99 (37.7) | 108 (40.5) | ||
No current use, no past use | 46 (24.6) | 87 (25.3) | 67 (25.5) | 66 (24.8) | ||
Past use, no current use | 31 (16.6) | 33 (9.6) | 45 (17.0) | 29 (11.0) | ||
Past abuse | 29 (15.5) | 38 (11.0) | 32 (12.1) | 31 (11.4) | ||
Unknown or undocumented | 1 (0.5) | 11 (3.2) | 1 (0.5) | 8 (3.2) | ||
ECOG PS, n (%) | 0.355 | 0.537 | ||||
0 | 45 (24.1) | 88 (25.6) | 74 (28.1) | 65 (24.4) | ||
1 | 34 (18.2) | 47 (13.7) | 40 (15.3) | 37 (13.8) | ||
2 | 7 (3.7) | 13 (3.8) | 6 (2.2) | 12 (4.4) | ||
3 | 2 (1.1) | 1 (0.3) | 2 (0.7) | 1 (0.3) | ||
4 | 1 (0.5) | 0 (0.0) | 1 (0.3) | 0 (0.0) | ||
Undocumented | 98 (52.4) | 195 (56.7) | 141 (53.5) | 153 (57.0) | ||
Composite performance status, n (%) | 0.346 | 0.663 | ||||
Impaired | 11 (5.9) | 14 (4.1) | 10 (4.0) | 13 (4.7) | ||
Not impaired | 176 (94.1) | 330 (95.9) | 253 (96.0) | 255 (95.3) | ||
Weighted index of comorbid conditions, n (%) | <0.0001 | 0.689 | ||||
0 | 84 (44.9) | 220 (64.0) | 161 (61.3) | 155 (57.8) | ||
1 | 62 (33.2) | 93 (27.0) | 67 (25.4) | 80 (30.0) | ||
2 | 23 (12.3) | 22 (6.4) | 21 (8.1) | 21 (7.9) | ||
3–5 | 17 (9.1) | 9 (2.6) | 13 (4.9) | 12 (4.4) | ||
6+ | 1 (0.5) | 0 (0.0) | 1 (0.3) | 0 (0.0) | ||