Table 1.
Baseline characteristics of patients with lung cancer in the original/matched data sets (N=15 696).
| Characteristics | Original data set | Matched data set | ||||
| No prior cancer N=87 674 (%) |
With prior cancer N=15 696 (%) |
P value | No prior cancer N=15 696 (%) |
With prior cancer N=15 696 (%) |
P value | |
| Age (years), mean (SD) | 56.86 (6.64) | 58.55 (5.91) | <0.001 | 58.74 (5.64) | 58.55 (5.91) | 0.005 |
| Race (%) | <0.001 | 0.301 | ||||
| Black | 13 230 (15.1) | 2003 (12.8) | 1937 (12.3) | 2003 (12.8) | ||
| Unknown/others | 5552 (6.3) | 649 (4.1) | 615 (3.9) | 649 (4.1) | ||
| White | 68 892 (78.6) | 13 044 (83.1) | 13 144 (83.7) | 13 044 (83.1) | ||
| Gender | <0.001 | 0.892 | ||||
| Male | 49 396 (56.3) | 7242 (46.1) | 7255 (46.2) | 7242 (46.1) | ||
| Female | 38 278 (43.7) | 8454 (53.9) | 8441 (53.8) | 8454 (53.9) | ||
| Marital status | <0.001 | 0.699 | ||||
| Unmarried | 41 228 (47.0) | 6962 (44.4) | 6997 (44.6) | 6962 (44.4) | ||
| Married | 46 446 (53.0) | 8734 (55.6) | 8699 (55.4) | 8734 (55.6) | ||
| Primary site | <0.001 | 0.532 | ||||
| Main bronchus | 5534 (6.3) | 733 (4.7) | 734 (4.7) | 733 (4.7) | ||
| Upper lobe | 44 914 (51.2) | 8097 (51.6) | 8240 (52.5) | 8097 (51.6) | ||
| Middle lobe | 3535 (4.0) | 732 (4.7) | 686 (4.4) | 732 (4.7) | ||
| Lower lobe | 18 213 (20.8) | 3777 (24.1) | 3705 (23.6) | 3777 (24.1) | ||
| Overlapping lesion | 1274 (1.5) | 179 (1.1) | 164 (1.0) | 179 (1.1) | ||
| Lung, NOS | 14 204 (16.2) | 2178 (13.9) | 2167 (13.8) | 2178 (13.9) | ||
| AJCC group | <0.001 | 0.020 | ||||
| I | 12 420 (14.2) | 4290 (27.3) | 4152 (26.5) | 4290 (27.3) | ||
| II | 3728 (4.3) | 777 (5.0) | 805 (5.1) | 777 (5.0) | ||
| III | 21 389 (24.4) | 3596 (22.9) | 3714 (23.7) | 3596 (22.9) | ||
| IV | 44 175 (50.4) | 5649 (36.0) | 5765 (36.7) | 5649 (36.0) | ||
| Unknown | 5962 (6.8) | 1384 (8.8) | 1260 (8.0) | 1384 (8.8) | ||
| Surgery | <0.001 | 0.934 | ||||
| Yes | 19 232 (21.9) | 5457 (34.8) | 5465 (34.8) | 5457 (34.8) | ||
| No/unknown | 68 442 (78.1) | 10 239 (65.2) | 10 231 (65.2) | 10 239 (65.2) | ||
| Radiotherapy | <0.001 | 0.850 | ||||
| Yes | 39 779 (45.4) | 5525 (35.2) | 5508 (35.1) | 5525 (35.2) | ||
| No/unknown | 47 895 (54.6) | 10 171 (64.8) | 10 188 (64.9) | 10 171 (64.8) | ||
| Grade | <0.001 | 0.667 | ||||
| Well differentiated | 3069 (3.5) | 950 (6.1) | 897 (5.7) | 950 (6.1) | ||
| Moderately differentiated | 11 510 (13.1) | 2864 (18.2) | 2820 (18.0) | 2864 (18.2) | ||
| Poorly differentiated | 22 875 (26.1) | 4131 (26.3) | 4190 (26.7) | 4131 (26.3) | ||
| Undifferentiated | 5055 (5.8) | 680 (4.3) | 682 (4.3) | 680 (4.3) | ||
| Unknown | 45 165 (51.5) | 7071 (45.0) | 7107 (45.3) | 7071 (45.0) | ||
| Stage | <0.001 | 0.033 | ||||
| Distant | 53 977 (61.6) | 7078 (45.1) | 7162 (45.6) | 7078 (45.1) | ||
| Localised | 10 937 (12.5) | 3976 (25.3) | 3822 (24.4) | 3976 (25.3) | ||
| Regional | 19 995 (22.8) | 4011 (25.6) | 4142 (26.4) | 4011 (25.6) | ||
| Unknown/unstaged | 2765 (3.2) | 631 (4.0) | 570 (3.6) | 631 (4.0) | ||
AJCC, American Joint Committee on Cancer; NOS, not otherwise specified.