Table 1.
Characteristics of Lung Cancer Patients and Controls From the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial
| Characteristic | With Available Serum |
With Available DNA |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Controls (n = 670) |
Patients (n = 592) |
P* | Controls (n = 447) |
Patients (n = 378) |
P* | |||||
| No. | % | No. | % | No. | % | No. | % | |||
| Age at enrollment, years | —† | —† | ||||||||
| ≤ 59 | 120 | 17.9 | 112 | 18.9 | 88 | 19.7 | 80 | 21.2 | ||
| 60-64 | 188 | 28.1 | 164 | 27.7 | 129 | 28.8 | 106 | 28.0 | ||
| 65-69 | 215 | 32.1 | 197 | 33.3 | 147 | 32.9 | 128 | 33.9 | ||
| 70-74 | 147 | 21.9 | 119 | 20.1 | 83 | 18.6 | 64 | 16.9 | ||
| Sex | —† | —† | ||||||||
| Female | 234 | 34.9 | 186 | 31.4 | 177 | 39.6 | 131 | 34.7 | ||
| Male | 436 | 65.1 | 406 | 68.6 | 270 | 60.4 | 247 | 65.3 | ||
| Smoking status | —† | —† | ||||||||
| Never smoker | 117 | 17.5 | 39 | 6.6 | 98 | 21.9 | 30 | 7.9 | ||
| Former smoker | 317 | 47.3 | 317 | 53.5 | 217 | 48.6 | 217 | 57.4 | ||
| 0-29 Pack-years and quit for < 15 years | 30 | 4.5 | 30 | 5.1 | 21 | 4.7 | 23 | 6.1 | ||
| 0-29 Pack-years and quit for ≥ 15 years | 65 | 9.7 | 65 | 11.0 | 49 | 11.0 | 44 | 11.6 | ||
| 30-39 Pack-years and quit for < 15 years | 48 | 7.2 | 48 | 8.1 | 32 | 7.1 | 30 | 7.9 | ||
| 30-39 Pack-years and quit for ≥ 15 years | 21 | 3.1 | 21 | 3.5 | 16 | 3.6 | 17 | 4.5 | ||
| 40-49 Pack-years and quit for < 15 years | 18 | 2.7 | 18 | 3.0 | 15 | 3.3 | 14 | 3.7 | ||
| 40-49 Pack-years and quit for ≥ 15 years | 13 | 1.9 | 13 | 2.2 | 8 | 1.8 | 11 | 2.9 | ||
| 50+ Pack-years and quit for < 15 years | 103 | 15.4 | 103 | 17.4 | 64 | 14.3 | 66 | 17.5 | ||
| 50+ Pack-years and quit for ≥ 15 years | 19 | 2.8 | 19 | 3.2 | 12 | 2.7 | 12 | 3.2 | ||
| Current smoker | 236 | 35.2 | 236 | 39.9 | 132 | 29.4 | 131 | 34.7 | ||
| 0-29 Pack-years | 49 | 7.3 | 49 | 8.3 | 32 | 7.1 | 26 | 6.9 | ||
| 30-39 Pack-years | 73 | 10.9 | 73 | 12.3 | 40 | 8.9 | 39 | 10.3 | ||
| 40-49 Pack-years | 18 | 2.7 | 18 | 3.1 | 9 | 2.0 | 11 | 2.9 | ||
| 50+ Pack-years | 96 | 14.3 | 96 | 16.2 | 51 | 11.4 | 55 | 14.6 | ||
| Race/ethnicity | .114 | .386 | ||||||||
| White | 610 | 91.0 | 522 | 88.2 | 407 | 91.0 | 338 | 89.4 | ||
| Black | 29 | 4.3 | 43 | 7.3 | 20 | 4.5 | 27 | 7.1 | ||
| Hispanic | 6 | 0.9 | 10 | 1.7 | 7 | 1.6 | 4 | 1.1 | ||
| Asian/Pacific Islander | 25 | 3.7 | 17 | 2.9 | 13 | 2.9 | 9 | 2.4 | ||
| Education | .017 | .172 | ||||||||
| High school graduate or less | 216 | 32.2 | 233 | 39.4 | 155 | 34.7 | 148 | 39.2 | ||
| College or more | 454 | 67.8 | 359 | 60.6 | 292 | 65.3 | 230 | 60.8 | ||
| Body mass index at enrollment | .143 | .255 | ||||||||
| < 18.5 | 4 | 0.6 | 8 | 1.4 | 2 | 0.4 | 4 | 1.0 | ||
| 18.5-24.9 | 216 | 32.2 | 217 | 36.7 | 140 | 31.3 | 121 | 32.0 | ||
| 25.0-29.9 | 313 | 46.7 | 253 | 42.7 | 211 | 47.2 | 162 | 42.9 | ||
| ≥ 30 | 126 | 18.8 | 109 | 18.4 | 88 | 19.7 | 88 | 23.3 | ||
| Missing | 11 | 1.7 | 5 | 0.8 | 6 | 1.3 | 3 | 0.8 | ||
| Regular use of aspirin or ibuprofen | .584 | .248 | ||||||||
| Yes | 437 | 65.2 | 381 | 64.4 | 300 | 67.1 | 242 | 64.0 | ||
| No | 233 | 34.8 | 210 | 35.5 | 147 | 32.9 | 136 | 36.0 | ||
| Missing | 0 | 0.0 | 1 | 0.1 | 0 | 0.0 | 0 | 0.0 | ||
| History of bronchitis/emphysema | < .001 | .073 | ||||||||
| Yes | 72 | 10.8 | 111 | 18.8 | 47 | 10.5 | 62 | 16.4 | ||
| No | 586 | 87.4 | 458 | 77.3 | 392 | 87.7 | 300 | 79.4 | ||
| Missing | 12 | 1.8 | 23 | 3.9 | 8 | 1.8 | 16 | 4.2 | ||
| History of heart disease | .804 | .329 | ||||||||
| Yes | 96 | 14.3 | 93 | 15.7 | 55 | 12.3 | 62 | 16.4 | ||
| No | 561 | 83.7 | 470 | 79.4 | 383 | 85.7 | 300 | 79.4 | ||
| Missing | 13 | 2.0 | 29 | 4.9 | 9 | 2.0 | 16 | 4.2 | ||
| Family history of lung cancer | .004 | .012 | ||||||||
| Yes | 74 | 11.0 | 103 | 17.4 | 49 | 11.0 | 67 | 17.7 | ||
| No | 568 | 84.8 | 451 | 76.2 | 384 | 85.9 | 288 | 76.2 | ||
| Missing | 28 | 4.2 | 38 | 6.4 | 14 | 3.1 | 23 | 6.1 | ||
NOTE. Of the 626 patients and 716 controls included in this study, serum specimens were available for 592 patients and 670 controls, and DNA specimens were available for 378 patients and 447 controls. Results are shown separately for subjects with available serum or DNA specimens. P values in boldface are statistically significant at P < .05.
P values are from conditional logistic regression models. Models included adjustment for study matching factors: age at enrollment, sex, year of random assignment, follow-up time in study in years, and smoking status (never smokers, former smokers matched on pack-years of smoking and time since quitting, and current smokers matched on pack-years of smoking). Subjects with missing values were excluded from the P value calculation.
Matching variable. The distributions do not appear identical in the table because the case:control ratio varies according to smoking status.