Table 1.
Characteristics of 8,031 patients aged 55–80 years in the hospital and community cohort with long-term quitters, diagnosed 1997–2015
| Hospital Cohort (n=7168) | Community Cohort (n=863) | |||||||
|---|---|---|---|---|---|---|---|---|
| Characteristics | Long-term quitters* | USPSTF criteria† | Total | P value | Long-term quitters* | USPSTF criteria† | Total | P value |
| (N=1299) | (N=5869) | (N=7168) | (N=105) | (N=758) | (N=863) | |||
| Age at diagnosis, mean (SD), year | 71·7 (5·7) | 66·7 (6·5) | 67·6 (6·6) | <0·0001 | 72·7 (5·6) | 67·8 (6·7) | 68·4 (6·8) | <0 0001 |
| Sex, No- (%) | ||||||||
| Female | 394 (30·3%) | 2477 (42·2%) | 2871 (40·1%) | <0· 0001 | 27 (25·7%) | 317 (41·8%) | 344 (39·9%) | 0·002 |
| Male | 905 (69·7%) | 3392 (57·8%) | 4297 (59·9%) | 78 (74·3%) | 441 (58·2%) | 519 (60·1%) | ||
| Race/ethnicity, No. (%) | ||||||||
| Caucasian | 1192 (91·8%) | 5210 (88·8%) | 6402 (89·3%) | 0·002 | 103 (98·1%) | 731 (96·4%) | 834 (96·6%) | 0·38 |
| Others | 107 (8·2%) | 659 (11·2%) | 766 (10·7%) | 2 (1·9%) | 27 (3·6%) | 29 (3·4%) | ||
| Cigarette smoking status at diagnosis, No. (%) | ||||||||
| Former | 1299 (100·0%) | 2262 (38·5%) | 3561 (49·7%) | NA | 105 (100·0%) | 296 (39·1%) | 401 (46·5%) | NA |
| Current | NA | 3607 (61·5%) | 3607 (50·3%) | NA | 462 (60·9%) | 462 (53·5%) | ||
| Pack-years, median (IQR)‡ | 47 (36·0, 65·0) | 56 (44·0, 80·0) | 54 (41·0, 78·0) | <0·0001 | 52 (40·0, 75·0) | 60 (46·0, 80·0) | 60 (45·0, 80·0) | 0·004 |
| Tumor stage, No. (%)§ | ||||||||
| NSCLC, No. (%) | 1143 (88·0%) | 4864 (82·9%) | 6007 (83·8%) | 95 (90·5%) | 625 (82·5%) | 720 (83·4%) | ||
| I | 357 (31·2%) | 1300 (26·7%) | 1657 (27·6%) | 32 (33·7%) | 199 (31·8%) | 231 (32·1%) | ||
| II | 139 (12·2%) | 538 (11·1%) | 677 (11·3%) | 0·001 | 9 (95%) | 48 (7·7%) | 57 (7·9%) | 0·89 |
| III | 271 (23·7%) | 1388 (28·5%) | 1659 (27·6%) | 25 (26·3%) | 170 (27·2%) | 195 (27·1%) | ||
| IV | 376 (32·9%) | 1638 (33·7%) | 2014 (33·5%) | 29 (30·5%) | 208 (33·3%) | 237 (32·9%) | ||
| SCLC, No. (%) | 126 (9·7%) | 901 (15·4%) | 1027 (14·3%) | 10 (9·5%) | 133 (17·5%) | 143 (16·6%) | ||
| Limited | 53 (42·1%) | 399 (44·3%) | 452 (44·0%) | 0·64 | 3 (30·0%) | 51 (38·3%) | 54 (37·8%) | 0·60 |
| Extensive | 73 (57·9%) | 502 (55·7%) | 575 (56·0%) | 7 (70·0%) | 82 (61·7%) | 89 (62·2%) | ||
| Histology, No. (%) | ||||||||
| Adenocarcinoma | 647 (49·8%) | 2367 (40·3%) | 3014 (42·0%) | 57 (54·3%) | 266 (35·1%) | 323 (37·4%) | ||
| Squamous cell carcinoma | 341 (26·3%) | 1612 (27·5%) | 1953 (27·2%) | 27 (25·7%) | 239 (31·5%) | 266 (30·8%) | ||
| Small cell carcinoma | 128 (9·9%) | 915 (15·6%) | 1043 (14·6%) | <0·0001 | 10 (9·5%) | 135 (17·8%) | 145 (16·8%) | 0·003 |
| Other NSCLC|| | 34 (2·6%) | 178 (3·0%) | 212 (3·0%) | 3 (2·9%) | 48 (6·3%) | 51 (5·9%) | ||
| Unspecified NSCLC | 149 (11·5%) | 797 (13·6%) | 946 (13·2%) | 8 (7·6%) | 70 (9·2%) | 78 (9%) | ||
| Treatment, No. (%)¶ | ||||||||
| Surgery only | 389 (29·9%) | 1359 (23·2%) | 1748 (24·4%) | 34 (32·4%) | 193 (25·5%) | 227 (26·3%) | ||
| Chemotherapy only | 216 (166%) | 975 (16·6%) | 1191 (166%) | <0·0001 | 18 (171%) | 116 (153%) | 134 (155%) | 0·60 |
| Chemotherapy & Radiation | 189 (14·5%) | 1150 (19·6%) | 1339 (18·7%) | 17 (16·2%) | 170 (22·4%) | 187 (21·7%) | ||
| Radiation only | 94 (7·2%) | 385 (6·6%) | 479 (6·7%) | 13 (12·4%) | 80 (10·6%) | 93 (10·8%) | ||
| Surgery & Chemotherapy | 83 (6·4%) | 300 (5·1%) | 383 (5·3%) | 2 (1·9%) | 28 (3·7%) | 30 (3·5%) | ||
| Surgery & Radiation | 28 (2·2%) | 128 (2·2%) | 156 (2·2%) | 4 (3·8%) | 21 (2·8%) | 25 (2·9%) | ||
| Surgery & Chemotherapy & Radiation | 59 (4·5%) | 355 (6·0%) | 414 (5·8%) | 3 (2·9%) | 31 (4·1%) | 34 (3·9%) | ||
| Other treatment | 39 (3·0%) | 230 (3·9%) | 269 (3·8%) | 4 (3·8%) | 22 (2·9%) | 26 (3·0%) | ||
| No treatment | 145 (11·2%) | 741 (12·6%) | 886 (12·4%) | 10 (9·5%) | 97 (12·8%) | 107 (12·4%) | ||
Abbreviations: USPSTF, the U.S. Preventive Services Task Force; SD, standard deviation; IQR, interquartile range; NA, not applicable; NSCLC, non-small cell lung cancer; SCLC, small cell lung cancer.
Long-term quitters: individual aged 55 to 80, who have a smoking history of 30 or more pack-years and had quitted smoking for 15–30 years.
USPSTF criteria: individual aged 55 to 80, who have a current or past smoking history of 30 or more pack-years, if former smokers, who had quitted within the past 15 years.
Pack-years: pack smoked daily × years.
Unknown stage: 30 (2·3%) of the 1299 long-term quitters and 104 (1·8%) of 5869 patients among the USPSTF group in the hospital cohort.
Large neuroendocrine and adenosquamous carcinoma.
Unknown treatment: 57 (4·4%) of 1299 long-term quitters and 246 (4·2%) of 5869 patients among the USPSTF group in the hospital cohort.