Table 1.
All patients with surgery for IPLC in the SEER from 1998 to 2013, stratified by SPLC vs single primary lung cancer
| Characteristics | Total (n = 138 969) | Patients with SPLC (n = 12 115) | Patients with single primary lung cancer (n = 126 854) |
|---|---|---|---|
| Age at IPLC diagnosis | |||
| Mean (SD) | 67.1 (10.6) | 66.8 (8.9) | 67.2 (10.7) |
| Age at IPLC diagnosis in groups, No. (%) | |||
| 0-49 y | 7986 (5.7) | 447 (3.7) | 7539 (5.9) |
| 50-59 y | 22 608 (16.3) | 1962 (16.2) | 20 646 (16.3) |
| 60-69 y | 45 396 (32.7) | 4804 (39.7) | 40 592 (32.0) |
| 70-79 y | 48 391 (34.8) | 4109 (33.9) | 44 282 (34.7) |
| ≥80 y | 14 588 (10.5) | 793 (6.5) | 13 795 (10.9) |
| Sex, No. (%) | |||
| Male | 69 017 (49.7) | 5571 (46.0) | 63 446 (50.1) |
| Female | 69 952 (50.3) | 6544 (54.0) | 63 408 (49.9) |
| Race, No. (%) | |||
| African American | 11 520 (8.3) | 962 (7.9) | 10 558 (8.3) |
| Asian and Pacific Islander | 7287 (5.2) | 518 (4.3) | 6769 (5.3) |
| Hispanic | 6201 (4.5) | 422 (3.5) | 5779 (4.6) |
| Other | 521 (0.4) | 31 (0.3) | 490 (0.4) |
| White | 113 440 (81.6) | 10 182 (84.0) | 103 258 (81.4) |
| Personal history of cancer, No. (%) | |||
| Yes | 28 364 (20.4) | 2480 (20.5) | 25 884 (20.4) |
| No | 110 605 (79.6) | 9635 (79.5) | 100 970 (79.6) |
| Stage at IPLCa, No. (%) | |||
| Early | 133 445 (96.0) | 11 861 (97.9) | 121 584 (95.8) |
| Advanced | 5524 (4.0) | 254 (2.1) | 5270 (4.2) |
| Histology of IPLC, No. (%) | |||
| Adenocarcinoma | 75 738 (54.5) | 6631 (54.7) | 69 107 (54.5) |
| Large cell | 4911 (3.5) | 467 (3.9) | 4444 (3.5) |
| Squamous cell | 35 666 (25.7) | 3488 (28.8) | 32 178 (25.4) |
| Small cell | 1970 (1.4) | 133 (1.1) | 1837 (1.4) |
| Non-small cell carcinoma/NOS | 5721 (4.1) | 535 (4.4) | 5186 (4.1) |
| Others | 14 963 (10.8) | 861 (7.1) | 14 102 (11.1) |
| Radiotherapy for IPLC, No. (%) | |||
| Yes | 20 269 (14.6) | 1216 (10.0) | 19053 (15.0) |
| No | 117 868 (84.8) | 10 851 (89.6) | 107 017 (84.4) |
| Missing | 832 (0.6) | 48 (0.4) | 784 (0.6) |
| Chemotherapy for IPLC, No. (%) | |||
| Yes | 31 268 (22.5) | 2322 (19.2) | 28 946 (22.8) |
| No/Unknown | 107 701 (77.5) | 9793 (80.8) | 97 908(77.2) |
| Follow-up status/cause of death, No. (%) | |||
| Alive | 48 202 (34.7) | 3936 (32.5) | 44 266 (34.9) |
| Dead/Lung cancer | 53 916 (38.8) | 6033 (49.8) | 47 883 (37.7) |
| Dead/Other causes | 36 851 (26.5) | 2146 (17.7) | 34 705 (27.4) |
a
Stage of IPLC was defined using SEER summary stage: “localized” and “regional” for early stage and “distant” for advanced stage. IPLC = initial primary lung cancer; NOS = not otherwise specified; SEER = Surveillance, Epidemiology, and End Results Program; SPLC = second primary lung cancer.