Table 2. Basic characteristics of surgically resected, primary M0 stages invasive mucinous and nonmucinous adenocarcinoma.
| Variables | Before matching | After matching | |||||
|---|---|---|---|---|---|---|---|
| IMA (N=531) | NMA (N=34,875) | P value | IMA (N=531) | NMA (N=1,593) | P value | ||
| Age (years) | 65.64±11.34 | 66.23±10.24 | 0.239 | 65.34±11.34 | 65.64±10.56 | 0.213 | |
| Female sex | 326 (61.4%) | 19,849 (56.9%) | 0.043 | 205 (38.6%) | 674 (42.3%) | 0.147 | |
| Race | 0.360 | 0.616 | |||||
| Black | 54 (10.2%) | 2,963 (8.5%) | 54 (10.2%) | 141 (8.9%) | |||
| White | 434 (81.7%) | 28,879 (82.8%) | 434 (81.7%) | 1,327 (83.3%) | |||
| Others | 43 (8.1%) | 3,033 (8.7%) | 43 (8.1%) | 125 (7.8%) | |||
| Marriage | 0.028 | 0.035 | |||||
| Married/partner | 335 (63.1%) | 20,493 (58.8%) | 335 (63.1%) | 919 (57.7%) | |||
| Separated | 119 (22.4%) | 9,483 (27.2%) | 119 (22.4%) | 445 (27.9%) | |||
| Single | 51 (9.6%) | 3,659 (10.5%) | 51 (9.6%) | 171 (10.7%) | |||
| Unknown | 26 (4.9%) | 1,240 (3.6%) | 26 (4.9%) | 58 (3.6%) | |||
| Insurance | 0.082 | 0.135 | |||||
| Insured | 259 (48.8%) | 18,250 (52.3%) | 259 (48.8%) | 802 (50.3%) | |||
| Medicaid | 22 (4.1%) | 1,971 (5.7%) | 22 (4.1%) | 84 (5.3%) | |||
| Uninsured | 6 (1.1%) | 409 (1.2%) | 6 (1.1%) | 6 (0.4%) | |||
| Unknown | 244 (46.0%) | 14,245 (40.8%) | 244 (46.0%) | 701 (44.0%) | |||
| Grade | <0.001 | <0.001 | |||||
| Grade I | 304 (57.3%) | 6,063 (17.4%) | 304 (57.3%) | 288 (18.1%) | |||
| Grade II | 84 (15.8%) | 15,430 (44.2%) | 84 (15.8%) | 703 (44.1%) | |||
| Grade III | 14 (2.6%) | 11,060 (31.7%) | 14 (2.6%) | 500 (31.4%) | |||
| Grade IV | 0 (0.0%) | 257 (0.7%) | 0 (0.0%) | 18 (1.1%) | |||
| Unknown | 129 (24.3%) | 2065 (5.9%) | 129 (24.3%) | 84 (5.3%) | |||
| Laterality | 0.420 | 0.722 | |||||
| Left | 222 (41.8%) | 13,859 (39.7%) | 222 (41.8%) | 650 (40.8%) | |||
| Right | 309 (58.2%) | 21,008 (60.2%) | 309 (58.2%) | 943 (59.2%) | |||
| One side | 0 (0.0%) | 8 (0.0%) | – | – | |||
| Location | <0.001 | <0.001 | |||||
| Upper | 163 (30.7%) | 21,472 (62.3%) | 163 (30.7%) | 974 (61.1%) | |||
| Middle | 29 (5.5%) | 1,787 (5.1%) | 29 (5.5%) | 83 (5.2%) | |||
| Lower | 319 (60.1%) | 10,327 (29.6%) | 319 (60.1%) | 486 (30.5%) | |||
| Other | 20 (3.8%) | 1,019 (2.9%) | 20 (3.8%) | 50 (3.1%) | |||
| SPN* | 17 (4.0%) | 1,174 (4.3%) | 0.811 | 17 (4.0%) | 48 (3.7%) | 0.907 | |
| Pleura involvement† | N=138 | N=13,490 | <0.001 | N=138 | N=423 | <0.001 | |
| Yes | 13 (9.4%) | 3,192 (23.7%) | 13 (9.4%) | 116 (27.4%) | |||
| No | 112 (81.2%) | 8,810 (65.3%) | 112 (81.2%) | 262 (61.9%) | |||
| Unknown | 13 (9.4%) | 1,488 (11.0%) | 13 (9.4%) | 45 (10.6%) | |||
| Tumor diameter (mm) | 40.14±34.44 | 29.63±18.84 | <0.001 | 40.14±34.44 | 30.54±17.91 | <0.001 | |
| Number of LNs positive | 0.16±0.74 | 0.75±2.04 | <0.001 | 0.16±0.74 | 0.22±1.03 | 0.779 | |
| Number of LNs resected | 8.48±7.55 | 9.26±7.60 | 0.027 | 8.48±7.55 | 8.76±7.37 | 0.488 | |
| T stage [2000–2003] | N=102 | N=7,686 | <0.001 | N=102 | N=290 | 0.066 | |
| T1 | 26 (25.5%) | 3,149 (41.0%) | 26 (25.5%) | 75 (25.9%) | |||
| T2 | 66 (64.7%) | 3,408 (44.3%) | 66 (64.7%) | 175 (60.3%) | |||
| T3 | 1 (1.0%) | 382 (5.0%) | 1 (1.0%) | 23 (7.9%) | |||
| T4 | 9 (8.8%) | 747 (9.7%) | 9 (8.8%) | 17 (5.9%) | |||
| T stage [2004–2009] | N=291 | N=13,699 | <0.001 | N=291 | N=880 | 0.028 | |
| T1 | 104 (35.7%) | 6,403 (46.7%) | 104 (35.7%) | 322 (36.6%) | |||
| T2 | 168 (57.7%) | 5,846 (42.7%) | 168 (57.7%) | 468 (53.2%) | |||
| T3 | 4 (1.4%) | 509 (3.7%) | 4 (1.4%) | 48 (5.5%) | |||
| T4 | 15 (5.2%) | 941 (6.9%) | 15 (5.2%) | 42 (4.8%) | |||
| T stages [2010–2014] | N=138 | N=13,490 | 0.001 | N=138 | N=423 | 0.014 | |
| T1a | 38 (27.5%) | 3,938 (29.2%) | 38 (27.5%) | 122 (28.8%) | |||
| T1b | 25 (18.1%) | 2,420 (17.9%) | 25 (18.1%) | 60 (14.2%) | |||
| T1NOS | 0 (0.0%) | 18 (0.1%) | 0 (0.0%) | 1 (0.2%) | |||
| T2 | 0 (0.0%) | 6 (0.0%) | – | – | |||
| T2a | 28 (20.3%) | 4,313 (32.0%) | 28 (20.3%) | 141 (33.3%) | |||
| T2b | 12 (8.7%) | 683 (5.1%) | 12 (8.7%) | 24 (5.7%) | |||
| T2NOS | 0 (0.0%) | 22 (0.2%) | 0 (0.0%) | 1 (0.2%) | |||
| T3 | 33 (23.9%) | 1,571 (11.6%) | 33 (23.9%) | 58 (13.7%) | |||
| T4 | 2 (1.4%) | 519 (3.8%) | 2 (1.4%) | 16 (3.8%) | |||
| N stages | <0.001 | 0.871 | |||||
| N0 | 487 (91.7%) | 25,210 (72.3%) | 487 (91.7%) | 1,461 (91.7%) | |||
| N1 | 21 (4.0%) | 4,812 (13.8%) | 21 (4.0%) | 57 (3.6%) | |||
| N2 | 23 (4.3%) | 4,744 (13.6%) | 23 (4.3%) | 75 (4.7%) | |||
| N3 | 0 (0.0%) | 109 (0.3%) | – | – | |||
| Stages [2000–2003] | N=102 | N=7,686 | 0.001 | N=102 | N=290 | 0.070 | |
| I | 81 (79.4%) | 4,746 (61.7%) | 81 (79.4%) | 220 (75.9%) | |||
| II | 6 (5.9%) | 934 (12.2%) | 6 (5.9%) | 10 (3.4%) | |||
| IIIA | 6 (5.9%) | 1,239 (16.1%) | 6 (5.9%) | 43 (14.8%) | |||
| IIIB | 9 (8.8%) | 767 (10.0%) | 9 (8.8%) | 17 (5.9%) | |||
| Stages [2004–2009] | N=291 | N=13,699 | 0.001 | N=291 | N=880 | 0.254 | |
| IA | 103 (35.4%) | 5,173 (37.8%) | 103 (35.4%) | 309 (35.1%) | |||
| IB | 152 (52.2%) | 3,825 (27.9%) | 152 (52.2%) | 420 (47.7%) | |||
| IIA | 1 (0.3%) | 633 (4.6%) | 1 (0.3%) | 5 (0.6%) | |||
| IIB | 15 (5.2%) | 1,324 (9.7%) | 15 (5.2%) | 70 (8.0%) | |||
| IIIA | 5 (1.7%) | 1,767 (12.9%) | 5 (1.7%) | 34 (3.9%) | |||
| IIIB | 15 (5.2%) | 977 (7.1%) | 15 (5.2%) | 42 (4.8%) | |||
| Stages [2010–2014] | N=138 | N=13,490 | 0.001 | N=138 | N=423 | 0.010 | |
| IA | 59 (42.8%) | 5,422 (40.2%) | 59 (2.8%) | 177 (41.8%) | |||
| IB | 26 (18.8%) | 3,031 (22.5%) | 26 (18.8%) | 135 (31.9%) | |||
| II | 0 (0.0%) | 7 (0.1%) | – | – | |||
| IIA | 11 (8.0%) | 1,530 (11.3%) | 11 (8.0%) | 27 (6.4%) | |||
| IIB | 32 (23.2%) | 1,146 8.5%) | 32 (23.2%) | 54 (12.8%) | |||
| IIIA | 10 (7.2%) | 2,191 (16.2%) | 10 (7.2%) | 27 (6.4%) | |||
| IIIB | 0 (0.0%) | 163 (1.2%) | 0 (0.0%) | 3 (0.7%) | |||
| Operation | 0.063 | 0.011 | |||||
| Sublobar resection | 40 (7.5%) | 3,445 (9.9%) | 40 (7.5%) | 194 (12.2%) | |||
| Lobectomy | 477 (89.8%) | 30,106 (86.3%) | 477 (89.8%) | 1,352 (84.9%) | |||
| Pneumonectomy | 14 (2.6%) | 1,324 (3.8%) | 14 (2.6%) | 47 (3.0%) | |||
| Chemotherapy | 89 (16.8%) | 8,850 (25.4%) | <0.001 | 89 (16.8%) | 300 (18.8%) | 0.315 | |
| Radiation | 19 (3.6%) | 4,425 (12.8%) | <0.001 | 19 (3.6%) | 130 (8.2%) | 0.001 | |
| Treatment | <0.001 | 0.002 | |||||
| Surgery | 434 (81.7%) | 24,935 (71.5%) | 434 (81.7%) | 1,260 (79.1%) | |||
| Surgery + chemotherapy | 78 (14.7%) | 5,485 (15.7%) | 78 (14.7%) | 203 (12.7%) | |||
| Surgery + radiation | 8 (1.5%) | 1,090 (3.1%) | 8 (1.5%) | 33 (2.1%) | |||
| Trimodality | 11 (2.1%) | 3,365 (9.6%) | 11 (2.1%) | 97 (6.1%) | |||
| Lung cancer death | 363 (31.6%) | 11,027 (31.6%) | >0.999 | 168 (31.6%) | 477 (29.9%) | 0.496 | |
| All-cause mortality | 224 (42.2%) | 15,463 (43.7%) | 0.343 | 224 (42.2%) | 699 (43.9%) | 0.528 | |
*, data from the subset recorded from 2004; †, data from the subset recorded from 2010. IMA, invasive mucinous adenocarcinoma; LN, lymph nodes; NMA, nonmucinous adenocarcinoma.