Table 1 Baseline characteristics of ES-SCLC patients before and after PSM
Characteristic | Before matching | Characteristic | After matching | ||||
|---|---|---|---|---|---|---|---|
TRT Group (n = 117) | non-TRT Group (n = 159) | P value | TRT Group (n = 99) | non-TRT Group (n = 98) | P value | ||
Age, years | Â | Â | 0.363 | Age, years | Â | Â | 0.939 |
 < 60 | 55(47.0%) | 66(41.5%) |  |  < 60 | 46(46.5%) | 45(45.9%) |  |
 ≥60 | 62(53.0%) | 93(58.5%) |  |  ≥60 | 53(53.5%) | 53(54.1%) |  |
Gender | Â | Â | 0.135 | Gender | Â | Â | 0.492 |
 Male | 92(78.6%) | 136(85.5%) |  |  Male | 78(78.8%) | 81(82.7%) |  |
 Female | 25(21.4%) | 23(14.5%) |  |  Female | 21(21.2%) | 17(17.3%) |  |
Smoking history | Â | Â | 0.486 | Smoking history | Â | Â | 0.821 |
 Yes | 65(55.6%) | 95(59.7%) |  |  Yes | 56(56.6%) | 57(58.2%) |  |
 No | 52(44.4%) | 64(40.3%) |  |  No | 43(43.4%) | 41(41.8%) |  |
ECOG PS | Â | Â | 0.08 | ECOG PS | Â | Â | 0.418 |
 0–1 | 92(78.6%) | 110(69.2%) |  |  0–1 | 74(74.7%) | 78(79.6%) |  |
 2 | 25(21.4%) | 49(30.8%) |  |  2 | 25(25.3%) | 20(20.4%) |  |
T stage | Â | Â | 0.909 | T stage | Â | Â | 0.832 |
 T1-T2 | 61(52.1%) | 84(52.8%) |  |  T1-T2 | 48(48.5%) | 49(50.0%) |  |
 T3-T4 | 56(47.9%) | 75(47.2%) |  |  T3-T4 | 51(51.5%) | 49(50.0%) |  |
N stage | Â | Â | 0.387 | N stage | Â | Â | 0.434 |
 N0-N2 | 61(52.1%) | 73(45.9%) |  |  N0-N2 | 53(53.5%) | 47(48.0%) |  |
 N3 | 56(47.9%) | 86(54.1%) |  |  N3 | 46(46.5%) | 51(52.0%) |  |
M stage | Â | Â | 0.002 | M stage | Â | Â | 0.665 |
 M1a | 24 (20.5%) | 21 (13.2%) |  |  M1a | 19 (19.2%) | 17 (17.4%) |  |
 M1b | 72 (61.5%) | 80 (50.3%) |  |  M1b | 60 (60.6%) | 56 (57.1%) |  |
 M1c | 21 (18.0%) | 58 (36.5%) |  |  M1c | 20 (20.2%) | 25 (25.5%) |  |
Type of ICIs | Â | Â | 0.652 | Type of ICIs | Â | Â | 0.793 |
 PD-1 | 36(30.8%) | 53(33.3%) |  |  PD-1 | 31(31.3%) | 29(29.6%) |  |
 PD-L1 | 81(69.2%) | 106(66.7%) |  |  PD-L1 | 68(68.7%) | 69(70.4%) |  |
NO. of metastatic sites | Â | Â | 0.004 | NO. of metastatic sites | Â | Â | 0.837 |
 ≤ 2 | 106(90.6%) | 123(77.4%) |  |  ≤ 2 | 88(88.9%) | 88(89.8%) |  |
 > 2 | 11(9.4%) | 36(22.6%) |  |  > 2 | 11(11.1%) | 10(10.2%) |  |
Brain metastases | Â | Â | 0.295 | Brain metastases | Â | Â | 0.725 |
 Yes | 40(34.2%) | 45(28.3%) |  |  Yes | 33(33.3%) | 35(35.7%) |  |
 No | 77(65.8%) | 114(71.7%) |  |  No | 66(66.7%) | 63(64.3%) |  |
Liver metastases |  |  | < 0.001 | Liver metastases |  |  | 0.899 |
 Yes | 24(20.5%) | 66 (41.5%) |  |  Yes | 24(24.2%) | 23(23.5%) |  |
 No | 93(79.5%) | 93(58.5%) |  |  No | 75(75.8%) | 75(76.5%) |  |
Bone metastases | Â | Â | 0.039 | Bone metastases | Â | Â | 0.596 |
 Yes | 27(23.1%) | 55(34.6%) |  |  Yes | 24(24.2%) | 27(27.6%) |  |
 No | 90(76.9%) | 104(65.4%) |  |  No | 75(75.8%) | 71(72.4%) |  |
Response evaluation* | Â | Â | 0.794 | Response evaluation* | Â | Â | 0.758 |
 CR/PR | 81(69.2%) | 107(67.3%) |  |  CR/PR | 67(67.7%) | 69(70.4%) |  |
 SD | 36(30.8%) | 52(32.7%) |  |  SD | 32(32.3%) | 29(29.6%) |  |