1Department of Thoracic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
2Merck & Co., Inc., Kenilworth, NJ, USA
3Department of Pathology and Translational Genomics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
4Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
Copyright © 2018 by the Korean Cancer Association
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Subgroup | No. | PD-L1 expression status |
Chi-square p-value | ||
---|---|---|---|---|---|
TPS ≥ 50% | TPS 1%-49% | Negative | |||
Overall | 319 | 24 (8) | 139 (44) | 156 (49) | |
Sex | |||||
Male | 125 | 13 (10) | 64 (51) | 48 (38) | 0.008 |
Female | 194 | 11 (6) | 75 (39) | 108 (56) | |
Smoking status | |||||
Never | 205 | 11 (5) | 82 (40) | 112 (55) | 0.011 |
Smokers | 114 | 13 (11) | 57 (50) | 44 (39) | |
ECOG PS | |||||
0 | 202 | 12 (6) | 88 (44) | 102 (51) | 0.345 |
1 | 116 | 12 (10) | 50 (43) | 54 (47) | |
Disease stage at baseline | |||||
IA | 153 | 6 (4) | 61 (40) | 86 (56) | 0.006 |
IB | 48 | 1 (2) | 20 (42) | 27 (56) | |
II | 41 | 7 (17) | 20 (49) | 14 (34) | |
III | 61 | 9 (15) | 29 (48) | 23 (38) | |
IV | 16 | 1 (6) | 9 (56) | 6 (38) | |
EGFR mutation | |||||
Exon 19 deletion | 145 | 9 (6) | 67 (46) | 69 (48) | 0.001 |
Exon 21 L858R | 121 | 9 (7) | 38 (31) | 74 (61) | |
Others |
53 | 6 (11) | 34 (64) | 13 (25) |
Survival | HR (95% CI) |
|
---|---|---|
PD-L1 TPS ≥ 50% (n=24) | PD-L1 TPS 1%-49% (n=139) | |
RFS | ||
Unadjusted HR (95% CI) | 3.07 (1.74-5.42) | 1.89 (1.31-2.74) |
Adjusted for baseline prognostic factors |
1.60 (0.88-2.93) | 1.49 (1.02-2.18) |
Adjusted for baseline prognostic factors plus treatment |
1.52 (0.81-2.84) | 1.51 (1.02-2.21) |
OS | ||
Unadjusted HR (95% CI) | 2.70 (1.07-6.66) | 1.04 (0.57-1.89) |
Adjusted for baseline prognostic factors |
1.25 (0.46-3.44) | 0.94 (0.5-1.76) |
Adjusted for baseline prognostic factors plus treatment |
1.29 (0.45-3.72) | 0.93 (0.49-1.74) |
Values are presented as number (%). PD-L1, programmed death ligand 1; TPS, tumor proportion score; ECOG PS, Eastern Cooperative Oncology Group performance status; Exon 19, nondeletion (n=26); exon 21, non-L858R mutation (n=3); exon 18 (n=12); exon 20 (n=8); one patient had mutations in both exons 18 and 20, and three patients had other mutations. Among those (n=53), median age was 60.0 years (range, 44 to 84 years), 51% were women (n=27), 49% were men (n=26), 51% were never smokers (n=27), and 49% were smokers (n=26). Most patients had early-stage disease, including 57% (n=30) stage I, 9% (n=5) stage II, 32% (n=17) stage III, and 2% (n=1) were stage IV.
RFS, recurrence-free survival; OS, overall survival; HR, hazard ratio; CI, confidence interval; PD-L1, programmed death ligand 1; TPS, tumor proportion score. PD-L1 negative was used as the reference population (n=156), Baseline prognostic factors included age, sex, smoking status, stage, and Eastern Cooperative Oncology Group performance status (Cox model 1), Included baseline prognostic factors and treatment (Cox model 2).