Table 3.

Comparison of baseline PD-L1 expression and CD8+ TILs in patients with EGFR versus KRAS mutations

EGFR-mutant (N = 62)KRAS-mutant (N = 65)P
PD-L1 positive
 PD-L1+ (≥50%)7 (11%)11 (17%)0.449
 PD-L1+ (≥5%)10 (16%)20 (31%)0.062
CD8+ TILs (IHC)a
 017 (35%)18 (32%)0.159
 1+29 (60%)26 (46%)
 2+2 (4.2%)11 (20%)
 3+0 (0%)1 (1.8%)
CD8+ TILs (image-based)b per mm2
 Median185.1330.10.011
 (Range)(6.1–1,161.9)(8.5–2,567.3)
Concurrent PD-L1 expression & CD8+ TILs (IHC)
 PD-L1+ (≥50%) & high CD8+ TILs (grade 2–3)1/48 (2.1%)7/56 (12%)0.066
 PD-L1+ (≥5%) & high CD8+ TILs (grade 2–3)1/48 (2.1%)11/56 (20%)0.005
Concurrent PD-L1 expression & CD8+ TILs (image-based)
 PD-L1+ (≥50%) & highc CD8+ TILs per mm22/46 (4.3%)10/56 (18%)0.061
 PD-L1+ (≥5%) & highc CD8+ TILs per mm22/46 (4.3%)15/56 (27%)0.003
  • NOTE: Slight differences in the number of specimens analyzed using IHC versus quantitative CD8 analysis reflect differences in tissue adequacy for analysis. Percentages may not equal 100% due to rounding.

  • aCytology specimens and those with no tissue on the slide were excluded from the evaluation of CD8+ TILs.

  • bCytology and markedly fragmented biopsy specimens and those with no tissue on the slide were excluded from the evaluation of CD8+ TILs.

  • cHigh CD8+ TILs defined as ≥median in the pretreatment control (KRAS-mutant) population (330.1/mm2).