Table 2.

PD-L1 expression in EGFR-mutant and ALK-rearranged lung cancer patients prior to and after TKI treatment

EGFR-mutantALK-rearranged
Pre-TKI (N = 62)Post-TKI (N = 63)PaPre-Criz (N = 19)Post-Criz (N = 12)Pa
PD-L1 positive
 PD-L1+ (≥50%)7 (11%)9 (14%)0.7275 (26%)2 (17%)1.000
 PD-L1+ (≥5%)10 (16%)18 (29%)0.1199 (47%)3 (25%)0.500
CD8+ TILs (IHC)b
 017 (35%)18 (42%)0.8472 (15%)4 (44%)*
 1+29 (60%)20 (47%)8 (62%)5 (56%)
 2+2 (4.2%)5 (12%)3 (23%)0 (0%)
 3+0 (0%)0 (0%)0 (0%)0 (0%)
CD8+ TILs (image-based)c per mm2
 Median185.1140.20.527178.969.2*
 (Range)(6.1–1,161.9)(4.3–1,029.3)(30.1–477.4)(17.9–523.6)
Concurrent PD-L1 expression & CD8+ TILs (IHC)
 PD-L1+ (≥50%) & high CD8+ TILs (grade 2–3)1/48 (2.1%)1/43 (2.3%)1.0000/13 (0%)0/9 (0%)*
 PD-L1+ (≥5%) & high CD8+ TILs (grade 2–3)1/48 (2.1%)5/43 (11.6%)0.2190/13 (0%)0/9 (0%)
Concurrent PD-L1 expression & CD8+ TILs (image-based)
 PD-L1+ (≥50%) & highd CD8+ TILs per mm22/46 (4.3%)1/35 (2.9%)1.0000/11 (0%)0/7 (0%)*
 PD-L1+ (≥5%) & highd CD8+ TILs per mm22/46 (4.3%)3/35 (8.6%)1.0001/11 (9.1%)0/7 (0%)
  • 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.

  • Abbreviation: Criz, crizotinib.

  • aAll P values are based upon paired sample analysis. *, P value not calculated based on limited pairs.

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

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

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