Table 2.

Association of tumor microenvironmental features with PD-L1 expression by tumor cellsa or infiltrating immune cells

Tumor cellsInfiltrating immune cells
Parameter (number of specimens examined)Specimensn (%)PD-L1(−)n (%)PD-L1(+)bn (%)P valuecPD-L1(−)n (%)PD-L1(+)bn (%)P valuec
Tumor type (n = 68)
 Melanoma30 (44)14 (47)16 (53)0.00515 (50)15 (50)0.007
 NSCLC17 (25)8 (47)9 (53)8 (47)9 (53)
 Kidney cancer9 (13)1 (11)8 (89)0 (0)9 (100)
 Colorectal cancer8 (12)7 (87)1 (13)4 (50)4 (50)
 CRPC4 (6)4 (100)0 (0)4 (100)0 (0)
Tumor site (n = 68)
 Lymph node17 (25)11 (65)6 (35)0.21910 (59)7 (41)0.339
 Lung15 (22)5 (33)10 (67)5 (33)10 (67)
 Other36 (53)18 (50)18 (50)16 (44)20 (56)
Primary vs. metastatic tumor (n = 68)
 Primary29 (43)17 (59)12 (41)0.32715 (52)14 (48)0.463
 Metastasis39 (57)17 (44)22 (56)16 (41)23 (59)
Immune infiltrate scored (n = 68)
 014 (21)13 (93)1 (7)0.001N/AN/A0.69
 135 (51)16 (46)19 (54)12 (34)23 (66)
 216 (24)5 (31)11 (69)5 (31)11 (69)
 33 (4)0 (0)3 (100)0 (0)3 (100)
Proportion of TILs expressing PD-1e (n = 63)
 038 (60)25 (66)13 (34)0.00122 (58)16 (42)0.005
 113 (21)5 (38)8 (62)4 (31)9 (69)
 212 (19)1 (8)11 (92)1 (8)11 (92)
 30 (0)0 (0)0 (0)0 (0)0 (0)
CD4:CD8 ratio (n = 50)
 CD4 ≥ CD822 (44)9 (41)13 (59)0.5657 (32)15 (68)1.000
 CD4 < CD828 (56)9 (32)19 (68)10 (36)18 (64)
CD20+ B cells (n = 51)
 Absent34 (67)23 (68)11 (32)0.00621 (62)13 (38)0.017
 Presentf17 (33)4 (24)13 (76)4 (24)13 (76)
Lymphoid aggregates (n = 68)
 Absent58 (85)32 (55)26 (45)0.08330 (52)28 (48)0.017
 Present10 (15)2 (20)8 (80)1 (10)9 (90)
Necrosis (n = 68)
 Absent50 (74)27 (54)23 (46)0.4125 (50)25 (50)0.276
 Present18 (26)7 (39)11 (61)6 (33)12 (67)
Small sample (n = 68)
 No44 (65)19 (43)25 (57)0.20417 (39)27 (61)0.135
 Yes24 (35)15 (62)9 (38)14 (58)10 (42)

Abbreviation: N/A, not applicable.

  • aTumor cell PD-L1 expression was previously reported for 53 of these 68 specimens (16).

  • bTumor or infiltrating immune cells were considered PD-L1(+) if ≥5% of cells had membranous (cell surface) PD-L1 expression.

  • cFisher exact test, two-sided, comparing PD-L1(+) versus (−) specimens for the indicated parameter.

  • dImmune infiltrates include TILs and accompanying histiocytes. Infiltrates were scored as “none” (0), “focal” (1), “moderate” (2), or “severe” (3; see Materials and Methods).

  • eProportion of TILs expressing PD-1 was graded as “none” (0), “focal” (1), “moderate” (2), or “severe” (3). A score of “0” includes cases where there were no TILs, or where TILs were present but did not express PD-1.

  • fCD20 “present” refers to any grade (“focal,” “moderate,” or “severe”).