Table 2.
Association of tumor microenvironmental features with PD-L1 expression by tumor cellsa or infiltrating immune cells
| Parameter (no. specimens examined) | Tumor cells | Infiltrating immune cells | |||||
|---|---|---|---|---|---|---|---|
| Specimens n (%) |
PD-L1(−) n (%) |
PD-L1(+)b n (%) |
p-valuec | PD-L1(−) n (%) |
PD-L1(+)b n (%) |
p-valuec | |
| Tumor type (n=68) | |||||||
| melanoma | 30 (44) | 14 (47) | 16 (53) | 0.005 | 15 (50) | 15 (50) | 0.007 |
| non-small cell lung cancer | 17 (25) | 8 (47) | 9 (53) | 8 (47) | 9 (53) | ||
| kidney cancer | 9 (13) | 1 (11) | 8 (89) | 0 (0) | 9 (100) | ||
| colorectal cancer | 8 (12) | 7 (87) | 1 (13) | 4 (50) | 4 (50) | ||
| castration-resistant prostate ca. | 4 (6) | 4 (100) | 0 (0) | 4 (100) | 0 (0) | ||
| Tumor site (n=68) | |||||||
| lymph node | 17 (25) | 11 (65) | 6 (35) | 0.219 | 10 (59) | 7 (41) | 0.339 |
| lung | 15 (22) | 5 (33) | 10 (67) | 5 (33) | 10 (67) | ||
| other | 36 (53) | 18 (50) | 18 (50) | 16 (44) | 20 (56) | ||
| Primary vs. metastatic tumor (n=68) | |||||||
| primary | 29 (43) | 17 (59) | 12 (41) | 0.327 | 15 (52) | 14 (48) | 0.463 |
| metastasis | 39 (57) | 17 (44) | 22 (56) | 16 (41) | 23 (59) | ||
| Immune infiltrate scored (n=68) | |||||||
| 0 | 14 (21) | 13 (93) | 1 (7) | 0.001 | N/A | N/A | 0.69 |
| 1 | 35 (51) | 16 (46) | 19 (54) | 12 (34) | 23 (66) | ||
| 2 | 16 (24) | 5 (31) | 11 (69) | 5 (31) | 11 (69) | ||
| 3 | 3 (4) | 0 (0) | 3 (100) | 0 (0) | 3 (100) | ||
| Proportion of TILs expressing PD-1e(n=63) | |||||||
| 0 | 38 (60) | 25 (66) | 13 (34) | 0.001 | 22 (58) | 16 (42) | 0.005 |
| 1 | 13 (21) | 5 (38) | 8 (62) | 4 (31) | 9 (69) | ||
| 2 | 12 (19) | 1 (8) | 11 (92) | 1 (8) | 11 (92) | ||
| 3 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | ||
| CD4:CD8 ratio (n=50) | |||||||
| CD4≥CD8 | 22 (44) | 9 (41) | 13 (59) | 0.565 | 7 (32) | 15 (68) | 1.000 |
| CD4<CD8 | 28 (56) | 9 (32) | 19 (68) | 10 (36) | 18 (64) | ||
| CD20+ B-cells (n=51) | |||||||
| absent | 34 (67) | 23 (68) | 11 (32) | 0.006 | 21 (62) | 13 (38) | 0.017 |
| presentf | 17 (33) | 4 (24) | 13 (76) | 4 (24) | 13 (76) | ||
| Lymphoid aggregates (n=68) | |||||||
| absent | 58 (85) | 32 (55) | 26 (45) | 0.083 | 30 (52) | 28 (48) | 0.017 |
| present | 10 (15) | 2 (20) | 8 (80) | 1 (10) | 9 (90) | ||
| Necrosis (n=68) | |||||||
| absent | 50 (74) | 27 (54) | 23 (46) | 0.41 | 25 (50) | 25 (50) | 0.276 |
| present | 18 (26) | 7 (39) | 11 (61) | 6 (33) | 12 (67) | ||
| Small sample (n=68) | |||||||
| no | 44 (65) | 19 (43) | 25 (57) | 0.204 | 17 (39) | 27 (61) | 0.135 |
| yes | 24 (35) | 15 (62) | 9 (38) | 14 (58) | 10 (42) | ||
N/A, Not applicable; TIL, tumor infiltrating lymphocytes
Tumor cell PD-L1 expression was previously reported for 53 of these 68 specimens.(16)
Tumor or infiltrating immune cells were considered PD-L1(+) if ≥5% of cells had membranous (cell surface) PD-L1 expression.
Fisher’s exact test, two-sided, comparing PD-L1(+) vs. (−) specimens for the indicated parameter.
Immune infiltrates include tumor infiltrating lymphocytes (TILs) and accompanying histiocytes. Infiltrates were scored as “none” (0), “focal” (1), “moderate” (2), or “severe” (3) (See Methods).
Proportion 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 TIL, or where TIL were present but did not express PD-1.
CD20 “present” refers to any grade (“focal”, “moderate”, or “severe”).