High tumoral PD-L1 expression and low PD-1⁺ or CD8⁺ tumor-infiltrating lymphocytes are predictive of a poor prognosis in primary diffuse large B-cell lymphoma of the central nervous system

Figures & data

Figure 1. Tumoral and non-tumoral PD-L1 expression is positively correlated with the numbers of CD8⁺ and PD-1⁺ TILs. (a) Representative IHC images of PD-L1, PD-1, and CD8. PD-L1 was expressed on tumor cells (A-1–4) and surrounding non-tumoral cells, primarily macrophages (A-5), concurrently or alone. CD8 and PD-1 were expressed on TILs (A-6–7), and PD-1 was expressed on tumor cells (A-8). Percentages of PD-L1⁺ cells of the tumor cells (tPD-L1, red bar) and those of PD-L1⁺ cells of the total cellularity including tumor cells and non-tumor cells (tmPD-L1, green bar) in each case are displayed (b). The correlation between the numbers of CD8⁺ TIL and PD-1⁺ TIL were assessed by Spearman correlation analysis (c). Numbers of CD8⁺ TILs and PD-1⁺ TILs in tPD-L1– and tPD-L1+ cases (d) and tmPD-L1 – and tmPD-L1+ cases (e). Differences were analyzed using the Mann-Whitney U test. Whiskers, 10th to 90th percentiles; midline of the box, median; +, mean. Points below and above the whiskers are individual points. Abbreviations: MΦ, macrophage; N, negative; P, positive.

Table 1. Clinicopathological characteristics of patients with PCNS-DLBCL.

Variable^a		n (%) (total = 98)
Age (years)	Median, 61 (range, 10–82)
Sex	Male Female	56 (57.1) 42 (42.9)
Initial symptoms	Headache & vomiting Seizure Neurological deficit	26 (26.5) 6 (6.1) 66 (67.3)
ECOG PS^a	0, 1 2–4	61 (62.9) 36 (37.1)
KPS^a	≥ 70 < 70	83 (86.5) 13 (13.5)
B Symptoms	Absent Present	94 (65.9) 4 (4.1)
Serum LDH^a	Normal Elevated	58 (61.7) 36 (38.3)
EBV	Negative Positive	25 (92.6) 2 (7.4)
Cell-of-origin^b	GCB Non-GCB	23 (23.5) 75 (76.5)
Involvement of deep structures^c	Absent Present	29 (29.6) 69 (70.4)
Extent of disease	Unifocal Multifocal	39 (39.8) 59 (60.2)
Ocular involvement^a	Absent Present	87 (89.7) 10 (10.3)
CSF protein^a	Normal Elevated	33 (40.7) 48 (59.3)
CSF cytology^a	Negative Positive	72 (85.7) 12 (14.3)
IELSG^a	0–1 2–3 4–5	12 (15.0) 51 (63.8) 17 (21.3)
Nottingham-Barcelona^a	0–1 2–3	48 (49.5) 49 (50.5)
MSKCC class^a	1 2 3	18 (18.6) 68 (70.1) 11 (11.3)
Prior steroid therapy	None ≤1 day >1 day, ≤3 days unknown	77 (78.6) 7 (7.1) 10 (10.2) 4 (4.1)
Radiotherapy	Not done Done	36 (31.6) 78 (68.4)
Chemotherapy	MVP^d HD-MTX Others^e	79 (81.4) 14 (14.4) 4 (4.1)
Rituximab	Not done Done	103 (90.4) 11 (9.6)
IT-MTX	Not done Done	89 (78.1) 25 (21.9)
Surgery	Biopsy Subtotal resection Gross total resection	8 (8.2) 74 (75.5) 16 (16.3)
MYC expression (% of tumor cells)	< 40 ≥ 40	78 (79.6) 20 (20.4)
BCL2 expression (% of tumor cells)	< 60 ≥ 60	41 (41.8) 57 (58.2)
MYC/BCL2 expression	Others Double expresser	82 (83.7) 16 (16.3)
MYD88 mutation^a	Wild-type Mutation	49 (64.5) 27 (35.5)
CD79B mutation^a	Wild-type Mutation	71 (77.2) 21 (22.8)

Abbreviations: CSF, cerebrospinal fluid; ECOG PS, Eastern Cooperative Oncology Group Performance GCB, germinal center B cell-like; HD-MTX, high-dose methotrexate; IELSG, International Extranodal Lymphoma Study Group; IT-MTX, intrathecal methotrexate; KPS, Karnofsky Performance Status score; LDH, lactate dehydrogenase; MSKCC, Memorial Sloan Kettering Cancer Center; MVP, chemotherapy regimen comprising high-dose methotrexate, vincristine, and procarbazine.

^aSome cases had missing values.

^bCell-of-origin was determined by Hans algorithm (Blood 2004;103:275–82).

^cDeep structures are the periventricular regions, basal ganglia, brain stem, and/or cerebellum.

^dIncluding eight patients who received rituximab-MVP.

^eOthers include COPADM and CHOP.

Figure 2. PD-L1 expression according to clinicopathological parameters. The percentages of tumoral PD-L1 (tPD-L1) and tumoral plus non-tumoral PD-L1 (tmPD-L1) were compared according to age (≤50, n = 21; >50, n = 77) (a), ECOG performance status (0–1, n = 61; 2–4, n = 36) (b), MSKCC class (class 1, n = 18; class 2, n = 68; class 3, n = 11) (c), MYC expression (<40, n = 78; ≥40, n = 20) (d), BCL2 expression (<60, n = 41; ≥60, n = 57) (e), and MYC/BCL2 expression status (NE, n = 37; SE, n = 45; DE, n = 16) (f). Differences were analyzed using Mann–Whitney U test and Kruskal–Wallis test and multiple test correction were done by Benjamini and Hochberg method. Adjusted P values were presented on graphs. Whiskers, 10th to 90th percentiles; midline of the box, median; +, mean. Points below and above the whiskers are individual points. Abbreviations: DE, double expresser; ECOG, Eastern Cooperative Oncology Group; MSKCC, Memorial Sloan Kettering Cancer Center; NE, non-expresser; SE, single expresser.

Figure 3. Numbers of CD8⁺ TILs and PD-1⁺ TILs according to clinicopathological parameters. The numbers of CD8⁺ TILs were compared according to age (≤50, n = 21; >50, n = 75) (a), ECOG performance status (0–1, n = 60; 2–4, n = 35) (b), MSKCC class (class 1, n = 18; class 2, n = 66; class 3, n = 11) (c), MYC expression (<40, n = 76; ≥40, n = 20) (d), BCL2 expression (<60, n = 40; ≥60, n = 56) (e), and MYC/BCL2 expression status (NE, n = 36; SE, n = 44; DE, n = 16) (f). The numbers of PD-1⁺ TILs were compared according to age (≤50, n = 19; >50, n = 71) (a), ECOG performance status (0–1, n = 57; 2–4, n = 32) (b), MSKCC class (class 1, n = 16; class 2, n = 64; class 3, n = 9) (c), MYC expression (<40, n = 72; ≥40, n = 18) (d), BCL2 expression (<60, n = 38; ≥60, n = 52) (e), and MYC/BCL2 expression status (NE, n = 35; SE, n = 40; DE, n = 15) (f). Differences were analyzed using Mann–Whitney U test and Kruskal–Wallis test and multiple test correction were done by Benjamini and Hochberg method. Adjusted P values were presented on graphs. Whiskers, 10th to 90th percentiles; midline of the box, median; +, mean. Points below and above the whiskers are individual points. *P< .05. Abbreviations: DE, double expresser; ECOG, Eastern Cooperative Oncology Group; MSKCC, Memorial Sloan Kettering Cancer Center; NE, non-expresser; SE, single expresser.

Figure 4. Prognostic significance of tPD-L1, CD8⁺ TILs, and PD-1⁺ TILs. Kaplan-Meier analysis of PFS and/or OS according to tPD-L1(tPD-L1-, n = 63; tPD-L1+ = 35) (a-b), CD8⁺ TILs (Low CD8+ TILs, n = 42; High CD8+ TILs, n = 54) (c), PD-1⁺ TILs (Low PD-1+ TILs, n = 44; High PD-1+ TILs, n = 46) (d), tPD-L1 plus CD8⁺ TILs (tPD-L1-/Low CD8+ TILs, n = 27; tPD-L1-/High CD8+ TILs, n = 34; tPD-L1+/Low CD8+ TILs, n = 15; tPD-L1+/High CD8+ TILs, n = 20) (e-f), and tPD-L1 plus PD-1⁺ TILs (tPD-L1-/Low PD-1+ TILs, n = 31; tPD-L1-/High PD-1+ TILs, n = 29; tPD-L1+/Low PD-1+ TILs, n = 13; tPD-L1+/High PD-1+ TILs, n = 17) (g-h). Differences in survival were analyzed by log-rank test. † P= .05–0.1, *P< .05.

Table 2. Multivariate analysis of overall survival (OS) in patients with PCNS-DLBCL.

	HR (95% CI)	P
Age	1.045 (1.013–1.077)	0.005
N-B score 2–3	1.977 (1.042–3.750)	0.037
MSKCC class	-	-
HD-MTX+RTx	0.582 (0.333–1.018)	0.058
MYC/BCL2 DE	-	-
tPD-L1+	1.896 (1.081–3.325)	0.026
High CD8^+ TILs	-	-
High PD-1^+ TILs	0.428 (0.241–0.763)	0.004

Abbreviations: CI, confidence interval; DE, double expresser; HD-MTX, high-dose methotrexate; MSKCC, Memorial Sloan Kettering Cancer Center; N-B, Nottingham–Barcelona; RTx, radiotherapy.