Efficacy of chemotherapy containing bevacizumab in patients with metastatic colorectal cancer according to programmed cell death ligand 1

Table 1 Baseline characteristics

Characteristics
Number of patients	124
Age (yr)	56 (29-83)
Sex, n (%)
Male	69 (56)
Female	55 (44)
Tumor sidedness, n (%)
Right	32 (26)
Left	92 (74)
RAS mutational status, n (%)
Wild type	64 (52)
Mutation	60 (48)
TMB status, n (%)
TMB-low	99 (80)
TMB-high	25 (20)
Status of MSI (by IHC), n (%)
MSS	120 (97)
MSI-high	4 (3)
PD-L1 status, n (%)
PD-L1 CPS ≥ 1	105 (85)
PD-L1 CPS ≥ 5	64 (52)
PD-L1 CPS ≥ 10	32 (26)
Chemotherapy backbone with bevacizumab as first-line treatment, n (%)
FOLFOX	96 (77)
FOLFIRI	28 (23)

RAS: Rat sarcoma; TMB: Tumor mutational burden; MSI: Microsatellite instability; IHC: Immunohistochemistry; MSS: Microsatellite stability; PD-L1: Programmed cell death ligand 1; CPS: Combined positive score.

Table 2 Tumor response to first-line chemotherapy containing bevacizumab, n (%)

Response
CR	3 (3)
PR	51 (41)
SD	56 (45)
PD	9 (7)
Unknown	5 (4)

CR: Complete response; PR: Partial response; SD: Stable disease; PD: Disease progression.

Table 3 Progression-free survival and overall survival according to programmed cell death ligand 1 expression level

	Patients, n (%)	Progression-free survival (months)	P value2	Overall survival (months)	P value2
PD-L1 CPS < 11	19 (15)	22.4 (15.63-27.30)	P = 0.152	33.7 (NA)	P = 0.863
PD-L1 CPS ≥ 1	105 (85)	13.2 (14.91-20.10)		35.9 (16.84-55.02)
PD-L1 CPS < 5	60 (48)	16.7 (15.80-22.60)	P = 0.409	49.6 (20.89-78.97)	P = 0.746
PD-L1 CPS ≥ 5	64 (52)	12.1 (13.81-20.47)		30.1 (24.96-34.24)
PD-L1 CPS < 10	92 (74)	13.7 (15.35-20.77)	P = 0.529	49.9 (32.10-67.77)	P = 0.529
PD-L1 CPS ≥ 10	32 (26)	13.5 (13.52-23.45)		29.6 (21.65-37.49)

¹Programmed cell death ligand 1 expression was evaluated with various immunohistochemistry platforms using 22C3 antibody and determined with combined positive score.

²Kaplan-Meier methods and Cox-proportional hazards models were used for calculating P values and hazard ratios.

PD-L1: Programmed cell death ligand 1; CPS: Combined positive score.