Chemotherapy regimens with immunotherapy in advanced gastric cancer: A prognostic study using Cox modeling

Table 1 Basic patient characteristics and short-term efficacy, n (%)

Characteristic	Overall (n = 298)	PSOX (n = 150)	FOLFOX (n = 42)	SOX + XDL (n = 106)	Statistic	P value
Age					χ2 = 0.48	0.788
≤ 60	163 (54.7)	84 (56.0)	21 (50.0)	58 (54.7)
> 60	135 (45.3)	66 (44.0)	21 (50.0)	48 (45.3)
Sex					χ2 = 3.25	0.197
Male	235 (78.9)	121 (80.7)	36 (85.7)	78 (73.6)
Female	63 (21.1)	29 (19.3)	6 (14.3)	28 (26.4)
ASA					χ2 = 1.07	0.587
1 + 2	259 (86.9)	128 (85.3)	36 (85.7)	95 (89.6)
3	39 (13.1)	22 (14.7)	6 (14.3)	11 (10.4)
Differentiation					χ2 = 1.31	0.860
Well	128 (43.0)	65 (43.3)	16 (38.1)	47 (44.3)
Moderate	87 (29.2)	44 (29.3)	15 (35.7)	28 (26.4)
Poorly	83 (27.9)	41 (27.3)	11 (26.2)	31 (29.2)
cT stage					χ2 = 4.58	0.333
2	154 (51.7)	75 (50.0)	21 (50.0)	58 (54.7)
3	73 (24.5)	44 (29.3)	9 (21.4)	20 (18.9)
4	71 (23.8)	31 (20.7)	12 (28.6)	28 (26.4)
cN stage					χ2 = 0.04	0.979
Positive	210 (70.5)	106 (70.7)	30 (71.4)	74 (69.8)
Negative	88 (29.5)	44 (29.3)	12 (28.6)	32 (30.2)
cTNM
IIB	152 (51.0)	67 (44.7)	25 (59.5)	60 (56.6)
IIIA	52 (17.4)	35 (23.3)	7 (16.7)	10 (9.4)
IIIB	64 (21.5)	29 (19.3)	7 (16.7)	28 (26.4)
IIIC	30 (10.1)	19 (12.7)	3 (7.1)	8 (7.5)
RECIST1.1					χ2 = 3.73	0.155
Effective	183 (61.4)	91 (60.7)	21 (50.0)	71 (67.0)
Ineffective	115 (38.6)	59 (39.3)	21 (50.0)	35 (33.0)
Lauren					χ2 = 3.47	0.483
Diffuse	101 (33.9)	54 (36.0)	12 (28.6)	35 (33.0)
Mixed	142 (47.7)	65 (43.3)	21 (50.0)	56 (52.8)
Intestinal	55 (18.5)	31 (20.7)	9 (21.4)	15 (14.2)
Location					χ2 = 0.83	0.934
Upper	69 (23.2)	32 (21.3)	10 (23.8)	27 (25.5)
Middle	120 (40.3)	61 (40.7)	18 (42.9)	41 (38.7)
Lower	109 (36.6)	57 (38.0)	14 (33.3)	38 (35.8)
TRG					χ2 = 6.08	0.048
Effective	226 (75.8)	108 (72.0)	29 (69.0)	89 (84.0)
Ineffective	72 (24.2)	42 (28.0)	13 (31.0)	17 (16.0)
Tumor diameter					χ2 = 6.11	0.191
≤ 2	115 (38.6)	59 (39.3)	11 (26.2)	45 (42.5)
2-5	60 (20.1)	34 (22.7)	7 (16.7)	19 (17.9)
≥ 5	123 (41.3)	57 (38.0)	24 (57.1)	42 (39.6)

χ² test: Tumor location is classified as upper 1/3, middle 1/3, lower 1/3, diffuse TNM staging according to the American Joint Committee on Cancer. ASA: American Society of Anesthesiologists Score; FOLFOX: Oxaliplatin plus leucovorin and fluorouracil; PSOX: Plus oxaliplatin and S-1; RECIST: Response Evaluation Criteria in Solid Tumors; SOX + XDL: S-1 combined with sintilimab and oxaliplatin; TRG: Tumor regression grade.

Table 2 Side effects associated with three groups treatment, n (%)

Variables	Total (n = 298)	FOLFOX (n = 42)	PSOX (n = 150)	SOX + XDL (n = 106)	P value
Nausea and vomiting					0.186
0	62 (20.81)	3 (7.14)	36 (24.00)	23 (21.70)
1	178 (59.73)	29 (69.05)	86 (57.33)	63 (59.43)
2	51 (17.11)	8 (19.05)	26 (17.33)	17 (16.04)
3	7 (2.35)	2 (4.76)	2 (1.33)	3 (2.83)
Liver toxicity					0.442
0	252 (84.56)	34 (80.95)	125 (83.33)	93 (87.74)
1	41 (13.76)	6 (14.29)	23 (15.33)	12 (11.32)
2	5 (1.68)	2 (4.76)	2 (1.33)	1 (0.94)
Alopecia					0.002
0	176 (59.06)	21 (50.00)	78 (52.00)	77 (72.64)
1	105 (35.23)	20 (47.62)	58 (38.67)	27 (25.47)
2	17 (5.70)	1 (2.38)	14 (9.33)	2 (1.89)
Peripheral sensory neuropathy					0.912
0	147 (49.33)	23 (54.76)	75 (50.00)	49 (46.23)
1	121 (40.60)	15 (35.71)	61 (40.67)	45 (42.45)
2	25 (8.39)	4 (9.52)	12 (8.00)	9 (8.49)
3	5 (1.68)	0 (0.00)	2 (1.33)	3 (2.83)
Fewer neutrophils					0.123
0	213 (71.48)	25 (59.52)	114 (76.00)	74 (69.81)
1	55 (18.46)	12 (28.57)	24 (16.00)	19 (17.92)
2	19 (6.38)	3 (7.14)	5 (3.33)	11 (10.38)
3	10 (3.36)	2 (4.76)	6 (4.00)	2 (1.89)
4	1 (0.34)	0 (0.00)	1 (0.67)	0 (0.00)
Fewer white blood cells					0.352
0	192 (64.43)	25 (59.52)	100 (66.67)	67 (63.21)
1	68 (22.82)	11 (26.19)	28 (18.67)	29 (27.36)
2	27 (9.06)	5 (11.90)	13 (8.67)	9 (8.49)
3	7 (2.35)	0 (0.00)	6 (4.00)	1 (0.94)
4	4 (1.34)	1 (2.38)	3 (2.00)	0 (0.00)
Fewer platelets					0.106
0	213 (71.48)	29 (69.05)	111 (74.00)	73 (68.87)
1	57 (19.13)	9 (21.43)	25 (16.67)	23 (21.70)
2	23 (7.72)	1 (2.38)	12 (8.00)	10 (9.43)
3	5 (1.68)	3 (7.14)	2 (1.33)	0 (0.00)
Anemia					0.429
0	150 (50.34)	21 (50.00)	79 (52.67)	50 (47.17)
1	108 (36.24)	13 (30.95)	54 (36.00)	41 (38.68)
2	26 (8.72)	3 (7.14)	12 (8.00)	11 (10.38)
3	14 (4.70)	5 (11.90)	5 (3.33)	4 (3.77)

FOLFOX: Oxaliplatin plus leucovorin and fluorouracil; PSOX: Plus oxaliplatin and S-1; SOX + XDL: S-1 combined with sintilimab and oxaliplatin.

Table 3 Results of multivariate Cox proportional hazards regression analyses

Variables	n	Event N	HR	95%CI	P value
Differentiation
Well	61	29	-	-
Moderate	57	37	1.27	0.78-2.09	0.340
Poorly	91	75	1.86	1.19-2.91	0.006
cN stage
Negative	59	30	-	-
Positive	150	111	1.69	1.11, 2.57	0.013
cTNM
IIB	102	50	-	-
IIIA	21	15	1.49	0.81-2.72	0.199
IIIB	48	42	2.14	1.39-3.28	< 0.001
IIIC	38	34	3.94	2.47-6.28	< 0.001
RECIST1.1
Ineffective	81	68	-	-
Effective	128	73	0.65	0.46-0.92	0.016
TRG
Ineffective	53	46	-	-
Effective	156	95	0.56	0.39-0.82	0.003

HR: Hazard ratio; RECIST: Response Evaluation Criteria in Solid Tumors; TRG: Tumor regression grade.