Prognostic factors and optimal timing for initiating adjuvant chemotherapy in stage IIIC gastric cancer

Table 1 Comparison of clinicopathological characteristics between stage IIIB (n = 60) and stage IIIC (n = 62) gastric cancer patients, n (%)

Variable	Stage IIIB	Stage IIIC	P value
Gender
Female	15 (25.0)	20 (32.3)	0.376
Male	45 (75.0)	42 (67.7)
Age (years)
< 60	27 (45.0)	27 (43.5)	0.872
≥ 60	33 (55.0)	35 (56.5)
Tumor location
Upper	25 (41.7)	24 (40.2)	0.864
Middle	7 (11.7)	9 (13.1)
Lower	28 (46.6)	29 (46.7)
Atrophic gastritis
No	45 (75.0)	42 (67.7)	0.376
Yes	15 (25.0)	20 (32.3)
CEA (μg/L)
< 5	47 (78.3)	44 (71.0)	0.350
≥ 5	13 (21.7)	18 (29.0)
CA19-9 (kU/L)
< 37	45 (75.0)	43 (69.4)	0.487
≥ 37	15 (25.0)	19 (30.6)
CA125 (kU/L)
< 35	58 (96.7)	62 (100)	0.147
≥ 35	2 (3.3)	0 (0.0)
PLR
< 154	21 (35.0)	23 (37.1)	0.809
≥ 154	39 (65.0)	39 (62.9)
NLR
< 2.15	27 (45.0)	29 (46.8)	0.844
≥ 2.15	33 (55.0)	33 (53.2)
pT stage
T3	20 (33.3)	8 (12.9)	0.014
T4a	37 (61.7)	50 (80.6)
T4b	3 (5.0)	4 (6.5)
Pathological Ki-67
Low	14 (23.3)	15 (24.2)	0.911
High	46 (76.7)	47 (75.8)
HER-2
Low	52 (86.7)	59 (95.2)	0.101
High	8 (13.3)	3 (4.8)
EBER
Negative	52 (86.7)	57 (91.9)	0.346
Positive	8 (13.3)	5 (8.1)
P53
Low	33 (55.0)	35 (56.5)	0.872
High	27 (45.0)	27 (43.5)
pMMR
No	2 (3.3)	5 (8.1)	0.463
Yes	58 (96.7)	57 (91.9)
LVI
No	18 (30.0)	7 (11.3)	0.010
Yes	42 (70.0)	55 (88.7)
Tumor size (cm)
< 5	36 (60.0)	22 (35.5)	0.007
≥ 5	24 (40.0)	40 (64.5)
Histological differentiation
Others	20 (33.3)	1 (1.6)	< 0.001
Poorly-differentiated	40 (66.7)	61 (98.4)
Borrmann classification
Type I	6 (10.0)	3 (4.8)	0.014
Type II	42 (70.0)	36 (58.1)
Type III	9 (15.0)	9 (14.5)
Type IV	3 (5.0)	14 (22.6)
MLR
< 0.5	52 (86.7)	18 (29.0)	< 0.001
≥ 0.5	8 (13.3)	44 (71.0)
pN stage
2	2 (3.3)	0 (0.0)	< 0.001
3a	58 (96.7)	1 (1.6)
3b	0 (0.0)	61 (98.4)
Cycle (week)
6	34 (56.7)	28 (45.2)	0.071
8	23 (38.3)	22 (35.5)
12	3 (5)	12 (19.3)
TI (week)
< 4	9 (15)	13 (21.0)	0.055
< 6	26 (43.3)	28 (45.2)
< 8	9 (15)	1 (1.6)
≥ 8	16 (26.7)	20 (32.2)

CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9; CA125: Carbohydrate antigen 125; PLR: Platelet-to-lymphocyte ratio; NLR: Neutrophil-to-lymphocyte ratio; pT: Pathological T; EBER: Epstein-Barr virus-encoded small RNA status; HER-2: Human epidermal growth factor receptor-2; pMMR: Proficient mismatch repair or deficient mismatch repair; LVI: Lymphatic and/or blood vessel invasion status; MLR: Metastatic lymph node ratio; pN: Pathological N; TI: Time interval.

Table 2 Univariate and multivariate analyses of clinicopathologic factors for disease-free survival of patients with stage IIIC gastric cancer

Variable	Univariate analysis		Multivariate analysis
	HR (95%CI)	P value	HR (95%CI)	P value
Gender	1.170 (0.594-2.305)	0.649	-	-
Age (years)	4.776 (2.253-10.126)	< 0.001	5.151 (2.200-12.060)	< 0.001
Tumor location	0.815 (0.581-1.142)	0.234	-	-
BMI	0.841 (0.489-1.448)	0.532	-	-
Atrophic gastritis	0.985 (0.514-1.888)	0.965	-	-
CEA (μg/L)	2.833 (1.486-5.401)	0.002	2.997 (1.404-6.400)	0.005
CA19-9 (kU/L)	1.682 (0.875-3.232)	0.119	-	-
PLR	0.954 (0.502-1.812)	0.886	-	-
NLR	1.726 (0.909-3.278)	0.095	-	-
pT stage	1.119 (0.564-2.221)	0.748	-	-
Ki-67	0.993 (0.485 2.031)	0.984	-	-
HER-2	0.043 (0.001-7.247)	0.230	-	-
EBER	1.494 (0.530-4.213)	0.448	-	-
P53	0.825 (0.440-1.545)	0.548	-	-
pMMR	0.380 (0.091-1.583)	0.184	-	-
Vascular invasion	0.980 (0.383-2.507)	0.966	-	-
Nerve invasion	0.798 (0.284-2.247)	0.670	-	-
Tumor size (cm)	0.718 (0.380-1.353)	0.305	-	-
Histological differentiation	0.283 (0.037-2.144)	0.222	-	-
Borrmann classification	1.185 (0.855-1.642)	0.309	-	-
MLR	2.481 (1.094-5.624)	0.030	2.404 (1.048-5.519)	0.039
TI	1.014 (1.006-1.021)	< 0.001	1.002 (1.000-1.005)	0.046
Cycle	0.355 (0.211-0.597)	< 0.001	0.667 (0.372-1.195)	0.174

HR: Hazard ratio; CI: Confidence interval; BMI: Body mass index; CEA: Carcinoembryonic antigen; CA19-9: Carbohydrate antigen 19-9; PLR: Platelet-to-lymphocyte ratio; NLR: Neutrophil-to-lymphocyte ratio; pT: Pathological T; EBER: Epstein-Barr virus-encoded small RNA status; HER-2: Human epidermal growth factor receptor-2; pMMR: Proficient mismatch repair or deficient mismatch repair; MLR: Metastatic lymph node ratio; TI: Time interval.