Prognostic value of perioperative leukocyte count in resectable gastric cancer

Table 1 Patient characteristics

Variables	n	%	Variables	n	%
All patients	614		pTNM stage
Age (yr)			I	76	12.4
Median (range)	58 (18-85)		II	149	24.3
Sex			III	354	57.7
Male	430	70.0	IV	35	5.7
Female	184	30.0	Vascular or neural invasion
Tumor site			Negative	337	54.9
Cardia	148	24.1	Positive	277	45.1
Fundus	10	1.6	Operation method
Body	241	39.3	Promixal gastrectomy	80	13.1
Antrum	193	31.4	Distal gastrectomy	295	48.0
Borrmann type			Total gastrectomy	239	38.9
I/II/III	578	94.1	Resection margins
IV	36	5.9	R0	436	71.0
Histology			R1	178	29.0
Differentiated	89	14.5	Chemotherapy regimens
Undifferentiated	525	85.5	Triplet	253	41.2
Tumor status			Doublet	295	48.0
pT1	51	8.3	Singlet	45	7.3
pT2	80	13.0	None	21	3.4
pT3	123	20.0	Intraoperative blood loss (mL)
pT4	360	58.6	Median (range)	120 (50-1500)
Node status			≤ 200	569	92.7
pN0	150	24.4	> 200	49	7.3
pN1	122	19.9	Intraoperative blood transfusion
pN2	158	25.7	No	537	87.5
pN3	184	30.0	Yes	77	12.5

Table 2 Blood cell counts pre- and postoperatively

Factors	mean ± SD	Range	P value	n (%)
				Low1	Normal1	High1
WBC (× 109/L)
Before operation	6.08 ± 2.11	1.5-17.3	< 0.001	54 (8.8)	530 (86.3)	30 (4.9)
After operation	5.25 ± 1.97	2.1-17.8		140 (22.8)	455 (74.1)	19 (3.1)
HGB (g/L)
Before operation	124.2 ± 22.92	55-176	< 0.001	159 (25.9)	441 (71.8)	14 (2.3)
After operation	117.1 ± 13.68	79-161		300 (48.9)	313 (51.0)	1 (0.2)
PLT (× 109/L)
Before operation	214.9 ± 77.15	55-706	0.838	22 (3.6)	527 (85.8)	65 (10.6)
After operation	214.2 ± 84.76	42-793		22 (3.6)	520 (84.7)	72 (11.7)

¹Low represents the values that were lower than the lower limit of the normal range; Normal represents the values that were within the normal range; High represents the values that were higher than the upper limit of the normal range. HGB: Hemoglobin; PLT: Platelet count; WBC: White blood cell count.

Table 3 Relationships between white blood cell count and patients’ clinicopathologic features n (%)

Factors	Preoperative WBC count (×109/L)		P value	P-leukopenia		P value
	< 5.6	≥5.6		Positive	Negative
All patients	295 (48.0)	319 (52.0)		107 (17.4)	507 (82.6)
Age (yr)
< 58	143 (51.1)	137 (48.9)	0.194	51 (18.2)	229 (81.8)	0.670
≥ 58	152 (45.5)	182 (54.5)		56 (16.8)	278 (83.2)
Sex
Male	192 (44.7)	238 (55.3)	0.011	70 (16.3)	360 (83.7)	0.248
Female	103 (56.0)	81 (44.0)		37 (20.1)	147 (79.9)
Tumor site
Cardia	74 (50.0)	74 (50.0)	0.823	29 (19.6)	119 (80.4)	0.664
Fundus	6 (60.0)	4 (40.0)		1 (10.0)	9 (90.0)
Body	112 (46.5)	129 (53.5)		39 (16.2)	202 (83.8)
Antrum	94 (48.7)	99 (51.3)		36 (18.7)	157 (81.3)
Multi-site	9 (40.9)	13 (59.1)		2 (9.1)	20 (90.9)
Histology
Differentiated	35 (39.3)	54 (60.7)	0.085	8 (9.0)	81 (91.0)	0.023
Undifferentiated	260 (49.5)	265 (50.5)		99 (18.9)	426 (81.1)
Borrmann type
I/II/III	278 (48.1)	300 (51.9)	0.919	101 (17.5)	477 (82.5)	0.901
IV	17 (47.2)	19 (52.8)		6 (16.7)	30 (83.3)
Tumor status
pT1 + pT2	78 (59.5)	53 (40.5)	0.003	18 (13.7)	113 (86.3)	0.198
pT3 + pT4	217 (44.9)	266 (55.1)		91 (18.8)	392 (81.2)
Node status
pN0	84 (56.0)	64 (44.0)	0.011	25 (16.7)	125 (83.3)	0.901
pN1 + pN2 + pN3	209 (45.0)	255 (55.0)		82 (17.7)	382 (82.3)
pTNM stage
I + II	123 (54.7)	102 (45.3)	0.015	38 (16.9)	187 (83.1)	0.743
III + IV	172 (44.2)	21 (55.8)		71 (18.3)	318 (81.7)
Vascular or neural invasion
Negative	168 (49.9)	169 (50.1)	0.331	60 (17.8)	277 (82.2)	0.831
Positive	127 (45.8)	150 (54.2)		47 (17.0)	230 (83.0)
Gastrectomy method
Promixal	41 (51.3)	39 (48.7)	0.742	15 (18.7)	65 (81.3)	0.598
Distal	143 (48.5)	152 (51.5)		55 (18.6)	240 (81.4)
Total	111 (46.4)	128 (53.6)		37 (15.5)	202 (84.5)
Resection margins
R0	215 (49.3)	221 (50.7)	0.329	77 (17.7)	359 (82.3)	0.907
R1	80 (44.9)	98 (55.1)		30 (16.9)	148 (83.1)
Intraoperative blood loss (mL)
≤ 200	273 (48.0)	296 (52.0)	0.906	101 (15.1)	468 (84.9)	0.545
> 200	22 (48.9)	23 (51.1)		6 (21.1)	39 (78.9)
Intraoperative blood transfusion
No	251 (46.7)	286 (53.3)	0.099	98 (18.2)	439 (81.8)	0.198
Yes	44 (57.1)	33 (42.9)		9 (11.7)	68 (88.3)
Preoperative WBC count (× 109/L)
< 5.6	-	-	-	64 (21.7)	231 (78.3)	0.008
≥ 5.6	-	-		43 (13.5)	276 (86.5)

P-leukopenia, defined as a preoperative WBC ≥ 4.0 × 10⁹/L and postoperative WBC < 4.0 × 10⁹/L, and an absolute decrease postoperatively of ≥ 0.5 × 10⁹/L. WBC: White blood cell count.

Table 4 Univariate and multivariate Cox regression analysis for gastric cancer-related survival

Factors	Univariate			Multivariate
	HR	95%CI	P value	HR	95%CI	P value
Age (yr)
≥ 58 vs < 58	1.036	0.811-1.324	0.776	-	-	-
Sex
Female vs male	1.033	0.794-1.345	0.809	-	-	-
Histology
Differentiated vs undifferentiated	1.661	1.115-2.475	< 0.001	1.261	0.839-1.896	0.265
Borrmann type
IV vs I/II/III	2.634	1.726-4.018	< 0.001	1.886	1.207-2.948	0.005
Tumor status
pT3 + pT4 vs pT1 + pT2	3.186	2.123-4.782	< 0.001	1.230	0.667-2.268	0.507
Lymph node metastasis
Yes vs no	3.098	2.128-4.512	< 0.001	1.485	0.871-2.533	0.147
pTNM stage
II vs I	2.713	1.318-5.583	0.007	1.813	0.756-4.350	0.183
III vs I	6.449	3.301-12.597	< 0.001	2.723	1.941-7.882	0.015
IV vs I	10.624	4.909-22.995	< 0.001	4.849	1.610-14.610	0.005
Vascular or neural invasion
Yes vs no	1.780	1.393-2.274	< 0.001	1.324	1.023-1.713	0.033
Operation method
Total gastrectomy vs Subtotal gastrectomy	1.425	1.113-1.824	0.005	1.198	0.931-1.542	0.159
Resection margins
R1 vs R0	2.081	1.624-2.667	< 0.001	1.904	1.298-2.792	0.001
Chemotherapy regimens
Triplet or doublet vs singlet or none	2.522	1.379-4.614	0.003	2.369	1.289-4.356	0.005
Intraoperative blood loss (mL)
> 200 vs ≤ 200	1.146	0.718-1.828	0.568	-	-	-
Intraoperative blood transfusion
Yes vs No	1.237	0.835-1.831	0.289	-	-	-
Preoperative WBC count (× 109/L)
≥ 5.6 vs < 5.6	1.542	1.204-1.975	0.001	1.553	1.205-2.001	0.001
P-leukopenia
Positive vs negtive	1.479	1.100-1.988	0.010	1.660	1.226-2.247	0.001

P-leukopenia, defined as a preoperative WBC ≥ 4.0 × 10⁹/L and postoperative WBC < 4.0 × 10⁹/L, and an absolute decrease postoperatively of ≥ 0.5 × 10⁹/L. CI: Confidence interval; HR: Hazard ratio; WBC: White blood cell count.