Nomogram using F-18 fluorodeoxyglucose positron emission tomography/computed tomography for preoperative prediction of lymph node metastasis in gastric cancer

Table 1 Patient characteristics

	Training cohort			Validation cohort
Variables	LN metastasis (-)	LN metastasis (+)	P value	LN metastasis (-)	LN metastasis (+)	P value
	(n = 206)	(n = 171)		(n = 128)	(n = 61)
Age	59.2 ± 11.5	59.6 ± 12.1	0.701	59.5 ± 12.1	61.8 ± 12.8	0.218
Sex			0.577			0.456
Male	122 (59.2%)	107 (62.6%)		73 (57.0%)	39 (63.9%)
Female	84 (40.8%)	64 (37.4%)		55 (43.0%)	22 (36.1%)
Tumor Location			< 0.001			0.034
Upper	46 (22.3%)	27 (15.8%)		25 (19.5%)	15 (24.6%)
Middle	32 (15.5%)	35 (20.5%)		24 (18.8%)	11 (18.0%)
Low	122 (59.2%)	81 (47.4%)		78 (60.9%)	30 (49.2%)
Mixed	6 (2.9%)	28 (16.4%)		1 ( 0.8%)	5 (8.2%)
Pathologic T stage			< 0.001			< 0.001
1	158 (76.7%)	28 (16.4%)		100 (78.1%)	10 (16.4%)
2	20 (9.7%)	27 (15.8%)		11 (8.6%)	12 (19.7%)
3	18 (8.7%)	27 (15.8%)		8 (6.2%)	18 (29.5%)
4	10 (4.9%)	89 (52.0%)		9 (7.0%)	21 (34.4%)
WBC counts (103 cells/μL)	6.4 ± 1.8	6.2 ± 1.7	0.283	6.2 ± 1.6	6.5 ± 1.8	0.295
Blood hemoglobin levels (g/dL)	12.5 ± 1.6	12.0 ± 1.8	0.004	13.3 ± 9.7	12.2 ± 2.1	0.211
Platelet counts (103 cells/μL)	267.2 ± 72.6	287.9 ± 91.0	0.017	267.3 ± 74.4	282.0 ± 67.3	0.192
Neutrophil counts (cells/μL)	3777.4 ± 1458.7	3810.9 ± 1333.2	0.818	3686.8 ± 1367.7	3902.9 ± 1405.2	0.315
Lymphocyte counts (cells/μL)	1860.3 ± 609.4	1661.1 ± 589.8	0.001	1835.0 ± 521.7	1855.1 ± 764.4	0.853
PLR	159.3 ± 72.8	196.4 ± 98.8	< 0.001	155.3 ± 60.3	184.8 ± 111.5	0.057
NLR	2.3 ± 1.4	2.5 ± 1.2	0.036	2.2 ± 1.2	2.6 ± 2.0	0.136
CEA (ng/mL)	4.8 ± 25.9	7.9 ± 27.9	0.268	2.6 ± 3.5	3.7 ± 6.1	0.195
CA 19-9 (U/mL)	18.1 ± 62.7	96.0 ± 364.9	0.006	10.0 ± 7.6	12.7 ± 8.6	0.029
Albumin (g/dL)	4.1 ± 0.3	3.9 ± 0.4	< 0.001	4.0 ± 0.3	3.9 ± 0.4	0.032
T_SUVmax	2.9 ± 4.4	6.1 ± 5.5	< 0.001	2.2 ± 3.7	6.9 ± 6.7	< 0.001
N_SUVmax	0.1 ± 0.9	1.8 ± 3.7	< 0.001	0.1 ± 0.5	1.7 ± 3.9	0.002

LN: Lymph node; WBC: White blood cell; PLR: Platelet to lymphocyte ratio; NLR: Neutrophil to lymphocyte ratio; CEA: Carcinoembryonic Antigen; CA 19-9: Carbohydrate antigen 19-9; SUVmax: Maximum standardized uptake value; T_SUVmax: SUVmax of primary tumor; N_SUVmax: SUVmax of LN.