High cyclin-dependent kinase 5 expression promotes tumor progression in gastric neuroendocrine carcinoma

Table 1 Patient characteristics of cyclin-dependent kinase 5 high and low groups, mean ± SD/n (%)

Variable	CDK5 high (n = 39)	CDK5 low (n = 26)	P value
Age, years			0.355
≤ 65	21 (53.8)	17 (65.4)
> 65	18 (46.2)	9 (34.6)
Sex			0.908
Female	10 (25.6)	7 (26.9)
Male	29 (74.4)	19 (70.1)
BMI, kg/m2	22.3 ± 2.4	21.8 ± 3.0	0.503
Tumor location			0.279
Upper	23 (59.0)	11 (42.3)
Middle	5 (12.8)	5 (19.2)
Lower	9 (23.1)	10 (38.5)
Mix	2 (5.1)	0 (0)
cT stage			0.002
T2	2 (5.1)	7 (26.9)
T3	10 (25.6)	12 (46.2)
T4	27 (69.3)	7 (26.9)
cN stage			0.032
N0	7 (17.9)	11 (42.3)
N+	32 (82.1)	15 (57.7)
Tumor resection			0.738
Total	27 (69.2)	19 (73.1)
Partial1	12 (30.8)	7 (26.9)
Tumor length, cm			< 0.001
< 5	8 (20.5)	18 (69.2)
≥ 5	31 (29.5)	8 (30.8)
Number of lymph nodes dissected	31.9 ± 11.9	34.4 ± 11.4	0.398
Metastatic lymph nodes	5.2 ± 5.2	2.8 ± 4.1	0.046
pT stage			0.001
pT1	1 (2.6)	3 (11.5)
pT2	1 (2.6)	9 (34.6)
pT3	15 (38.4)	8 (30.8)
pT4	22 (56.4)	6 (23.1)
pN stage			0.020
pN0	6 (15.4)	9 (34.6)
pN1	7 (17.9)	10 (38.5)
pN2	14 (35.9)	4 (15.4)
pN3	12 (30.8)	3 (11.5)
pTNM stage			< 0.001
I	2 (5.1)	5 (19.2)
II	8 (20.5)	15 (57.7)
III	29 (74.4)	6 (23.1)
Nerve invasion			0.139
Yes	33 (84.6)	18 (69.2)
No	6 (15.4)	8 (30.8)
Vascular invasion
Yes	20 (51.3)	17 (65.4)	0.261
No	19 (48.7)	9 (34.6)
Cell type
Large cell	27 (69.2)	22 (84.6)	0.158
Small cell	12 (30.8)	4 (15.4)

¹Distal or proximal gastrectomy.

BMI: Body mass index; pTNM: Pathological tumor-node-metastasis.

Table 2 Univariable and multivariable Cox regression analyses of risk factors for overall survival in patients with gastric neuroendocrine carcinoma

Clinicopathologic parameters	Univariate model		Multivariate model
	HR (95%CI)	P value	HR (95%CI)	P value
Age, years
≤ 65	Reference
> 65	0.97 (0.49-1.94)	0.939
Gender
Female	Reference
Male	0.91 (0.49-1.72)	0.778
Tumor location
Upper	Reference
Middle	0.39 (0.12-1.30)	0.126
Lower	0.87 (0.44-1.70)	0.680
Mix	1.13 (0.15-8.44)	0.902
Tumor resection
Total	Reference
Partial1	1.06 (0.55-2.04)	0.871
Tumor length, cm
< 5	Reference
≥ 5	2.42 (1.22-4.79)	0.011
pT stage
T1-T3	Reference		Reference
T4	2.29 (1.24-4.25)	0.008	1.64 (0.83-3.22)	0.154
pN stage
N0	Reference		Reference
N+	2.47 (1.09-5.60)	0.031	1.82 (0.76-4.36)	0.181
Nerve invasion
No	Reference
Yes	2.22 (0.98-5.01)	0.056
Vascular invasion
No	Reference
Yes	1.56 (0.77-3.17)	0.222
CDK5
Low	Reference		Reference
High	2.66 (1.33-5.32)	0.006	2.13 (1.03-4.41)	0.041

¹Distal or proximal gastrectomy.

CDK5: Cyclin-dependent kinase 5; HR: Hazard ratio; CI: Confidence interval.