Prognostic importance of lymph node yield after curative resection of gastroenteropancreatic neuroendocrine tumours

Table 1 Characteristics of patients who had curative resection of gastroenteropancreatic neuroendocrine tumours

Variable		n (%)
Gender	Male	111 (51)
	Female	106 (49)
Age, yr	Median age	59
ECOG PS	PS 0	140 (65)
	PS 1	64 (30)
	PS 2	8(3.7)
	PS 3	5 (2.3)
Localisation	Small bowel	92 (42)
	Pancreas	55 (25)
	Appendix	39 (18)
	Rectum	15 (7)
	Colon	7 (3)
	Stomach	5 (2)
	Other	4 (2)
Grading	Grade 1	168 (77)
	Grade 2	49 (23)
Surgical margin	R0 resection	186 (86)
	R1 resection	30 (13)
	NA	1 (0.5)
Vascular infiltration	Present	89 (41)
	Absent	109 (51)
	NA	19 (8)
Perineal infiltration	Present	64 (29)
	Absent	133 (62)
	NA	20 (9.3)
Tumour necrosis	Present	10 (5)
	Absent	183 (86)
	NA	24 (10)
Lymph nodes retrieved	≥ 8	106 (49)
	< 8	45 (21)
	NA	66 (31)
Lymph node involvement	Positive	114 (52)
	Negative	37 (17)
Serum CgA Level	≥ ULN	46(21)
	Normal	69 (32)
	NA	102 (47)
Serum 5-HIAA	≥ ULN	17 (8)
	Negative	96 (44)
	NA	104 (48)

ECOG PS: Eastern Co-operative Oncology Group performance status; CgA: Chromogranin A; 5-HIAA: 5-hydroxyindoleacetic acid; ULN: Upper limit of normal; NA: Not available.

Table 2 Univariate analysis of variables for relapse-free survival and overall survival in patients who had curative resection of gastroenteropancreatic neuroendocrine tumours

Variable	LR P value	LR P value OS
Production of gut hormones	0.012	0.75
Production of CgA	0.09	0.81
Production of 5 HIAA	0.83	0.098
Genetic predisposition	0.011	0.71
Multiple NET	0.59	0.25
Other active malignancy	0.27	0.96
Vascular infiltration	0.17	0.97
Perineural infiltration	0.0023	0.016
Tumour necrosis	0.66	0.021
≥ 8 lymph nodes retrieved	0.047	0.94
Any lymph nodes positive	0.033	0.78
Gender	0.58	0.87
Localisation	0.0049	0.44
T stage	0.015	0.22
N stage	0.008	0.58
M stage	0.089	0.17
Grade	0.039	1
Surgical margin	0.32	0.69
ECOG performance status	0.75	< 0.0001
ACE comorbidity score	0.39	0.044
Localisation	0.63	0.61
Involved groups	0.062	0.09
TNM stage	0.019	0.19

NET: Neuroendocrine tumours; ECOG: Eastern Cooperative Oncology Group; ACE: Adult Comorbidity Evaluation; CgA: Chromogranin A.

Table 3 Multivariable analysis of variables associated with relapse-free survival in patients who had curative resection of gastroenteropancreatic neuroendocrine tumours

Variable	HR	95%CI	P value
Presence of perineural infiltration: Yes	1.57	0.81-3.06	0.1858
Over 8 lymph nodes retrieved: Yes	2.65	1.06-6.62	0.0365
Any lymph nodes found positive: Yes	2.62	0.88-7.78	0.0840
Localisation category: Pancreas (relative to “others”)	10.69	1.95-58.56	0.0063
Localisation category: Small bowel (relative to “others”)	12.17	2.19-67.69	0.0043

HR: Hazard ratio; CI: Confidence interval.