Radical lymph node dissection and assessment: Impact on gallbladder cancer prognosis

Table 1 Number of radical resection procedures and their relationship with tumor node metastasis stages

TNM stage procedure	0	I	II	IIIA	IIIB	IVA	IVB	Sum
C + N	1	2	11		3			7
C + WR + N		2	4	6	5		2	19
C + S4aS5 + N				8	9		1	18
C + ELH + N							1	1
C + ERH + N						2		2
C + BD + N		12						1
C + WR + BD + N		1	3	1	3	1	1	10
C + S4As5 + BD + N				1	3	1	1	6
C + CH + BD + N						1		1
C + S4aS5 + other + N				3	1	1		5
C + S4As5 + BD + other + N						1		1
C + ERH + BD + other + N						1		1
HPD + N						2	4	6
Sum	1	6	8	19	24	10	10	78

¹Tumor of the patient infiltrated the serosa at the visceral surface of the gallbladder bottom;

²This patient was an incidental gallbladder cancer with a diagnosis confirmed during the initial operation by frozen section with a preoperative diagnosis of choledochal cyst. C: Cholecystectomy; N: Lymphadenectomy; WR: Wedge resection of the gallbladder fossae; S4aS5: Liver resection of segments IVa and V; ELH: Extended left hepatectomy; ERH: Extended right hepatectomy; CH: Central hepatectomy; BD: Resection of the bile duct; HPD: Hepatopancreaticoduodenectomy; Other: Other organ tissue resection; TNM: Tumor node metastasis.

Table 2 Topographical distribution of 465 lymph nodes evaluated in 78 patients with gallbladder cancer n (%)

Node group	Patients with node group	Lymph nodes evaluated	Patients with positive	Positive nodes
	evaluated		nodes
Cystic duct1	41 (53.95)	46 (9.89)	18 (23.08)	19 (19.39)
Pericholedochal1	68 (81.18)	146 (31.40)	20 (25.64)	29 (29.59)
Periportal1	47 (60.26)	74 (15.91)	12 (15.38)	18 (18.37)
Hepatic artery1	48 (61.54)	69 (14.84)	10 (12.82)	12 (12.24)
Posterosuperior pancreaticoduodenal2	22 (28.21)	56 (12.04)	6 (7.69)	12 (12.24)
Hilar1	18 (23.08)	26 (5.59)	4 (5.13)	6 (6.12)
Right celiac2	8 (10.26)	21 (4.52)	1 (1.28)	2 (2.04)
Perigastric2	4 (5.13)	6 (1.29)	0 (0.00)	0 (0.00)
Superior mesenteric artery2	6 (7.69)	11 (2.37)	0 (0.00)	0 (0.00)
Paraaortic2	6 (7.69)	10 (2.15)	0 (0.00)	0 (0.00)
Sum	78 (100)	465 (100)	37 (47.44)	98 (100)

¹First-station nodes;

²Second-station nodes; according to the American Joint Committee on Cancer cancer staging manual (7^th edition). Here, hilar lymph nodes classified as first-station nodes and perigastric lymph nodes classified as second-station nodes.

Table 3 Univariate analysis of clinical and histopathologic variables

Variable	Number of patients	Survival rate		P value
		3-yr	5-yr
Age (yr)				0.222
< 60	41	34.15%	17.07%
≥ 60	37	24.32%	18.92%
Sex				0.523
Female	46	28.26%	17.39%
Male	32	31.25%	18.75%
Cholelithiasis				0.374
Present	25	24.00%	16.00%
Absent	53	32.08%	18.87%
Type of radical resection				0.179
Extended cholecystectomy	7	42.86%	42.86%
Partial hepatectomy1	37	32.43%	13.51%
Partial hepatectomy and EBD resection	23	30.43%	26.09%
Extended hepatectomy2	5	0.00%	0.00%
Hepatopancreaticoduodenectomy	6	50.00%	33.33%
Hepatic infiltration				0.005
Present	41	14.63%	4.88%
Absent	37	51.35%	37.84%
Bile duct infiltration				0.238
Present	17	29.41%	23.53%
Absent	61	32.79%	19.67%
Venous invasion				0.001
Present	10	0.00%	0.00%
Absent	68	36.76%	23.53%
Perineural invasion				0.539
Present	9	22.22%	22.22%
Absent	69	33.33%	20.29%
Lymph node involvement				< 0.001
Present	37	16.22%	13.51%
Absent	41	46.34%	26.83%
pT classification3				0.001
pT0-pT2	20	60.00%	45.00%
pT3-pT4	58	22.41%	12.07%
pN classification3				< 0.001
pN0	41	46.34%	26.83%
pN1	31	16.13%	12.90%
pN2	6	16.67%	16.67%
pM classification3				0.002
pM0	74	33.78%	21.62%
pM1	4	0.00%	0.00%
TNM staging3				< 0.001
0-II	15	80.00%	60.00%
III	43	23.26%	11.63%
IV	20	15.00%	10.00%
TLNC				0.018
< 4	26	15.38%	7.69%
≥ 4	52	40.38%	26.92%
Number of positive lymph nodes				< 0.001
0	41	46.34%	26.83%
< 3	24	16.67%	16.67%
≥ 3	13	15.38%	7.69%
LNR				< 0.001
0	41	46.34%	26.83%
< 50	15	33.33%	33.33%
≥ 50	22	4.55%	0.00%
Histological type				0.706
Adenocarcinoma	69	33.33%	20.29%
Others	9	22.22%	22.22%
Histological grade				0.042
G1-G2	58	36.21%	24.14%
G3-G4	19	15.79%	5.26%

¹Includes wedge resection and resection of segments IVa and V;

²Includes extended right hepatectomy, extended left hepatectomy and central hepatectomy;

³According to the American Joint Committee on Cancer cancer staging manual (7^th edition). G1: Well differentiated; G2: Moderately differentiated; G3: Poorly differentiated; G4: Undifferentiated; EBD: Endoscopic balloon dilatation; TNM: Tumor node metastasis; TLNC: Total lymph node count; LNR: Lymph node ratio.

Table 4 Results of Cox multivariate regression analysis

Variable	Parameter estimate	Waldχ2	P	Hazard ratio	95%CI
Tumor node metastasis staging		20.559	< 0.001
0-II				1.000
III	-3.112	19.846	< 0.001	0.045	0.011-0.175
IV	-1.044	9.341	0.002	0.352	0.180-0.688
Lymph node ratio	2.424	20.247	< 0.001	11.293	3.929-32.465
Total lymph node count	-0.147	14.273	< 0.001	0.864	0.800-0.932
Histological grade	-0.755	5.512	0.019	0.470	0.250-0.883