Prognostic significance of regional lymphadenectomy in T1b gallbladder cancer: Results from 24 hospitals in China

Table 1 Characteristics of T1b gallbladder cancer patients who underwent cholecystectomy alone or cholecystectomy combined with regional lymphadenectomy

Characteristic	Ch, n = 44	Ch + RL, n = 77	P value
Age, mean ± SD in yr	62.8 ± 11.3	61.4 ± 9.4	0.48
Female	34 (77.3)	57 (74.3)	0.69
Admitted to high-volume centers1	22 (50.0)	46 (59.7)	0.30
Nodal metastasis			—3
Negative, N0	0 (0)	55 (71.4)	—
Positive, N+	1 (2.3)	7 (9.1)	—
Undetermined, Nx	43 (97.7)	15 (19.5)	—
No. of examined nodes, median (range)	0 (0-1)	3 (0-14)	—3
Malignancy diagnosed after primary surgery	25 (56.8)	15 (19.5)	< 0.001b
Hepatectomy	2 (4.5)2	54 (70.1)	< 0.001b
Liver wedge resection	2 (4.5)	51 (66.2)	—
Segment IVb + V resection	0 (0)	3 (3.9)	—
Bile duct resection	1 (2.3)	5 (6.5)	0.41
Negative resection margin	40 (90.9)	73 (94.8)	0.46
Poor histological grade	4 (9.1)	15 (19.5)	0.19
Microscopic vascular invasion	0 (0)	3 (3.9)	0.55
Perineural invasion	0 (0)	1 (1.3)	1.00

The data are presented as n (%) unless otherwise specified.

^bP < 0.01.

¹Hospitals admitting more than 20 gallbladder cancer patients per year.

²Combined liver wedge resection was performed in 2 patients who underwent cholecystectomy (Ch) because the tumor was on the liver bed.

³Nodal metastasis and number of examined nodes were different between the two groups because lymphadenectomy was not performed in the Ch group.

Ch: Cholecystectomy; Ch + RL: Cholecystectomy combined with regional lymphadenectomy; SD: Standard deviation.

Table 2 Association between surgery type and overall survival in T1b gallbladder cancer patients

Variable	Model 1	Model 2	Model 3
Ch + RL vs Ch	0.50 (0.26-0.97)a	0.47 (0.24-0.92)	0.51 (0.26-0.99)a
Age > 60-years-old	—	1.73 (0.82-3.64)	1.91 (0.89-4.10)
Female sex	—	0.68 (0.33-1.39)	0.60 (0.29-1.26)
High hospital volume	—	0.97 (0.50-1.89)	0.99 (0.50-1.95)
Negative margin	—	—	0.31 (0.11-0.83)b

^aP < 0.05.

^bP < 0.01.

Model 1: Crude model; Model 2: Adjusted for age (≥ 60 years vs < 60 years), sex, and hospital volume (high vs low); Model 3: Adjusted for age, sex, hospital volume, and resection margin (positive vs negative). Ch: Cholecystectomy; Ch + RL: Cholecystectomy combined with regional lymphadenectomy.