Baseline clinicopathological characteristics Table 1 presents the baseline clinicopathological characteristics of the 122 patients who underwent RA for adrenal gland diseases. The mean age was 50.3 ± 13.7 (range, 19–74) years, and 72 patients (59%) were female. The mean BMI was 24.8 ± 4.2 (range, 17.2–44.3) kg/m2, and 52 (42.6%) patients were classified as overweight. The mean tumor size was 2.8 ± 1.5 (range, 0.8–10.1) cm. Most patients (113 patients, 92.6%) underwent LTA; and 9 (7.4%) patients underwent posterior retroperitoneoscopic adrenalectomy (PRA) 36 (29.5%) patients underwent right-side surgery, whereas 86 (70.5%) patients underwent left-side surgery. Adrenal tumor characteristics included incidentaloma, primary hyperaldosteronism, pheochromocytoma, and Cushing’s syndrome, with each accounting for 59.8%, 13.1%, 16.4%, and 10.7%, respectively.
Table 1
Baseline clinicopathologic characteristics of the study population
Total 122 patients
|
Age (years)
|
50.3 ± 13.7 (range, 19–74)
|
Gender
|
|
Male
|
50 (41.0%)
|
Female
|
72 (59.0%)
|
BMI (kg/m2)
|
24.8 ± 4.2 (range, 17.2–44.4)
|
Overweight
|
52 (42.6%)
|
Tumor size (cm)
|
2.8 ± 1.5 (range, 0.8–10.1)
|
Surgical approach
|
|
LTA
|
113 (92.6%)
|
PRA
|
9 (7.4%)
|
Operation side
|
|
Right
|
36 (29.5%)
|
Left
|
86 (70.5%)
|
Surgical period
|
|
2009 ~ 2018
|
63 (51.6%)
|
2019 ~ 2022
|
59 (48.4%)
|
Preoperative diagnosis
|
|
Incidentaloma
|
73 (59.8%)
|
Primary hyperaldosteronism
|
16 (13.1%)
|
Pheochromocytoma
|
20 (16.4%)
|
Cushing’s syndrome
|
13 (10.7%)
|
Data are expressed as the patient number (%) or mean ± SD. |
Abbreviations: BMI, body mass index; LTA, lateral transperitoneal adrenalectomy; PRA, posterior retroperitoneoscopic adrenalectomy |
Comparison of baseline clinicopathological characteristics according to sex, tumor size, and BMI Table 2 shows the baseline clinicopathological characteristics according to sex. The female group was significantly younger than the male group (47.7 ± 12.9 vs. 54.0 ± 13.9 years, P = 0.011). The mean operation time was significantly shorter for the female group than for the male group (137.4 ± 46.6 vs. 158.6 ± 49.5 min, P = 0.018). However, the BMI, mean tumor size, surgical approach, operative side, preoperative diagnosis, and postoperative VAS pain score did not significantly differ between the groups.
Table 2. Baseline clinicopathological characteristics according to gender
|
Male
(n = 50)
|
Female
(n = 72)
|
p-value
|
Age (years)
|
54.0 ± 13.9
|
47.7 ± 12.9
|
0.011
|
BMI (kg/m2)
|
25.2 ± 3.3
|
24.5 ± 4.7
|
0.375
|
Overweight
|
24 (48%)
|
28 (38.9%)
|
0.355
|
Operation time (min)
|
158.6 ± 49.5
|
137.4 ± 46.6
|
0.018
|
Tumor size (cm)
|
3.0 ± 1.8
|
2.7 ± 1.2
|
0.300
|
Surgical approach
|
|
|
0.485
|
LTA
|
45 (90%)
|
68 (94.4%)
|
|
PRA
|
5 (10%)
|
4 (5.6%)
|
|
Operation side
|
|
|
0.921
|
Right
|
15 (30%)
|
21 (29.2%)
|
|
Left
|
35 (70%)
|
51 (70.8%)
|
|
Surgical period
|
|
|
0.582
|
2009~2018
|
24 (48%)
|
39 (54.2%)
|
|
2019~2022
|
26 (52%)
|
33 (45.8%)
|
|
Preoperative diagnosis
|
|
|
0.577
|
Incidentaloma
|
28 (56%)
|
45 (62.5%)
|
|
Primary hyperaldosteronism
|
8 (16%)
|
8 (11.1%)
|
|
Pheochromocytoma
|
10 (20%)
|
10 (13.9%)
|
|
Cushing’s syndrome
|
4 (8%)
|
9 (12.5%)
|
|
Postoperative VAS
|
|
|
|
POD 0
|
5.0 ± 1.6
|
5.1 ± 1.8
|
0.743
|
POD 1
|
3.6 ± 1.1
|
3.4 ± 1.1
|
0.490
|
POD 2
|
3.2 ± 1.1
|
3.0 ± 0.9
|
0.430
|
POD 3
|
2.9 ± 0.9
|
2.7 ± 0.9
|
0.072
|
Data were expressed as number (%) or mean ± standard deviation.
A statistically significant difference was defined as p<0.05.
Abbreviations: BMI, body mass index; LTA, lateral transperitoneal adrenalectomy; PRA, posterior retroperitoneoscopic adrenalectomy; VAS, visual analog scale; POD, postoperative day
As shown in Table 3, the patients were divided into two groups according to tumor size: the small tumor group (< 3 cm, n = 74 [60.7%]) and large tumor group (≥ 3 cm, n = 48 [39.3%]). The mean operation time was significantly longer for the large-tumor group than for the small tumor group (160.3 ± 47.0 vs. 136.9 ± 47.9 min, P = 0.009). Pheochromocytoma in the large-tumor group and primary hyperaldosteronism in the small-tumor group were frequently diagnosed before surgery (P < 0.001). However, there were no statistically significant differences in age, sex, BMI, surgical approach, operative side, and postoperative VAS pain score.
Table 3. Baseline clinicopathological characteristics according to tumor size
|
Tumor size < 3cm (n = 74)
|
Tumor size ≥ 3cm (n = 48)
|
p-value
|
Age (years)
|
50.3 ± 11.8
|
50.2 ± 16.3
|
0.974
|
Gender
|
|
|
0.259
|
Male
|
27 (36.5%)
|
23 (47.9%)
|
|
Female
|
47 (63.5%)
|
25 (52.1%)
|
|
BMI (kg/m2)
|
24.9 ± 3.6
|
24.7 ± 4.9
|
0.856
|
Overweight
|
33 (44.6%)
|
19 (39.6%)
|
0.708
|
Operation time (min)
|
136.9 ± 47.9
|
160.3 ± 47.0
|
0.009
|
Surgical approach
|
|
|
0.701
|
LTA
|
68 (91.9%)
|
45 (93.8%)
|
|
PRA
|
6 (8.1%)
|
3 (6.2%)
|
|
Operation side
|
|
|
0.543
|
Right
|
20 (27.0%)
|
16 (33.3%)
|
|
Left
|
54 (73.0%)
|
32 (66.7%)
|
|
Surgical period
|
|
|
0.296
|
2009~2018
|
35 (47.3%)
|
28 (58.3%)
|
|
2019~2022
|
39 (52.7%)
|
20 (41.7%)
|
|
Preoperative diagnosis
|
|
|
<0.001
|
Incidentaloma
|
45 (60.8%)
|
28 (58.3%)
|
|
Primary hyperaldosteronism
|
16 (21.6%)
|
0 (0%)
|
|
Pheochromocytoma
|
4 (5.4%)
|
16 (33.3%)
|
|
Cushing’s syndrome
|
9 (12.2%)
|
4 (8.3%)
|
|
Postoperative VAS
|
|
|
|
POD 0
|
5.2 ± 1.6
|
4.9 ± 1.9
|
0.288
|
POD 1
|
3.5 ± 1.1
|
3.5 ± 1.1
|
0.846
|
POD 2
|
3.1 ± 0.9
|
3.1 ± 1.0
|
0.957
|
POD 3
|
2.8 ± 0.9
|
2.8 ± 0.9
|
0.751
|
Data were expressed as number (%) or mean ± standard deviation.
A statistically significant difference was defined as p<0.05.
Abbreviations: BMI, body mass index; LTA, lateral transperitoneal adrenalectomy; PRA, posterior retroperitoneoscopic adrenalectomy; VAS, visual analog scale; POD, postoperative day
The baseline clinicopathological characteristics according to BMI are presented in Table 4. The patients were divided into groups according to BMI: the normal group (≤ 25 kg/m2, n = 70 [57.4%]) and the overweight group (> 25 kg/m2, n = 52 [42.6%]). There were no statistically significant differences in any of the baseline clinicopathological characteristics between the two groups.
Table 4
Baseline clinicopathological characteristics according to BMI
|
BMI ≤ 25 kg/m2
(n = 70)
|
BMI > 25 kg/m2
(n = 52)
|
p-value
|
Age (years)
|
51.2 ± 14.0
|
49.1 ± 13.2
|
0.412
|
Gender
|
|
|
0.355
|
Male
|
26 (37.1%)
|
24 (46.2%)
|
|
Female
|
44 (62.9%)
|
28 (53.8%)
|
|
Tumor size (cm)
|
2.9 ± 1.7
|
2.7 ± 1.1
|
0.520
|
Operation time (min)
|
143.9 ± 51.9
|
149.1 ± 44.5
|
0.559
|
Surgical approach
|
|
|
0.909
|
LTA
|
65 (92.9%)
|
48 (92.3%)
|
|
PRA
|
5 (7.1%)
|
4 (7.7%)
|
|
Operation side
|
|
|
0.163
|
Right
|
17 (24.3%)
|
19 (36.5%)
|
|
Left
|
53 (75.7%)
|
33 (63.5%)
|
|
Surgical period
|
|
|
0.029
|
2009 ~ 2018
|
30 (42.9%)
|
33 (63.5%)
|
|
2019 ~ 2022
|
40 (57.1%)
|
19 (36.5%)
|
|
Preoperative diagnosis
|
|
|
0.450
|
Incidentaloma
|
40 (57.1%)
|
33 (63.5%)
|
|
Primary hyperaldosteronism
|
8 (11.4%)
|
8 (15.4%)
|
|
Pheochromocytoma
|
12 (17.1%)
|
8 (15.4%)
|
|
Cushing’s syndrome
|
10 (14.3%)
|
3 (5.8%)
|
|
Postoperative VAS
|
|
|
|
POD 0
|
5.0 ± 1.7
|
5.2 ± 1.8
|
0.618
|
POD 1
|
3.5 ± 1.1
|
3.5 ± 1.1
|
0.907
|
POD 2
|
3.2 ± 1.0
|
3.0 ± 0.9
|
0.239
|
POD 3
|
2.9 ± 0.9
|
2.7 ± 0.9
|
0.448
|
Data were expressed as number (%) or mean ± standard deviation. |
A statistically significant difference was defined as p < 0.05. |
Abbreviations: BMI, body mass index; LTA, lateral transperitoneal adrenalectomy; PRA, posterior retroperitoneoscopic adrenalectomy; VAS, visual analog scale; POD, postoperative day |
The results of the comparison of the baseline clinical characteristics according to the surgical period are summarized in Table 5. We divided the patients into two groups on the basis of the year 2019: the early group (to 2018, n = 63 [51.6%]) and late group (from 2019, n = 59 [48.4%]). The late group was significantly older than the early group (54.2 ± 12.9 vs. 46.6 ± 13.4 years, P = 0.002). The mean operation time was significantly shorter in the late group than in the early group (128.9 ± 37.7 vs. 162.1 ± 52.6 min, P < 0.001). Since 2019, both LTA and PRA have been performed at our institution (P < 0.001). Compared with the early group, the late group underwent significantly more operations for functional diseases than for incidentalomas (P < 0.001). However, there were no statistically significant differences in sex, BMI, tumor size, operative side, and postoperative VAS pain score.
Table 5. Baseline clinicopathological characteristics according to surgical period
|
To 2018
(n = 63)
|
From 2019
(n = 59)
|
p-value
|
Age (years)
|
46.6 ± 13.4
|
54.2 ± 12.9
|
0.002
|
Gender
|
|
|
0.582
|
Male
|
24 (38.1%)
|
26 (44.1%)
|
|
Female
|
39 (61.9%)
|
33 (55.9%)
|
|
BMI (kg/m2)
|
25.3 ± 4.0
|
24.4 ± 4.4
|
0.230
|
Overweight
|
33 (55.9%)
|
19 (32.2%)
|
|
Tumor size (cm)
|
2.9 ± 1.1
|
2.8 ± 1.8
|
0.694
|
Operation time (min)
|
162.1 ± 52.6
|
128.9 ± 37.7
|
<0.001
|
Surgical approach
|
|
|
0.001
|
LTA
|
63 (100%)
|
50 (84.7%)
|
|
PRA
|
0 (0%)
|
9 (15.3%)
|
|
Operation side
|
|
|
0.871
|
Right
|
19 (30.2%)
|
17 (28.8%)
|
|
Left
|
44 (69.8%)
|
42 (71.2%)
|
|
Preoperative diagnosis
|
|
|
<0.001
|
Incidentaloma
|
50 (79.4%)
|
23 (39.0%)
|
|
Primary hyperaldosteronism
|
1 (1.6%)
|
15 (25.4%)
|
|
Pheochromocytoma
|
12 (19.0%)
|
8 (13.6%)
|
|
Cushing’s syndrome
|
0 (0%)
|
13 (22.0%)
|
|
Postoperative VAS
|
|
|
|
POD 0
|
5.2 ± 1.6
|
4.9 ± 1.8
|
0.356
|
POD 1
|
3.5 ± 1.2
|
3.5 ± 1.0
|
0.879
|
POD 2
|
3.1 ± 1.0
|
3.1 ± 0.9
|
0.677
|
POD 3
|
2.8 ± 0.8
|
2.9 ± 1.0
|
0.604
|
Data were expressed as number (%) or mean ± standard deviation.
A statistically significant difference was defined as p<0.05.
Abbreviations: BMI, body mass index; LTA, lateral transperitoneal adrenalectomy; PRA, posterior retroperitoneoscopic adrenalectomy; VAS, visual analog scale; POD, postoperative day
Logistic regression analysis of risk factors associated with operation time We performed multivariate logistic regression analysis to validate the factors associated with operation time (Table 6). Univariate analysis identified tumor size, surgical period, primary hyperaldosteronism, and Cushing’s syndrome as significant risk factors for longer operation times. However, only pheochromocytoma was a significant independent risk factor for a longer operation time in the multivariate analysis (OR, 3.709; 95% CI, 1.127–12.205; P = 0.031).The operational time trend is shown in Fig. 1. The 122 lobectomy cases were divided into three groups, each comprising approximately 40 consecutive cases. The mean operation times for groups I, II, and III were 175.1 ± 54.1, 135.4 ± 37.8, and 128.7 ± 40.3 min, respectively. There was a statistically significant decrease in the mean operation time between groups I and II (P < 0.001) and between groups I and III (P < 0.001).
Table 6
Logistic regression analysis of risk factors associated with long operation time > 150 min
Variables
|
Simple Generalized Linear Model
|
Multiple Generalized Linear Model
|
OR
|
CI
|
p-Value
|
OR
|
CI
|
p-Value
|
Age
|
0.982
|
0.955–1.008
|
0.175
|
|
|
|
Sex
|
|
|
|
|
|
|
Female
|
ref.
|
|
|
|
|
|
Male
|
2.000
|
0.954–4.191
|
0.066
|
|
|
|
BMI(kg/m2)
|
|
|
|
|
|
|
Overweight
|
1.168
|
0.562–2.426
|
0.677
|
|
|
|
Tumor size (cm)
|
1.593
|
1.174–2.162
|
0.003
|
|
|
|
< 3cm
|
ref.
|
|
|
|
|
|
≥ 3cm
|
3.039
|
1.425–6.481
|
0.004
|
|
|
|
Surgical period
|
|
|
|
|
|
|
2009 ~ 2018
|
ref.
|
|
|
|
|
|
2019 ~ 2022
|
0.338
|
0.159–0.722
|
0.005
|
|
|
|
Preoperative diagnosis
|
|
|
|
|
|
|
Incidentaloma
|
ref.
|
|
|
ref.
|
|
|
Primary hyperaldosteronism
|
8.372
|
1.033–67.864
|
0.047
|
0.680
|
0.149 = 3.117
|
0.620
|
Pheochromocytoma
|
2.769
|
0.252–30.383
|
0.405
|
3.709
|
1.127–12.205
|
0.031
|
Cushing’s syndrome
|
36.000
|
3.692–351.002
|
0.002
|
0.202
|
0.022–1.834
|
0.155
|
Data are expressed as Odds ratio (OR) and 95% confidence interval (CI) |
A statistically significant difference was defined as p < 0.05. |
Abbreviations: BMI, body mass index |