World J Oncol

World Journal of Oncology, ISSN 1920-4531 print, 1920-454X online, Open Access

Article copyright, the authors; Journal compilation copyright, World J Oncol and Elmer Press Inc

Journal website https://wjon.elmerpub.com

Original Article

Volume 000, Number 000, June 2026, pages 000-000

Experience of Robotic Partial Nephrectomy for Localized Renal Tumors: Functional and Oncologic Outcomes

↓ Figure 1. Renal function trajectory according to tumor size group after robot-assisted partial nephrectomy. Mean estimated glomerular filtration rate (eGFR) over time in patients undergoing robot-assisted partial nephrectomy, stratified by tumor size group: T1a (≤ 4 cm) and > 4 cm. Error bars indicate 95% confidence intervals. eGFR is expressed in mL/min/1.73 m². POD1: postoperative day 1.

↓ Figure 2. Forest plot of multivariable predictors of trifecta achievement. Forest plot showing odds ratios and 95% confidence intervals from the multivariable logistic regression model for predictors of trifecta achievement after robot-assisted partial nephrectomy. The model included tumor size group, RENAL complexity group, hilar anatomy complexity, and age. The dashed vertical line indicates an odds ratio of 1.0. Odds ratios are displayed on a logarithmic scale.

↓ **Table 1.** Baseline Patient and Tumor Characteristics According to Tumor Size Group
Variable	T1a (≤ 4 cm) (n = 42)	> 4 cm (n = 32)	P value
ASA: American Society of Anesthesiologists physical status classification; BMI: body mass index; CCI: Charlson Comorbidity Index; cT: clinical tumor stage; DM: diabetes mellitus; ECOG: Eastern Cooperative Oncology Group; GFR: glomerular filtration rate; HTN: hypertension; IQR: interquartile range; RENAL: Radius, Exophytic/endophytic properties, Nearness to the collecting system, Anterior/posterior location, and Location relative to polar lines.
Age (years), mean (SD)	52.86 (11.64)	57.19 (12.21)	0.116
Male patients, n (%)	25 (59.5%)	21 (65.6%)	0.769
BMI, mean (SD)	25.64 (3.97)	24.12 (3.90)	0.060
HTN, n (%)	22 (52.4%)	13 (40.6%)	0.442
DM, n (%)	7 (16.7%)	5 (15.6%)	1.000
ASA status, n (%)			0.455
1	3 (7.1%)	5 (15.6%)
2	27 (64.3%)	17 (53.1%)
3	12 (28.6%)	10 (31.2%)
ECOG performance status, n (%)			0.326
0	34 (81.0%)	23 (71.9%)
1	7 (16.7%)	9 (28.1%)
2	1 (2.4%)	0 (0.0%)
CCI age-adjusted, median (IQR)	3 (2–4)	4 (2–4)	0.113
Left-sided tumor, n (%)	22 (52.4%)	18 (56.2%)	0.924
cT, n (%)			< 0.001
cT1a	42 (100.0%)	0 (0.0%)
cT1b	0 (0.0%)	30 (93.8%)
cT2a	0 (0.0%)	2 (6.2%)
Tumor size (cm), median (IQR)	3.10 (2.78–3.50)	5.00 (4.50–6.00)	< 0.001
Hilar tumor, n (%)	3 (7.1%)	7 (21.9%)	0.090
RENAL score, median (IQR)	7 (5–8)	9 (8–10)	< 0.001
RENAL score category, n (%)			< 0.001
Low complexity (4–6)	17 (40.5%)	2 (6.2%)
Moderate complexity (7–9)	21 (50.0%)	18 (56.2%)
High complexity (10–12)	4 (9.5%)	12 (37.5%)
Complex hilar anatomy (> 1 renal vein or > 1 renal artery), n (%)	6 (14.3%)	6 (18.8%)	0.843
Preoperative hemoglobin (g/dL), mean (SD)	142.21 (14.97)	140.19 (16.83)	0.814
Preoperative GFR (mL/min/1.73 m²), mean (SD)	93.38 (15.60)	85.38 (19.84)	0.057

↓ Table 1. Baseline Patient and Tumor Characteristics According to Tumor Size Group

Variable

T1a (≤ 4 cm) (n = 42)

> 4 cm (n = 32)

P value

ASA: American Society of Anesthesiologists physical status classification; BMI: body mass index; CCI: Charlson Comorbidity Index; cT: clinical tumor stage; DM: diabetes mellitus; ECOG: Eastern Cooperative Oncology Group; GFR: glomerular filtration rate; HTN: hypertension; IQR: interquartile range; RENAL: Radius, Exophytic/endophytic properties, Nearness to the collecting system, Anterior/posterior location, and Location relative to polar lines.

Age (years), mean (SD)

52.86 (11.64)

57.19 (12.21)

0.116

Male patients, n (%)

25 (59.5%)

21 (65.6%)

0.769

BMI, mean (SD)

25.64 (3.97)

24.12 (3.90)

0.060

HTN, n (%)

22 (52.4%)

13 (40.6%)

0.442

DM, n (%)

7 (16.7%)

5 (15.6%)

1.000

ASA status, n (%)

0.455

3 (7.1%)

5 (15.6%)

27 (64.3%)

17 (53.1%)

12 (28.6%)

10 (31.2%)

ECOG performance status, n (%)

0.326

34 (81.0%)

23 (71.9%)

7 (16.7%)

9 (28.1%)

1 (2.4%)

0 (0.0%)

CCI age-adjusted, median (IQR)

3 (2–4)

4 (2–4)

0.113

Left-sided tumor, n (%)

22 (52.4%)

18 (56.2%)

0.924

cT, n (%)

< 0.001

cT1a

42 (100.0%)

0 (0.0%)

cT1b

0 (0.0%)

30 (93.8%)

cT2a

0 (0.0%)

2 (6.2%)

Tumor size (cm), median (IQR)

3.10 (2.78–3.50)

5.00 (4.50–6.00)

< 0.001

Hilar tumor, n (%)

3 (7.1%)

7 (21.9%)

0.090

RENAL score, median (IQR)

7 (5–8)

9 (8–10)

< 0.001

RENAL score category, n (%)

< 0.001

Low complexity (4–6)

17 (40.5%)

2 (6.2%)

Moderate complexity (7–9)

21 (50.0%)

18 (56.2%)

High complexity (10–12)

4 (9.5%)

12 (37.5%)

Complex hilar anatomy (> 1 renal vein or > 1 renal artery), n (%)

6 (14.3%)

6 (18.8%)

0.843

Preoperative hemoglobin (g/dL), mean (SD)

142.21 (14.97)

140.19 (16.83)

0.814

Preoperative GFR (mL/min/1.73 m²), mean (SD)

93.38 (15.60)

85.38 (19.84)

0.057

↓ **Table 2.** Perioperative and Postoperative Outcomes According to Tumor Size Group
Variable	T1a (≤ 4 cm) (n = 42)	> 4 cm (n = 32)	P value
*Significant difference. EBL: estimated blood loss; IQR: interquartile range; SD: standard deviation; WIT: warm ischemia time.
Postoperative hemoglobin (g/L), mean (SD)	126 (15.2)	119.7 (16.4)	0.153
Operation time (min), mean (SD)	226.33 (55.21)	252.06 (39.16)	0.030*
Console time (min), mean (SD)	164.18 (41.19)	170.50 (52.26)	0.564
WIT (min), mean (SD)	27.00 (9.43)	27.44 (9.73)	0.611
WIT ≤ 25 min, n (%)	21 (50.0%)	15 (46.9%)	0.975
EBL (mL), mean (SD)	80.4 (75.9)	73.6 (44)	0.499
Transfusion required, n (%)	0 (0.0%)	2 (6.2%)	0.184
Conversion to open surgery, n (%)	0 (0.0%)	0 (0.0%)	1.000
Conversion to radical nephrectomy, n (%)	0 (0.0%)	0 (0.0%)	1.000
Hemoglobin drop (g/L), mean (SD)	16.7 (9)	20.5 (9.9)	0.065
Pain score (0–10), median (IQR)	4.00 (3.00–4.00)	3.50 (3.00–5.00)	0.853
Opioid use, n (%)	16 (38.1%)	18 (56.2%)	0.188
Hospital stay (days), median (IQR)	5.00 (4.00–6.00)	6.00 (5.00–7.00)	0.040*
Positive surgical margin, n (%)	1 (2.4%)	0 (0.0%)	1.000
Postoperative complications, n (%)	3 (7.1%)	6 (18.8%)	0.163
Major postoperative complication (Clavien–Dindo ≥ 3), n (%)	0 (0.0%)	1 (3.1%)	0.432
Trifecta achieved, n (%)	21 (50.0%)	14 (43.8%)	0.765

↓ Table 2. Perioperative and Postoperative Outcomes According to Tumor Size Group

Variable

T1a (≤ 4 cm) (n = 42)

> 4 cm (n = 32)

P value

*Significant difference. EBL: estimated blood loss; IQR: interquartile range; SD: standard deviation; WIT: warm ischemia time.

Postoperative hemoglobin (g/L), mean (SD)

126 (15.2)

119.7 (16.4)

0.153

Operation time (min), mean (SD)

226.33 (55.21)

252.06 (39.16)

0.030*

Console time (min), mean (SD)

164.18 (41.19)

170.50 (52.26)

0.564

WIT (min), mean (SD)

27.00 (9.43)

27.44 (9.73)

0.611

WIT ≤ 25 min, n (%)

21 (50.0%)

15 (46.9%)

0.975

EBL (mL), mean (SD)

80.4 (75.9)

73.6 (44)

0.499

Transfusion required, n (%)

0 (0.0%)

2 (6.2%)

0.184

Conversion to open surgery, n (%)

0 (0.0%)

1.000

Conversion to radical nephrectomy, n (%)

0 (0.0%)

1.000

Hemoglobin drop (g/L), mean (SD)

16.7 (9)

20.5 (9.9)

0.065

Pain score (0–10), median (IQR)

4.00 (3.00–4.00)

3.50 (3.00–5.00)

0.853

Opioid use, n (%)

16 (38.1%)

18 (56.2%)

0.188

Hospital stay (days), median (IQR)

5.00 (4.00–6.00)

6.00 (5.00–7.00)

0.040*

Positive surgical margin, n (%)

1 (2.4%)

0 (0.0%)

1.000

Postoperative complications, n (%)

3 (7.1%)

6 (18.8%)

0.163

Major postoperative complication (Clavien–Dindo ≥ 3), n (%)

0 (0.0%)

1 (3.1%)

0.432

Trifecta achieved, n (%)

21 (50.0%)

14 (43.8%)

0.765

↓ **Table 3.** Renal Functional and Oncologic Follow-Up Outcomes According to Tumor Size Group
Variable	T1a (≤ 4 cm) (n = 42)	> 4 cm (n = 32)	P value
*Significant difference. CKD: chronic kidney disease; eGFR: estimated glomerular filtration rate; IQR: interquartile range; POD1: postoperative day 1; SD: standard deviation.
POD1 GFR (mL/min/1.73 m²), mean (SD)	75.37 (20.43)	71.73 (20.10)	0.468
3-month GFR (mL/min/1.73 m²), mean (SD)	86.65 (20.61)	76.57 (19.36)	0.034*
6-month GFR (mL/min/1.73 m²), mean (SD)	85.35 (20.21)	76.14 (19.37)	0.033*
12-month GFR (mL/min/1.73 m²), mean (SD)	86.46 (20.11)	75.18 (21.36)	0.012*
eGFR preservation at 3 months (%), mean (SD)	93.07 (18.34)	91.32 (17.82)	0.600
eGFR preservation at 6 months (%), mean (SD)	91.69 (18.04)	91.32 (19.89)	0.836
eGFR preservation at 12 months (%), mean (SD)	92.68 (17.47)	88.15 (16.45)	0.280
CKD upstage at 12 months, n (%)	9 (21.4%)	11 (34.4%)	0.328
Pathology, n (%)			0.321
Clear cell RCC	28 (66.7%)	19 (59.4%)
Papillary RCC	4 (9.5%)	8 (25.0%)
Other pathology	10 (23.8%)	5 (15.6%)
Follow-up time (months), median (IQR)	41.5 (18.3–64.8)	52.5 (19.5–77)	0.781
Recurrence, n (%)	0 (0.0%)	1 (3.1%)	0.432

↓ Table 3. Renal Functional and Oncologic Follow-Up Outcomes According to Tumor Size Group

Variable

T1a (≤ 4 cm) (n = 42)

> 4 cm (n = 32)

P value

*Significant difference. CKD: chronic kidney disease; eGFR: estimated glomerular filtration rate; IQR: interquartile range; POD1: postoperative day 1; SD: standard deviation.

POD1 GFR (mL/min/1.73 m²), mean (SD)

75.37 (20.43)

71.73 (20.10)

0.468

3-month GFR (mL/min/1.73 m²), mean (SD)

86.65 (20.61)

76.57 (19.36)

0.034*

6-month GFR (mL/min/1.73 m²), mean (SD)

85.35 (20.21)

76.14 (19.37)

0.033*

12-month GFR (mL/min/1.73 m²), mean (SD)

86.46 (20.11)

75.18 (21.36)

0.012*

eGFR preservation at 3 months (%), mean (SD)

93.07 (18.34)

91.32 (17.82)

0.600

eGFR preservation at 6 months (%), mean (SD)

91.69 (18.04)

91.32 (19.89)

0.836

eGFR preservation at 12 months (%), mean (SD)

92.68 (17.47)

88.15 (16.45)

0.280

CKD upstage at 12 months, n (%)

9 (21.4%)

11 (34.4%)

0.328

Pathology, n (%)

0.321

Clear cell RCC

28 (66.7%)

19 (59.4%)

Papillary RCC

4 (9.5%)

8 (25.0%)

Other pathology

10 (23.8%)

5 (15.6%)

Follow-up time (months), median (IQR)

41.5 (18.3–64.8)

52.5 (19.5–77)

0.781

Recurrence, n (%)

0 (0.0%)

1 (3.1%)

0.432

↓ **Table 4.** Univariable and Multivariable Logistic Regression Analyses for Predictors of Trifecta Achievement
Variable	Univariable OR (95% CI)	Univariable P	Multivariable OR (95% CI)	Multivariable P
The multivariable model was intentionally kept parsimonious because of the small sample size. On multivariable logistic regression analysis, predictors of trifecta achievement included tumor size > 4 cm (OR = 0.80, 95% CI 0.28–2.26, P = 0.673); high RENAL complexity (OR = 0.49, 95% CI 0.12–1.76, P = 0.286); complex hilar anatomy (OR = 2.32, 95% CI 0.62–9.99, P = 0.225); older age (OR = 1.03, 95% CI 0.99–1.07, P = 0.221). CI: confidence interval; OR: odds ratio.
Tumor > 4 cm (ref: T1a ≤ 4 cm)	0.78 (0.31–1.96)	0.594	0.80 (0.28–2.26)	0.673
High RENAL complexity (ref: low–moderate)	0.42 (0.12–1.32)	0.153	0.49 (0.12–1.76)	0.286
Complex hilar anatomy (ref: simple)	2.59 (0.74–10.56)	0.151	2.32 (0.62–9.99)	0.225
Age (per year)	1.02 (0.98–1.06)	0.337	1.03 (0.99–1.07)	0.221

↓ Table 4. Univariable and Multivariable Logistic Regression Analyses for Predictors of Trifecta Achievement

Variable

Univariable OR (95% CI)

Univariable P

Multivariable OR (95% CI)

Multivariable P

The multivariable model was intentionally kept parsimonious because of the small sample size. On multivariable logistic regression analysis, predictors of trifecta achievement included tumor size > 4 cm (OR = 0.80, 95% CI 0.28–2.26, P = 0.673); high RENAL complexity (OR = 0.49, 95% CI 0.12–1.76, P = 0.286); complex hilar anatomy (OR = 2.32, 95% CI 0.62–9.99, P = 0.225); older age (OR = 1.03, 95% CI 0.99–1.07, P = 0.221). CI: confidence interval; OR: odds ratio.

Tumor > 4 cm (ref: T1a ≤ 4 cm)

0.78 (0.31–1.96)

0.594

0.80 (0.28–2.26)

0.673

High RENAL complexity (ref: low–moderate)

0.42 (0.12–1.32)

0.153

0.49 (0.12–1.76)

0.286

Complex hilar anatomy (ref: simple)

2.59 (0.74–10.56)

0.151

2.32 (0.62–9.99)

0.225

Age (per year)

1.02 (0.98–1.06)

0.337

1.03 (0.99–1.07)

0.221