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://www.wjon.org

Original Article

Volume 14, Number 6, December 2023, pages 505-517

Development and Validation of Nomograms Based on Nutritional Risk Index for Predicting Extracapsular Extension and Seminal Vesicle Invasion in Patients Undergoing Radical Prostatectomy

Figure 1. Nomograms for predicting ECE (a) and SVI (b). bGS: biopsy Gleason score; ECE: extracapsular extension; NRI: nutritional risk index; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; SVI: seminal vesicle invasion.

Figure 2. ROC curves for nomograms predicting ECE and SVI in the primary cohort (a) and validation cohort (b). Red curves for ECE; blue curves for SVI. AUC: area under curve; ECE: extracapsular extension; ROC: receiver operating characteristic; SVI: seminal vesicle invasion.

Figure 3. Calibration curves for nomograms predicting ECE and SVI in the primary cohort (a: ECE; b: SVI) and validation cohort (c: ECE; d: SVI). ECE: extracapsular extension; SVI: seminal vesicle invasion.

**Table 1.** Baseline Characteristics of the Separate Patient Cohorts
Characteristics	Primary cohort (n = 489)	Validation cohort (n = 245)	P value
BMI: body mass index; DRE: digital rectal examination; ECE: extracapsular extension; IQR: interquartile range; NRI: nutritional risk index; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; SVI: seminal vesicle invasion.
Age (years), median (IQR)	69.0 (64.0 - 74.0)	69.0 (65.0 - 75.5)	0.246
BMI (kg/m²), n (%)			0.030
< 25	252 (51.5%)	147 (60.0%)
≥ 25	237 (48.5%)	98 (40.0%)
NRI, n (%)			0.354
> 98	419 (85.7%)	216 (88.2%)
≤ 98	70 (14.3%)	29 (11.8%)
DRE, n (%)			0.387
Normal	388 (79.3%)	201 (82.0%)
Abnormal	101 (20.7%)	44 (18.0%)
PPC (%), median (IQR)	41.7 (23.1 - 66.7)	33.3 (21.4 - 58.3)	0.034
Biopsy Gleason score, n (%)			0.003
≤ 3+4	190 (38.9%)	123 (50.2%)
≥ 4+3	299 (61.1%)	122 (49.8%)
Preoperative PSA (ng/mL), n (%)			0.258
< 20	350 (71.6%)	185 (75.5%)
≥ 20	139 (28.4%)	60 (24.5%)
Prostate volume (mL), median (IQR)	35.6 (25.4 - 48.8)	34.8 (23.4 - 50.7)	0.674
PSAD, n (%)			0.879
≤ 0.15	82 (16.8%)	40 (16.3%)
> 0.15	407 (83.2%)	205 (83.7%)
ECE, n (%)			0.049
Absent	260 (53.2%)	149 (60.8%)
Present	229 (46.8%)	96 (39.2%)
SVI, n (%)			0.071
Absent	404 (82.6%)	215 (87.8%)
Present	85 (17.4%)	30 (12.2%)

Table 1. Baseline Characteristics of the Separate Patient Cohorts

Characteristics

Primary cohort (n = 489)

Validation cohort (n = 245)

P value

BMI: body mass index; DRE: digital rectal examination; ECE: extracapsular extension; IQR: interquartile range; NRI: nutritional risk index; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; SVI: seminal vesicle invasion.

Age (years), median (IQR)

69.0 (64.0 - 74.0)

69.0 (65.0 - 75.5)

0.246

BMI (kg/m²), n (%)

0.030

< 25

252 (51.5%)

147 (60.0%)

≥ 25

237 (48.5%)

98 (40.0%)

NRI, n (%)

0.354

> 98

419 (85.7%)

216 (88.2%)

≤ 98

70 (14.3%)

29 (11.8%)

DRE, n (%)

0.387

Normal

388 (79.3%)

201 (82.0%)

Abnormal

101 (20.7%)

44 (18.0%)

PPC (%), median (IQR)

41.7 (23.1 - 66.7)

33.3 (21.4 - 58.3)

0.034

Biopsy Gleason score, n (%)

0.003

≤ 3+4

190 (38.9%)

123 (50.2%)

≥ 4+3

299 (61.1%)

122 (49.8%)

Preoperative PSA (ng/mL), n (%)

0.258

< 20

350 (71.6%)

185 (75.5%)

≥ 20

139 (28.4%)

60 (24.5%)

Prostate volume (mL), median (IQR)

35.6 (25.4 - 48.8)

34.8 (23.4 - 50.7)

0.674

PSAD, n (%)

0.879

≤ 0.15

82 (16.8%)

40 (16.3%)

> 0.15

407 (83.2%)

205 (83.7%)

ECE, n (%)

0.049

Absent

260 (53.2%)

149 (60.8%)

Present

229 (46.8%)

96 (39.2%)

SVI, n (%)

0.071

Absent

404 (82.6%)

215 (87.8%)

Present

85 (17.4%)

30 (12.2%)

**Table 2.** Clinicopathologic Characteristics of Patients in Primary Cohort
Characteristics	Malnutrition (NRI ≤ 98, n = 70)	Normal nutrition (NRI > 98, n = 419)	P value
BMI: body mass index; DRE: digital rectal examination; ECE: extracapsular extension; IQR: interquartile range; NRI: nutritional risk index; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; SVI: seminal vesicle invasion.
Age (years), median (IQR)	70.5 (65.0 - 76.0)	69.0 (64.0 - 74.0)	0.030
BMI (kg/m²), n (%)			0.010
< 25	46 (65.7%)	206 (49.2%)
≥ 25	24 (34.3%)	213 (50.8%)
DRE, n (%)			0.642
Normal	57 (81.4%)	331 (79.0%)
Abnormal	13 (18.6%)	88 (21.0%)
PPC (%), median (IQR)	41.7 (16.7-73.3)	41.7 (24.1-66.7)	0.607
Biopsy Gleason score, n (%)			0.751
≤ 3+4	26 (37.1%)	164 (39.1%)
≥ 4+3	44 (62.9%)	255 (60.9%)
Preoperative PSA (ng/mL), n (%)			0.020
< 20	42 (60.0%)	308 (73.5%)
≥ 20	28 (40.0%)	111 (26.5%)
Prostate volume (mL), median (IQR)	37.3 (27.4 - 46.8)	35.1 (25.1 - 49.1)	0.606
PSAD, n (%)			0.196
≤ 0.15	8 (11.4%)	74 (17.7%)
> 0.15	62 (88.6%)	345 (82.3%)
ECE, n (%)			0.017
Absent	28 (40.0%)	232 (55.4%)
Present	42 (60.0%)	187 (44.6%)
SVI, n (%)			0.020
Absent	51 (72.9%)	353 (84.2%)
Present	19 (27.1%)	66 (15.8%)

Table 2. Clinicopathologic Characteristics of Patients in Primary Cohort

Characteristics

Malnutrition (NRI ≤ 98, n = 70)

Normal nutrition (NRI > 98, n = 419)

P value

Age (years), median (IQR)

70.5 (65.0 - 76.0)

69.0 (64.0 - 74.0)

0.030

BMI (kg/m²), n (%)

0.010

< 25

46 (65.7%)

206 (49.2%)

≥ 25

24 (34.3%)

213 (50.8%)

DRE, n (%)

0.642

Normal

57 (81.4%)

331 (79.0%)

Abnormal

13 (18.6%)

88 (21.0%)

PPC (%), median (IQR)

41.7 (16.7-73.3)

41.7 (24.1-66.7)

0.607

Biopsy Gleason score, n (%)

0.751

≤ 3+4

26 (37.1%)

164 (39.1%)

≥ 4+3

44 (62.9%)

255 (60.9%)

Preoperative PSA (ng/mL), n (%)

0.020

< 20

42 (60.0%)

308 (73.5%)

≥ 20

28 (40.0%)

111 (26.5%)

Prostate volume (mL), median (IQR)

37.3 (27.4 - 46.8)

35.1 (25.1 - 49.1)

0.606

PSAD, n (%)

0.196

≤ 0.15

8 (11.4%)

74 (17.7%)

> 0.15

62 (88.6%)

345 (82.3%)

ECE, n (%)

0.017

Absent

28 (40.0%)

232 (55.4%)

Present

42 (60.0%)

187 (44.6%)

SVI, n (%)

0.020

Absent

51 (72.9%)

353 (84.2%)

Present

19 (27.1%)

66 (15.8%)

**Table 3.** Univariate and Multivariate Analyses for ECE in Primary Cohort
Variables	Univariate analysis	Multivariate analysis
BMI: body mass index; CI: confidence interval; DRE: digital rectal examination; ECE: extracapsular extension; NRI: nutritional risk index; OR: odds ratio; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; Ref: reference.
Age (years)	0.992 (0.968 - 1.016)	0.503
BMI (kg/m²)
< 25	Ref
≥ 25	1.034 (0.725 - 1.475)	0.854
NRI
> 98	Ref		Ref
≤ 98	1.861 (1.111 - 3.116)	0.018	1.901 (1.050 - 3.440)	0.034
DRE
Normal	Ref
Abnormal	1.330 (0.858 - 2.062)	0.203
PPC (%)	1.026 (1.019 - 1.033)	< 0.001	1.016 (1.008 - 1.024)	< 0.001
Biopsy Gleason score
≤ 3+4	Ref		Ref
≥ 4+3	5.385 (3.574 - 8.114)	< 0.001	3.520 (2.263 - 5.475)	< 0.001
Preoperative PSA (ng/mL)
< 20	Ref		Ref
≥ 20	4.610 (2.993 - 7.099)	< 0.001	2.299 (1.406 - 3.758)	0.001
Prostate volume (mL)	0.996 (0.988 - 1.005)	0.384
PSAD
≤ 0.15	Ref		Ref
> 0.15	3.828 (2.191 - 6.687)	< 0.001	2.000 (1.077 - 3.713)	0.028

Table 3. Univariate and Multivariate Analyses for ECE in Primary Cohort

Variables

Univariate analysis

Multivariate analysis

OR (95% CI)

P value

OR (95% CI)

P value

BMI: body mass index; CI: confidence interval; DRE: digital rectal examination; ECE: extracapsular extension; NRI: nutritional risk index; OR: odds ratio; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; Ref: reference.

Age (years)

0.992 (0.968 - 1.016)

0.503

BMI (kg/m²)

< 25

Ref

≥ 25

1.034 (0.725 - 1.475)

0.854

NRI

> 98

Ref

≤ 98

1.861 (1.111 - 3.116)

0.018

1.901 (1.050 - 3.440)

0.034

DRE

Normal

Ref

Abnormal

1.330 (0.858 - 2.062)

0.203

PPC (%)

1.026 (1.019 - 1.033)

< 0.001

1.016 (1.008 - 1.024)

< 0.001

Biopsy Gleason score

≤ 3+4

Ref

≥ 4+3

5.385 (3.574 - 8.114)

< 0.001

3.520 (2.263 - 5.475)

< 0.001

Preoperative PSA (ng/mL)

< 20

Ref

≥ 20

4.610 (2.993 - 7.099)

< 0.001

2.299 (1.406 - 3.758)

0.001

Prostate volume (mL)

0.996 (0.988 - 1.005)

0.384

PSAD

≤ 0.15

Ref

> 0.15

3.828 (2.191 - 6.687)

< 0.001

2.000 (1.077 - 3.713)

0.028

**Table 4.** Univariate and Multivariate Analyses for SVI in Primary Cohort
Variables	Univariate analysis	Multivariate analysis
BMI: body mass index; CI: confidence interval; DRE: digital rectal examination; NRI: nutritional risk index; OR: odds ratio; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; Ref: reference; SVI: seminal vesicle invasion.
Age (years)	0.987 (0.956 - 1.018)	0.408
BMI (kg/m²)
< 25	Ref
≥ 25	0.742 (0.463 - 1.190)	0.216
NRI
> 98	Ref		Ref
≤ 98	1.993 (1.106 - 3.590)	0.022	2.255 (1.088 - 4.676)	0.029
DRE
Normal	Ref
Abnormal	0.718 (0.386 - 1.336)	0.296
PPC (%)	1.043 (1.033 - 1.053)	< 0.001	1.034 (1.023 - 1.045)	< 0.001
Biopsy Gleason score
≤ 3+4	Ref		Ref
≥ 4+3	17.278 (6.213 - 48.047)	< 0.001	8.626 (2.986 - 24.915)	< 0.001
Preoperative PSA (ng/mL)
< 20	Ref		Ref
≥ 20	4.749 (2.909 - 7.751)	< 0.001	1.628 (0.882 - 3.004)	0.119
Prostate volume (mL)	1.001 (0.990 - 1.012)	0.859
PSAD
≤ 0.15	Ref		Ref
≥ 0.15	3.051 (1.282 - 7.258)	0.012	1.072 (0.381 - 3.018)	0.895

Table 4. Univariate and Multivariate Analyses for SVI in Primary Cohort

Variables

Univariate analysis

Multivariate analysis

OR (95% CI)

P value

OR (95% CI)

P value

BMI: body mass index; CI: confidence interval; DRE: digital rectal examination; NRI: nutritional risk index; OR: odds ratio; PPC: percentage of positive biopsy cores; PSA: prostate-specific antigen; PSAD: prostate-specific antigen density; Ref: reference; SVI: seminal vesicle invasion.

Age (years)

0.987 (0.956 - 1.018)

0.408

BMI (kg/m²)

< 25

Ref

≥ 25

0.742 (0.463 - 1.190)

0.216

NRI

> 98

Ref

≤ 98

1.993 (1.106 - 3.590)

0.022

2.255 (1.088 - 4.676)

0.029

DRE

Normal

Ref

Abnormal

0.718 (0.386 - 1.336)

0.296

PPC (%)

1.043 (1.033 - 1.053)

< 0.001

1.034 (1.023 - 1.045)

< 0.001

Biopsy Gleason score

≤ 3+4

Ref

≥ 4+3

17.278 (6.213 - 48.047)

< 0.001

8.626 (2.986 - 24.915)

< 0.001

Preoperative PSA (ng/mL)

< 20

Ref

≥ 20

4.749 (2.909 - 7.751)

< 0.001

1.628 (0.882 - 3.004)

0.119

Prostate volume (mL)

1.001 (0.990 - 1.012)

0.859

PSAD

≤ 0.15

Ref

≥ 0.15

3.051 (1.282 - 7.258)

0.012

1.072 (0.381 - 3.018)

0.895