Table 1 Univariate and multivariate analysis of predicting CSS and OS before IPTW-adjustment in NEEC patients

Age group (years)

 < 50

207

Reference

Reference

 50–65

3227

1.05 (0.83–1.32)

0.708

1.27 (1.0–1.61)

0.049

1.08 (0.86–1.35)

0.522

1.30 (1.04–1.63)

0.022

 > 65

4079

1.24 (0.99–1.57)

0.067

1.55 (1.22–1.96)

 < 0.001

1.40 (1.13–1.75)

0.003

1.71 (1.37–2.15)

 < 0.001

Year of diagnosis

 2004–2008

1151

Reference

Reference

 2009–2013

2039

0.86 (0.78–0.95)

0.003

0.882(0.80–0.98)

0.018

0.86 (0.79–0.95)

0.002

0.90 (0.82–0.98)

0.029

 2014–2018

4323

0.77 (0.70–0.85)

 < 0.001

0.76(0.68–0.85)

 < 0.001

0.77 (0.69–0.84)

 < 0.001

0.78 (0.70–0.86)

 < 0.001

Race recode

 Black

1616

Reference

Reference

 Others^a

725

0.71 (0.61–0.83)

 < 0.001

0.66 (0.56–0.77)

 < 0.001

0.74 (0.64–0.85)

 < 0.001

0.71 (0.61–0.81)

 < 0.001

 White

5172

0.84 (0.77–0.92)

 < 0.001

0.82 (0.75–0.90)

 < 0.001

0.85 (0.78–0.92)

 < 0.001

0.84 (0.77–0.91)

 < 0.001

Marital status

 Divorced/separated

956

Reference

Reference

 Married

3769

0.88 (0.79–0.99)

0.032

0.98 (0.87–1.09)

0.670

0.87 (0.78–0.96)

0.008

0.96 (0.86–1.07)

0.421

 Single/unmarried

1209

1.02 (0.89–1.17)

0.782

0.97 (0.85–1.11)

0.632

1.00 (0.88–1.14)

0.999

0.96 (0.85–1.09)

0.560

 Unknown

342

0.77 (0.62–0.95)

0.014

0.87 (0.69–1.08)

0.196

0.82 (0.67–0.99)

0.044

0.91 (0.75–1.11)

0.363

 Widowed

1237

1.13 (0.99–1.29)

0.076

1.05 (0.92–1.19)

0.507

1.22 (1.08–1.37)

0.002

1.10 (0.97–1.25)

0.123

Median household income

 < $50,000

894

Reference

Reference

 $50,000–65,000

2135

0.99 (0.88–1.13)

0.955

1.10 (0.97–1.24)

0.136

0.96 (0.86–1.08)

0.483

1.06 (0.94–1.18)

0.347

 > $65,000

4484

0.88 (0.78–0.98)

0.025

0.98 (0.87–1.10)

0.750

0.83 (0.75–0.92)

 < 0.001

0.93 (0.83–1.03)

0.158

Grade

 I

103

Reference

Reference

 II

278

1.15 (0.73–1.81)

0.545

1.12 (0.71–1.76)

0.634

1.06 (0.72–1.56)

0.766

1.05 (0.71–1.54)

0.814

 III

3523

1.65 (1.10–2.47)

0.015

1.42 (0.95–2.13)

0.090

1.33 (0.95–1.87)

0.101

1.18 (0.84–1.66)

0.340

 IV

1846

1.63 (1.08–2.44)

0.019

1.37(0.91–2.07)

0.128

1.33 (0.95–1.88)

0.099

1.17 (0.83–1.65)

0.386

 Unknown

1763

1.46 (0.97–2.20)

0.068

1.21 (0.81–1.83)

0.357

1.22 (0.86–1.72)

0.263

1.05 (0.74–1.48)

0.802

Histology

 Clear cell

977

Reference

Reference

 Serous

5577

1.23 (1.09–1.37)

 < 0.001

1.11 (0.98–1.25)

0.093

1.17 (1.06–1.30)

0.003

1.10 (0.99–1.22)

0.087

 Carcinosarcoma

959

1.99 (1.72–2.32)

 < 0.001

2.02 (1.72–2.38)

 < 0.001

1.90 (1.65–2.19)

 < 0.001

1.98 (1.70–2.30)

 < 0.001

TNM stage

 T1N0M0

2692

Reference

Reference

 T2N0M0

595

2.18 (1.82–2.61)

 < 0.001

2.06 (1.72–2.47)

 < 0.001

2.02 (1.72–2.36)

 < 0.001

1.92 (1.63–2.25)

 < 0.001

 T3-4aN0MO

919

3.58 (3.11–4.12)

 < 0.001

3.28 (2.84–3.80)

 < 0.001

3.02 (2.67–3.43)

 < 0.001

2.83 (2.49–3.23)

 < 0.001

 TanyN1M0

1372

4.04 (3.55–4.59)

 < 0.001

3.97 (3.46–4.56)

 < 0.001

3.48 (3.11–3.90)

 < 0.001

3.56 (3.15–4.03)

 < 0.001

 TanyN2M0

258

5.18 (4.12–6.51)

 < 0.001

4.84 (3.81–6.16)

 < 0.001

4.26 (3.40–5.26)

 < 0.001

4.08 (3.24–5.13)

 < 0.001

 TanyNanyM1

1677

9.95 (8.85–11.19)

 < 0.001

7.81 (6.83–8.92)

 < 0.001

8.07 (7.27–8.95)

 < 0.001

6.52(5.78–7.35)

 < 0.001

Surgery mode

 Total hysterectomy

6764

Reference

Reference

 Extendedl hysterectomy

749

1.50 (1.35–1.68)

 < 0.001

1.12 (1.00–1.25)

0.046

1.45 (1.31–1.61)

 < 0.001

1.10 (0.99–1.21)

0.086

Lymphadenectomy

 Yes

5449

Reference

Reference

 No

1658

2.30 (2.13–2.49)

 < 0.001

1.46 (1.33–1.59)

 < 0.001

2.23 (2.07–2.41)

 < 0.001

1.47 (1.35–1.60)

 < 0.001

 SLN biopsy/removed

406

0.89 (0.72–1.10)

0.285

1.03 (0.83–1.29)

0.762

0.88 (0.71–1.08)

0.205

1.01 (0.82–1.24)

0.931

Tumor Size (mm)

 < 20

905

Reference

Reference

 20–39

1639

1.38 (1.18–1.61)

 < 0.001

1.13 (0.97–1.32)

0.111

1.37 (1.19–1.58)

 < 0.001

1.15 (0.99–1.33)

0.057

 40–59

1494

1.82 (1.56–2.12)

 < 0.001

1.31 (1.12–1.53)

 < 0.001

1.76 (1.52–2.02)

 < 0.001

1.29 (1.11–1.48)

 < 0.001

 60–79

808

2.36(2.00–2.78)

 < 0.001

1.33 (1.12–1.57)

0.001

2.33 (1.99–2.71)

 < 0.001

1.35 (1.15–1.58)

 < 0.001

  ≥ 80

778

3.05 (2.59–3.59)

 < 0.001

1.46 (1.23–1.73)

 < 0.001

2.97 (2.55–3.46)

 < 0.001

1.49 (1.28–1.75)

 < 0.001

 Unknown

1889

1.88 (1.62–2.17)

 < 0.001

1.24(1.07–1.43)

0.005

1.85 (1.61–2.11)

 < 0.001

1.26 (1.10–1.45)

 < 0.001

Adjuvant therapy

 CRT

3171

Reference

Reference

 RT alone

795

0.94 (0.81–1.08)

0.381

1.12 (0.99–1.27)

0.066

1.61 (1.41–1.84)

 < 0.001

 CT alone

3547

1.93 (1.78–2.09)

 < 0.001

1.88 (1.74–2.02)

 < 0.001

1.26 (1.16–1.37)

 < 0.001

Subclassification of AT

 CT + EBRT

1236

Reference

Reference

 EBRT + VBT

153

0.64 (0.47–0.86)

0.004

0.99 (0.72–1.35)

0.947

0.74 (0.57–0.97)

0.027

1.08 (0.83–1.42)

0.564

 CT alone

3547

1.39 (1.26–1.54)

 < 0.001

1.15 (1.03–1.29)

0.010

1.38 (1.25–1.52)

 < 0.001

1.17 (1.06–1.30)

0.003

 EBRT alone

336

0.96 (0.79–1.16)

0.661

1.60 (1.31–1.96)

 < 0.001

1.13 (0.95–1.33)

0.168

1.77 (1.48–2.12)

 < 0.001

 VBT alone

306

0.43 (0.33–0.56)

 < 0.001

1.15 (0.87–1.52)

0.322

0.57(0.455–0.709)

 < 0.001

1.36 (1.08–1.72)

0.009

 CT + VBT

1403

0.46 (0.39–0.53)

 < 0.001

0.84 (0.72–0.98)

0.024

0.48 (0.42–0.55)

 < 0.001

0.84 (0.73–0.97)

0.018

 CT + EBRT + VBT

532

0.88 (0.74–1.05)

0.148

0.89(0.75–1.06)

0.184

0.89 (0.76–1.04)

0.152

0.90 (0.77–1.06)

0.202