A preoperative predictive model for stage IV endometriosis

Figures & data

Figure 1. Flow chart of the patients included.

Table 1. Clinical characteristics of training and validation samples.

	Training sample n = 140	Validation sample n = 140	p Value
Age (mean ± SD)	33.8 ± 7.9	33.2 ± 6.8	0.496^a
Sterility [n (%)]	2 (1.4%)	7 (5%)	0.235^b
≤3 years	1 (0.7%)	3 (2.1%)
>3 years	1 (0.7%)	4 (2.9%)
Previous pregnancy [n (%)]	59 (42.1%)	61 (43.6%)	0.809^b
VAS score [n (%)]			0.089^b
0–3	92 (65.7%)	105 (75.0%)
4–10	48 (34.3%)	35 (25.0%)
Positive signs
Number of positive signs (mean ± SD)	1.1 ± 1.1	1.1 ± 0.8	0.949^a
Fixed uterine [n (%)]	34 (24.3%)	45 (32.1%)	0.144^b
Fixed ovarian cyst [n (%)]	92 (65.7%)	100 (71.4%)	0.303^b
Uterosacral ligament nodule with tenderness [n (%)]	16 (11.4%)	8 (5.7%)	0.088^b
Rectovaginal septum nodule with tenderness [n (%)]	7 (5.0%)	3 (2.1%)	0.335^b
CA125 (U/mL) (mean ± SD)	65.2 ± 106.6	94.0 ± 265.3	0.237^a
hsCRP (mg/L) (mean ± SD)	2.6 ± 12.0	1.5 ± 3.4	0.299^a
Bilateral EMS [n (%)]	27 (19.3%)	19 (13.6%)	0.197^b
Sum of sizes of EMS (cm) (mean ± SD)	6.1 ± 3.0	6.0 ± 3.1	0.554^a
Indication for surgery			0.060^b
Pain [n (%)]	56 (40.0%)	41 (29.3%)
Others [n (%)]	84 (60.0%)	99 (70.7%)
ASRM stage			0.632^b
Stage I-III [n (%)]	76 (54.3%)	72 (51.4%)
Stage IV [n (%)]	64 (45.7%)	68 (48.6%)
DIE [n (%)]	15 (10.7%)	8 (5.7%)	0.128^b

^at-test.

^bχ² test.

VAS: Visual Analogue Scale; CA125: carbohydrate antigen 125; hsCRP: hypersensitive C-reactive protein; EMS: endometriosis; ASRM: American Society for Reproductive Medicine; DIE: deep infiltrating endometriosis.

Table 2. Clinical characteristics of training samples.

	Stage I–III n = 76	Stage IV n = 64	p Value
Age (mean ± SD)	34.4 ± 8.5	33.2 ± 7.0	0.384^a
Sterility [n (%)]	1 (1.3%)	1 (1.6%)	0.362^b
Previous pregnancy [n (%)]	33 (43.4%)	26 (40.6%)	0.739^b
VAS score [n (%)]			0.000^b
0–3	62 (81.6%)	30 (46.9%)
4–10	14 (18.4%)	34 (53.1%)
Positive signs [n (%)]
Fixed uterine	10 (13.2%)	24 (37.5%)	0.001^b
Fixed ovarian cyst	39 (51.3%)	53 (82.8%)	0.000^b
Uterosacral ligament nodule with tenderness	1 (1.3%)	15 (23.4%)	0.000^b
Rectovaginal septum nodule with tenderness	0 (0)	7 (10.9%)	0.003^b
CA125 (U/mL) (mean ± SD)	49.2 ± 45.9	84.3 ± 147.9	0.072^a
hsCRP (mg/L) (mean ± SD)	1.7 ± 4.6	3.6 ± 17.0	0.359^a
Bilateral EMS, n (%)	5 (6.6%)	22 (34.4%)	0.000^b
Sum of sizes of EMS (cm) (mean ± SD)	5.4 ± 2.5	7.0 ± 3.3	0.002^a
Indication for surgery (pain or others [n (%)])			0.002^b
Pain	21 (27.6%)	35 (54.7%)
Others	55 (72.4%)	29 (45.3%)

^at-test.

^bχ² test.

VAS: Visual Analogue Scale; CA125: carbohydrate antigen 125; hsCRP: hypersensitive C-reactive protein; EMS: endometriosis.

Table 3. Multivariate logistic regression analysis of training sample.

Variable	β	Waldχ^2	p Value	OR (95% Cl)
VAS ≥ 4	1.349	10.066	0.002	3.855 [1.675–8.871]
Painful nodularity on uterosacral ligaments	2.636	5.882	0.015	13.954 [1.658–117.423]
Bilateral EMS	1.780	9.668	0.002	5.933 [1.931–18.225]

VAS: Visual Analogue Scale; EMS: endometriosis.

Figure 2. ROC curve to predict stage IV endometriosis in training sample (A) and validation sample (B).

Data availability statement

The datasets used and analysed during the current study are not publicly available due to the privacy protection of the subjects, but are available from the corresponding author on reasonable request.