Table 1.

Selected candidate biomarkers for endometriosis chosen based on the quality of evidence, reproducibility, and to illustrate different potential types of biomarkers and samples.

Biomarker or combination of markers	Sample type	Diagnostic clinical relevance	Current gaps	References
Soluble BDNF	Plasma, serum	Minimal and mild EM, pain	Validation	33,39,40
lncRNA UCA1	Serum	Ovarian EM, disease stage	Function, validation	69
Annexin V+VEGF+CA-125+ I-CAM	Serum	EM	Validation	37,70
sVCAM-1/sICAM-1 ratio	Serum	EM	Validation	11
mtDNA deletions in EM	Blood	EM	Function, validation	9
miR-145+miR-923+miR141	Plasma	EM	Function, validation	71
mir122-5p	Serum	EM	Function, validation	52
miR-199-5p	Serum	EM	Function, validation	52
let7d	Serum	Severe EM, treatment of EM	Validation	72
KLK13	Cervicovaginal fluid	EM-associated infertility	Validation	65
sFLT-1	Urine	Minimal and mild EM	Validation	73
Leptin	Peritoneal fluid	Minimal and mild EM, pain	Validation	74
AOPP	Peritoneal fluid	EM, disease type (DIE, PE), disease stage	Validation	75
Nitrates/nitrites	Peritoneal fluid	EM, DIE, severe EM	Validation	75
miR-122+miR-145+miR-199a+miR-542-3p	Serum	EM	Function, validation	54

EM: endometriosis; DIE: deep infiltrating endometriosis; PE: peritoneal endometriosis.