Serum galectin-9 as a noninvasive biomarker for the detection of endometriosis and pelvic pain or infertility-related gynecologic disorders

Fertil Steril. 2017 Dec;108(6):1016-1025.e2. doi: 10.1016/j.fertnstert.2017.09.008.


Objective: To investigate the usefulness of soluble galectin-9 (Gal-9) in the noninvasive laboratory diagnosis of endometriosis and various gynecologic disorders.

Design: Prospective case-control study.

Setting: University medical centers.

Patient(s): A total of 135 women of reproductive age were involved in the study, 77 endometriosis patients, 28 gynecologic controls, and 30 healthy women.

Intervention(s): Diagnostic laparoscopy and collection of tissue biopsies, peritoneal cells, and native peripheral blood from different case groups of gynecology patients and healthy women.

Main outcome measure(s): The expression of mRNA and serum concentration of Gal-9.

Result(s): Semiquantitative reverse transcription-polymerase chain reaction analysis and serum soluble Gal-9 ELISA were performed on three different cohorts of patients: those with endometriosis, those with benign gynecologic disorders, and healthy controls. Differences in the Gal-9 concentrations between the investigated groups and the stability of Gal-9 in the serum and diagnostic characteristics of Gal-9 ELISA were determined by statistical evaluation and receiver operating characteristic (ROC) curve analysis. Significantly elevated Gal-9 levels were found in both minimal-mild (I-II) and moderate-severe (III-IV) stages of endometriosis in comparison with healthy controls. At a cutoff of 132 pg/mL, ROC analysis revealed an excellent diagnostic value of Gal-9 ELISA in endometriosis (area under the curve = 0.973) with a sensitivity of 94% and specificity of 93.75%, indicating better diagnostic potential than that of other endometriosis biomarkers. Furthermore, various pelvic pain or infertility-associated benign gynecologic conditions were also associated with increased serum Gal-9 levels.

Conclusion(s): Our results suggest that Gal-9 could be a promising noninvasive biomarker of endometriosis and a predictor of various infertility or pelvic pain-related gynecologic disorders.

Keywords: ELISA; Endometriosis; biomarker; galectin-9; serum.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Area Under Curve
  • Biomarkers / blood
  • Case-Control Studies
  • Endometriosis / blood*
  • Endometriosis / complications
  • Endometriosis / diagnosis
  • Endometriosis / genetics
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Galectins / blood*
  • Galectins / genetics
  • Humans
  • Infertility, Female / blood*
  • Infertility, Female / diagnosis
  • Infertility, Female / etiology
  • Infertility, Female / genetics
  • Middle Aged
  • Pelvic Pain / blood*
  • Pelvic Pain / diagnosis
  • Pelvic Pain / etiology
  • Pelvic Pain / genetics
  • Predictive Value of Tests
  • Prospective Studies
  • RNA, Messenger / genetics
  • ROC Curve
  • Reverse Transcriptase Polymerase Chain Reaction
  • Risk Factors
  • Severity of Illness Index
  • Up-Regulation


  • Biomarkers
  • Galectins
  • LGALS9 protein, human
  • RNA, Messenger