Diagnostic accuracy of Cancer Antigen 125 (CA125) for endometriosis in symptomatic women: A multi-center study

Martin Hirsch, James M N Duffy, James MN Duffy, Deguara CS, Christine S. Deguara, Colin J. Davis, Davis CJ, Khalid S. Khan
European journal of obstetrics, gynecology, and reproductive biology · 2016 · vol. 210 , pp. 102–107 · doi:10.1016/j.ejogrb.2016.12.002 · PMID:27987404 · W2559764858
article OA: green CC0 ⤵ 53 in-corpus citations
🔓 Open OA copy Full text JSON View on OpenAlex View on PubMed View at publisher
⚙ AI-generated summary by gemini-2.5-flash-lite+body, 2026-06-14 ⓘ

This study found that a CA125 level ≥ 30 u/ml had 96% specificity and 57% sensitivity for diagnosing endometriosis in symptomatic women.

One-sentence paraphrase of the abstract; not a substitute for reading it. No clinical advice. How this works

⚙ AI-generated deep summary by claude@2026-06, 2026-06-06 · read from full text ⓘ

This multi-center prospective observational cohort study evaluated the diagnostic accuracy of serum CA-125 (≥30 u/ml) for diagnosing histologically confirmed endometriosis in 58 consecutive symptomatic women undergoing elective diagnostic laparoscopy at two tertiary referral hospitals, excluding those suspected of other gynecologic pathology. Women with endometriosis had higher CA-125 levels than those without (mean 54.7 vs 16.2), with CA-125 ≥30 u/ml showing 96% specificity and 57% sensitivity; the positive likelihood ratio was 15.8 and the area under the ROC curve was 0.85. The authors note that while CA-125 ≥30 u/ml is highly predictive (a rule-in test), CA-125 <30 u/ml cannot rule out endometriosis due to limited sensitivity. This paper is centrally about endometriosis — it assesses CA-125 as a diagnostic rule-in versus rule-out marker in symptomatic women.

Read from the paper's body, not the abstract. Not a substitute for reading the paper. No clinical advice. How this works

Abstract

Study objectiveTo assess the diagnostic accuracy of serum Cancer Antigen 125 (CA 125)≥30units/milliliter (u/ml) for diagnosing endometriosis in symptomatic women.Study designProspective observational cohort study including patients with symptoms of pelvic pain or subfertility undergoing elective diagnostic laparoscopy at two tertiary referral hospitals. We excluded patients suspected to have other gynecological pathology. We evaluated the accuracy of serum CA 125 (index test) with histologically confirmed endometriosis (reference standard).Main resultsFifty-eight consecutive women recruited between October 2013 to March 2015. Women with endometriosis had a higher CA 125 level than those without endometriosis (mean 54.7+/-71.6 vs 16.2+/- 8.0). The specificity of CA 125≥30u/ml was 96% (95% CI 81.7-99.9%) and sensitivity was 57% (95% CI 37.4-74.5%). The positive likelihood ratio for the histological presence of endometriosis with a CA 125≥30u/ml was 15.8 (95% CI 2.3-112) providing a post-test probability of 94% (95% CI 71%-99%) in women with pelvic pain or subfertility. The area under the curve, 0.85 (95% CI 0.74-0.96) indicates high test accuracy.ConclusionsCA 125≥30u/ml is highly predictive of endometriosis in women with symptoms of pain and/or subfertility. CA 125 should be considered as a rule-in test for expediting the diagnosis and management of endometriosis, CA 125 <30u/ml is, however, unable to rule out endometriosis.
Full text 2,686 characters · extracted from oa-html · click to expand
Journal article Diagnostic accuracy of Cancer Antigen 125 (CA125) for endometriosis in symptomatic women: a multi-center study - Abstract: - Study Objective: To assess the diagnostic accuracy of serum Cancer Antigen 125 (CA 125) ≥ 30 units/milliliter (u/ml) for diagnosing endometriosis in symptomatic women. Study Design: Prospective observational cohort study including patients with symptoms of pelvic pain or subfertility undergoing elective diagnostic laparoscopy at two tertiary referral hospitals. We excluded patients suspected to have other gynecological pathology. We evaluated the accuracy of serum CA 125 (index test) with histologically confirmed endometriosis (reference standard). Main Results: Fifty-eight consecutive women recruited between October 2013 to March 2015. Women with endometriosis had a higher CA 125 level than those without endometriosis (mean 54.7 +/−71.6 vs 16.2 +/− 8.0). The specificity of CA 125 ≥ 30 u/ml was 96% (95% CI 81.7–99.9%) and sensitivity was 57% (95% CI 37.4–74.5%). The positive likelihood ratio for the histological presence of endometriosis with a CA 125 ≥ 30 u/ml was 15.8 (95% CI 2.3-112) providing a post-test probability of 94% (95% CI 71% − 99%) in women with pelvic pain or subfertility. The area under the curve, 0.85 (95% CI 0.74–0.96) indicates high test accuracy. Conclusions: CA 125 ≥ 30 u/ml is highly predictive of endometriosis in women with symptoms of pain and/or subfertility. CA 125 should be considered as a rule-in test for expediting the diagnosis and management of endometriosis, CA 125 < 30 u/ml is, however, unable to rule out endometriosis. - Publication status: - Published - Peer review status: - Peer reviewed Actions Access Document - Files: - - (Preview, Accepted manuscript, pdf, 212.6KB, Terms of use) - - Publisher copy: - 10.1016/j.ejogrb.2016.12.002 Authors - Publisher: - Elsevier - Journal: - European Journal of Obstetrics & Gynecology and Reproductive Biology More from this journal - Volume: - 210 - Pages: - 102-107 - Publication date: - 2016-12-05 - Acceptance date: - 2016-12-03 - DOI: - ISSN: - 0301-2115 - Keywords: - Pubs id: - pubs:664098 - UUID: - uuid:146c195b-4e92-436e-b7b5-6c2e438943b5 - Local pid: - pubs:664098 - Source identifiers: - 664098 - Deposit date: - 2016-12-07 - ARK identifier: Terms of use - Copyright holder: - © 2016 Elsevier Ireland Ltd All rights reserved - Copyright date: - 2016 - Notes: - This is the author accepted manuscript following peer review version of the article. The final version is available online from Elsevier at: 10.1016/j.ejogrb.2016.12.002 If you are the owner of this record, you can report an update to it here: Report update to this record

Text is read by the "Ask this paper" AI Q&A widget below. Extraction quality varies by source — PMC NXML preserves structure cleanly, OA-HTML may include some navigation residue, and OA-PDF can have broken hyphenation. The publisher copy (via DOI) is the canonical version.

My notes (saved in your browser only)

⚙ Ask this paper AI returns verbatim quotes from the full text · source: oa-html ⓘ

Answers must be backed by verbatim quotes from this paper's full text. Hallucinated quotes are dropped automatically; if no verbatim passage answers the question, we say so. How this works

Condition tags

endometriosischronic_pelvic_pain

MeSH descriptors

CA-125 Antigen Endometriosis Membrane Proteins Adult Biomarkers Biomarkers CA-125 Antigen Endometriosis Endometriosis Female Humans Infertility, Female Infertility, Female Membrane Proteins Pelvic Pain Pelvic Pain Prospective Studies

Citation neighborhood

Papers in the corpus that this work cites (lower rings, blue) and that cite this one (upper rings, green). Dot size scales with the paper's in-corpus citation count — bigger dot = more influential within the endo/adeno field. Click a dot to open that paper. [ expand to 2 hops ] — adds papers reached through this work's immediate citers/citees. Heavier; up to 60 extra dots.

References (25)

Cited by (50)

Source provenance

europepmc
last seen: 2026-08-25T06:10:03.373225+00:00
openalex
last seen: 2026-06-10T17:14:06.276822+00:00
pubmed
last seen: 2026-05-13T22:20:43.714878+00:00
License: CC0 · commercial use OK