High CA-125 concentrations in peritoneal fluid of normal cyclic women with various infertility-related factors as demonstrated with two-step immunoradiometric assay

Diagnostic accuracy of cancer antigen 125 for endometriosis: a systematic review and meta-analysis

BACKGROUND

The development of a non-invasive and accurate diagnostic biomarker for endometriosis is urgently needed.

OBJECTIVE

Evaluate the diagnostic accuracy of serum cancer antigen 125 (CA 125) for endometriosis.

SEARCH STRATEGY

We searched EMBASE, MEDLINE, and Web of Science from inception to January 2016.

SELECTION CRITERIA

Diagnostic accuracy studies of serum CA 125 (index test) for histologically confirmed endometriosis (reference standard) were included.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, extracted study characteristics and data. Methodological quality was assessed using Quality Assessment of Comparative Diagnostic Accuracy Studies (QUADAS-2) checklist.

MAIN RESULTS

Twenty-two studies (16 cohort, six case-control), 3626 participants, were identified. Bivariate hierarchical models were used to pool accuracy data of 14 studies (2920 participants) using CA 125 ≥ 30 units/ml. Pooled specificity was 93% (95% CI 89-95%) and sensitivity 52% (95% CI 38-66%). CA 125 was significantly more sensitive for the diagnosis of moderate or severe endometriosis compared with minimal disease (63%, 95% CI 47-77% versus 24%, 95%CI 19-32%, P-value = 0.001).

CONCLUSIONS

CA 125 performs well as a rule-in test facilitating expedited diagnosis and ensuring investigation and treatment can be confidently tailored for the management of endometriosis. Unfortunately, a negative test, CA 125 < 30 units/ml, is unable to rule out endometriosis.

TWEETABLE ABSTRACT

Blood test CA 125: a rule-in test for the diagnosis of women presenting with symptoms of endometriosis.

Anesthetic evaluation and management of a patient with thoracic endometriosis syndrome presenting for elective surgery

Thoracic endometriosis syndrome is a relatively uncommon disorder characterized by recurrent pneumothoraces, hemothorax, chest pain, dyspnea, and hemoptysis within 48 to 72 hours of menstruation. A 34 year old, ASA physical status 2 woman with recurrent catamenial pneumothoraces due to thoracic endometriosis syndrome is presented. After treatment with video-assisted thoracoscopic surgery, she underwent successful elective diagnostic abdominal laparoscopy without incident. The presence of parenchymal injury and damage predisposes these patients to ventilator-induced lung injury. Postponement of surgery until the intermenstrual period, with lung protective ventilation, allows patients with this disease to successfully undergo general anesthesia and surgery.

The effect of endometriosis, cycle stage, lymphocyte suppression and pregnancy on CA-125 levels in peritoneal fluid and serum in baboons

BACKGROUND

Serum CA-125 during the mid-follicular phase has been reported to be a clinically useful and reproducible marker in the diagnosis of advanced endometriosis in women. This study was undertaken to document the effect of the menstrual cycle, pregnancy and lymphocyte suppression on CA-125 levels in peritoneal fluid (PF) and serum in baboons with a normal pelvis and baboons with endometriosis.

METHODS

CA-125 levels were measured in 264 serum samples that were serially obtained during one menstrual cycle from 10 animals with and without endometriosis. In addition, CA-125 levels were determined in 204 archived samples (serum, n = 112 and PF, n = 92) obtained from 32 female baboons with or without endometriosis. The CA-125 assays were performed by radioimmunoassay using kits from Centocor (Malvern, PA, USA).

RESULTS

Serum CA-125 levels were at their highest during menstruation and decreased progressively during the follicular and luteal phase. PF CA-125 levels were increased during the follicular phase in baboons with a normal pelvis, but no cyclic changes were observed in animals with endometriosis. Serum CA-125 levels were unaffected by induction, lymphocyte suppression or pregnancy. Induction of endometriosis resulted in increased PF CA-125 levels, whereas lymphocyte suppression or pregnancy had no effect.

CONCLUSION

In baboons, serum CA-125 originates mainly from eutopic endometrium whereas the main source of PF CA-125 seems to be the peritoneum or ectopic endometrium. The baboon appears to be a valid model to further study the relationship between endometriosis and CA-125.

Laboratory testing for endometriosis

BACKGROUND

Typically, endometriosis is diagnosed surgically by laparoscopy. CA-125 is the principal serum marker used in the diagnosis and management of late-stage endometriosis. The search for a body fluid marker of early stage disease has included studies of serum, peritoneal fluid (PF), and/or tissue levels of secretory proteins, cell adhesion molecules, cytokines, tumor necrosis and vascular endothelial growth factors (VEGFs), chemokines, antiendometrial antibodies, autoantibodies to oxidized lipoproteins, aromatase P-450 expression, cytokeratins, and hormone receptors. We compared the diagnostic accuracy and clinical utility of these various types of substances in the non-surgical identification of patients with endometriosis.

METHOD

We reviewed the MEDLINE database for all publications on serum, peritoneal fluid and tissue markers of endometriosis.

RESULTS

Except for serum interleukin (IL)-6 and peritoneal fluid tumor necrosis factor (TNF)-alpha levels, the diagnostic accuracy of other markers of endometriosis was either similar or worse than that of CA-125 (sensitivity 24-94%; specificity 83-93%). The diagnostic accuracy of IL-6 and TNF-alpha was 90-100% (sensitivity) and 67-89% (specificity).

CONCLUSION

CA-125 has limited diagnostic accuracy in the identification of early stage endometriosis and none of the other markers we reviewed dramatically outperformed CA-125 in this regard with the possible exception of serum IL-6 and peritoneal fluid TNF-alpha levels.

The performance of CA-125 measurement in the detection of endometriosis: a meta-analysis

OBJECTIVE

To assess the diagnostic performance of serum CA-125 measurement in the detection of endometriosis.

DESIGN

Meta-analysis.

SETTING AND PATIENT(S)

Twenty-three studies comparing serum CA-125 levels and laparoscopically confirmed endometriosis.

INTERVENTION(S)

Serum CA-125 measurement and laparoscopy.

MAIN OUTCOME MEASURE(S)

Sensitivity and specificity of serum CA-125 measurement in the diagnosis of endometriosis with laparoscopy as the reference standard.

RESULT(S)

The estimated summary receiver operating characteristic curves showed that the performance of serum CA-125 measurement in the diagnosis of endometriosis grade I/IV is limited, whereas its performance in the diagnosis of endometriosis grade III/IV is better.

CONCLUSION(S)

Despite its limited diagnostic performance, we believe that the routine use of serum CA-125 measurement in patients with infertility might be justified. In contrast to laparoscopy, serum CA-125 measurement is an inexpensive test that is not a burden for the patient. It could identify a subgroup of patients who are more likely to benefit from early laparoscopy. Studies reporting on the mutual dependence between serum CA-125 measurement and data from the history and physical examination are needed.

Serum and peritoneal CA-125 levels as diagnostic test for endometriosis

OBJECTIVE

To evaluate the clinical utility of CA-125 in the diagnosis of endometriosis and to compare the sensitivity of the serum and the peritoneal test as indicator of disease.

STUDY DESIGN

Peritoneal fluid was obtained at laparoscopy. The quantitative determination of CA-125 in serum and in peritoneal fluid was performed by IRMA-mat CA-125 'two-step method', a two-site immunoradiometric assay, using 35 and 60 U/ml as cutoff.

SETTING

Second Department of Gynecology and Obstetrics, Second University of Naples, Italy.

PARTICIPANTS

A total of 26 women infertile undergoing diagnostic laparoscopy that exhibited endometriosis in 14 patients, normal pelvis in 12 patients (control group).

INTERVENTIONS

None.

RESULTS

CA-125 levels in peritoneal fluid were higher than those found in serum and were significantly elevated (P < 0.05), when compared with the control group, both in women with endometriosis stage I-II and stage III-IV. In serum, CA-125 levels increased only in advanced stage of endometriosis.

CONCLUSIONS

Levels of CA-125 in peritoneal fluid seem to be a more sensitive indicator of disease than serum levels (0.86 vs. 0.36), especially in early stage endometriosis (0.80 vs. 0.20) which tends to be overlooked by the CA-125 serum test.

No evidence of the hook effect in peritoneal fluid CA 125 measurement using immunoenzymatic second generation assays: comparison with immunoradiometric assays

OBJECTIVE

To monitor the occurrence of the hook effect in measurements of peritoneal fluid CA 125 levels using two different immunoenzymatic second generation assays (ETI-II and EIA-II), and to compare these results with those obtained using the respective immunoradiometric versions of the assays (IRMA-II and ELSA-II).

STUDY DESIGN

CA 125 levels were determined in peritoneal fluid and serum samples obtained from 45 women with gynecological diseases. The assays were carried out using IRMA-II and ETI-II (Sorin Biomedica) and ELSA-II and EIA-II (CIS Bio International) assays. Occurrence of the hook effect and linearity of the assays were evaluated. Statistical analyses were performed by Wilcoxon's test and linear regression analysis.

RESULTS

Undiluted peritoneal fluids, assayed for their CA 125 content, showed falsely underestimated values of the antigen when IRMA-II and ELSA-II assays were performed. The phenomenon disappeared only at high dilutions of the sample (> 50). Conversely, immunoenzymatic ETI-II and EIA-II assays performed on undiluted peritoneal fluids did not show underestimated CA 125 values. CA 125 values obtained by immunoenzymatic assay were lower than those obtained using their respective immunoradiometric versions at a dilution of 1:100 (P < 0.001). A good correlation was observed between ELSA-II and EIA-II (r = 0.929) CA 125 values.

CONCLUSION

The EIA-II immunoenzymatic assay appears to be more suitable for CA 125 measurement in peritoneal fluid in that it is not subject to the hook effect and its results correlated well with those obtained via its immunoradiometric version.

CA-125 levels in cervical mucus during the menstrual cycle

OBJECTIVE

To determine CA-125 levels in cervical mucus (CM) during the menstrual cycle and their relationship to gonadal steroids and ovulation.

DESIGN

Prospective study.

SETTING

Two academic tertiary referral centers.

PARTICIPANTS

Thirteen women with a normal fertility work-up.

INTERVENTIONS

CA-125 and protein concentrations were measured in CM aspirated from the endocervical canal on alternate days in the early follicular and luteal phases and on a daily basis during the periovulatory period. Results were correlated with hormonal determinations, serum CA-125 levels, and ultrasound examination.

RESULTS

Twenty ovulatory nonconceptional cycles were analyzed. Although the mean (+/- SD) concentration of CA-125 in CM (173,900 +/- 128,900 arbitrary U/mL) appeared relatively constant along the cycle, a large variation among the different samples was observed, ranging from 9,000 to 830,000 arbitrary U/mL. No clear trend could be detected as related to hormonal changes and ovulation. However, when the mucus CA-125 concentration was multiplied by the total volume of the correspondent sample, a clear periovulatory increase of total CA-125 levels was found. This was further supported by a similar trend showed by the calculated CA-125:protein concentration ratio.

CONCLUSIONS

CA-125 is present in CM in high concentrations that vary widely along the cycle. Although no cyclical variation in CA-125 concentration could be determined, there was an apparent increase of total CA-125 levels parallel to the augmented mucus production during the periovulatory period. This further suggests a possible involvement of this glycoprotein in the secretory process of endocervical glands.

Tumour-associated antigens, CEA, CA 125 and SCC in serum and follicular fluid of stimulated and unstimulated cycles

Serum and follicular fluid levels of CEA, CA 125 and SCC of women participating in an IVF program, in 42 cycles stimulated with GnRH-a and gonadotropins and in 26 unstimulated cycles triggered with HCG, were evaluated and compared with (a) steroid and gonadotropin levels, (b) the results of IVF, and (c) serum values in a control group of women with spontaneous normal ovulatory cycles. In the control group, serum antigens did not vary significantly during the 3 phases of the cycle. In stimulated cycles the median values in serum were 0.7 ng/ml (range, 0.0-2.1) for CEA, 14.0 U/ml (3.3-32.4) for CA 125 and 2.05 ng/ml (1.1-17.8) for SCC, whereas the median values in follicular fluid were 0.6 (0.0-27.9), 21.5 (0-670) and 21.4 (1-360), respectively. In unstimulated cycles the median values and ranges in serum were 0.9 (0.4-3.9), 12.1 (4.8-63.4) and 1.85 (0.7-4.4), respectively, whereas in follicular fluid they were 2.9 (0.4-180.7), 32 (1.7-600) and 231 (10.8-904). Different follicles of the same patients in stimulated cycles showed a wide divergence for all three antigens. In unstimulated cycles all three antigens in follicular fluid were strongly-correlated and a significant inverse correlation was observed between LH and both CA 125 and SCC in serum. In either group of cycles, no significant relationship was found between any serum or follicular fluid antigen and estradiol or testosterone, pregnancy rate, or oocyte quality and fertilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Serum and peritoneal fluid CA-125 levels in patients with endometriosis

OBJECTIVE

To evaluate CA-125 in peritoneal fluid (PF) as an indicator of endometriosis.

DESIGN

CA-125 levels in paired serum and PF were determined by the one-step immunoradiometric assay. For peritoneal samples, high dilution of the sample (1:100) was used to avoid false low results, caused by the "hook effect" phenomenon.

PATIENTS

Forty-one women with and without endometriosis, undergoing laparoscopy or laparotomy during the follicular phase of the menstrual cycle, were selected.

SETTING

2nd Institute of Obstetrics and Gynecology, University of Rome "La Sapienza," Rome, Italy.

MAIN OUTCOME MEASURE

Peritoneal fluid CA-125 levels obtained using diluted samples were significantly higher than those found using undiluted ones.

RESULTS

CA-125 levels in PF were approximately 100 times higher than those found in paired serum, ranging from 970 to 10,636 U/mL. In patients with endometriosis, CA-125 levels in PF were significantly elevated when compared with the control group. In serum, CA-125 levels increased only in advanced stages of endometriosis.

CONCLUSIONS

The sensitivity of the CA-125 test for endometriosis in PF is greater than in serum. Therefore, the measurement of CA-125 levels in PF could be useful in the detection of early stage endometriosis, which tends to be overlooked by the CA-125 serum test.

Menstruation as the pelvic aggressor

Cumulative evidence supports the concept of retrograde menstruation being a pelvic aggressor as it contributes to both the development of endometriosis and related symptoms such as dysmenorrhoea and infertility. A major problem in studying the association between these entities (retrograde menstruation, endometriosis, dysmenorrhoea and infertility) is the lack of an accurate method to quantify the amount of retrograde menstruation.

Markers for endometriosis

Screening for endometriosis is subject to general rules. The two most important conditions, i.e. the disorder should be well-defined and serious, and there must be an effective way to treat or prevent it through screening, are not satisfied for endometriosis. Given the lack of understanding of the pathogenesis of this disease and the disreputable evidence of treatment effectiveness, other criteria for worthwhile screening programmes, such as prevalence, cost effectiveness and screening test performance, cannot be evaluated. Markers may be applied in the diagnostic process in the individual patient, although it should be realized that the best results will be obtained in patients with advanced disease, in whom routine pelvic examination will establish the diagnosis on purely clinical grounds anyway. The development of appropriate tissue markers may in the future shed more light on the intricate mechanisms involved in the pathogenesis of endometriosis.