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

The Known, the Unknown and the Future of the Pathophysiology of Endometriosis

Endometriosis is one of the most common causes of chronic pelvic pain and infertility, affecting 10% of women of reproductive age. A delay of up to 9 years is estimated between the onset of symptoms and the diagnosis of endometriosis. Endometriosis is currently defined as the presence of endometrial epithelial and stromal cells at ectopic sites; however, advances in research on endometriosis have some authors believing that endometriosis should be re-defined as "a fibrotic condition in which endometrial stroma and epithelium can be identified". There are several theories on the etiology of the disease, but the origin of endometriosis remains unclear. This review addresses the role of microRNAs (miRNAs), which are naturally occurring post-transcriptional regulatory molecules, in endometriotic lesion development, the inflammatory environment within the peritoneal cavity, including the role that cytokines play during the development of the disease, and how animal models have helped in our understanding of the pathology of this enigmatic disease.

Cancer antigen 125 assessment using carbon quantum dots for optical biosensing for the early diagnosis of ovarian cancer

Fluorometric quantification of biological molecules is a key feature used in many biosensing studies. Fluorescence resonance energy transfer (FRET) using highly fluorescent quantum dots offers highly sensitive detection of the in-proximity wide variety of analyst molecules. In this contribution, we report the use of carbon quantum dots (CDs) for the ultrasensitive optical biosensing of cancer antigen 125 (CA-125) in the early malignant stage. This approach is based on monitoring the quenching of CDs luminescence at 535 nm by CA-125 after excitation at 425 nm and pH 10. The calibration of this method was performed in the concentration range of CA-125 from 0.01 to 129 U ml⁻¹ (R² = 0.99) with a detection limit of 0.66 U ml⁻¹, which matches remarkably with the standard chemiluminometric method in control and real patient samples. The sensing mechanism for cancer antigen 125 assessment was discussed on the basis of fluorescence quenching of CDs and time-resolved photoluminescence spectroscopy. The current method is easy, sensitive, cost-effective and provides a wide range of validity, which helps in overcoming the limitations of high cost and time consumption exhibited by many other traditional clinical assays for CA-125 quantification.

Fluorometric quantification of biological molecules is a key feature used in many biosensing studies.

Spontaneous endometriosis in cynomolgus monkeys as a clinically relevant experimental model

STUDY QUESTION

Does spontaneous endometriosis in cynomolgus monkeys have the characteristics required of a good experimental model?

SUMMARY ANSWER

Spontaneous endometriosis in cynomolgus monkeys exhibited similar clinicopathological characteristics to the human disease and was useful as an experimental model.

WHAT IS KNOWN ALREADY

The prevalence of endometriosis in autopsied cynomolgus monkeys (Macaca fascicularis) in a breeding colony was reported to be 28.7% in 1993. The histopathological findings we reported recently showed that components of spontaneous endometriosis were not only endometriotic epithelium and stromal cells (CD10-positive) with hemorrhage and inflammation, but also smooth muscle metaplasia and nerve fibers.

STUDY DESIGN, SIZE, DURATION

During routine medical examinations at a research facility from 2008 to 2012, 614 female cynomolgus monkeys of reproductive age (6-25 years) were screened for endometriosis by the presence of regular menstrual bleeding, serum CA125 levels and palpation of the abdomen. In total, 29 monkeys were selected as subjects for the following study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Of the 29 monkeys selected, 15 were diagnosed with endometriosis by laparoscopy and/or open surgery. The monkeys were monitored by observing their general condition, and eight of these were monitored using laparoscopy and MRI. In addition, to investigate appropriate screening parameters and endometriosis-associated biological parameters in monkeys, we retrospectively examined general laboratory parameters that correlate to the menstrual cycle and disease status.

MAIN RESULTS AND THE ROLE OF CHANCE

The combination of CA125 serum levels (this was a useful marker for chocolate cysts), palpation of the abdomen, and fecal abnormalities was the most efficient screening method for diagnosing monkeys with endometriosis. Each animal could be diagnosed and assigned a disease stage by laparoscopy. While monitoring the disease stage by laparoscopy and/or MRI, disease status in individual monkeys was mainly stable or was progressive for 2-7 months. The detection rate by screening was low (15/614) but age-specific analysis suggests that screening would be more efficient if a colony for an endometriosis model is maintained with 11-20-year olds. As an endometriosis-associated biological parameter, the decrease in food consumption that coincided with menstruation was selected and correlated well (R2 value = 0.8239) with disease status (according to a modified adhesion revised American Fertility Society score).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Peritoneal fluid was not analyzed because a smaller amount is produced in cynomolgus monkeys than in baboons. Although clinical endometriosis-associated pain is evaluated in women using a visual analog scale, pain could not be directly evaluated in this non-human primate model.

WIDER IMPLICATIONS OF THE FINDINGS

Although cynomolgus monkeys are relatively small (2-5 kg) primates, laparoscopy and MRI make it possible to evaluate spontaneous endometriosis in these monkeys and to monitor its development over time. Spontaneous endometriosis in cynomolgus monkeys is a useful model for evaluating disease progress and drug efficacy because they have similar lesions to those in humans, and conventional laboratory methods and parameters for assessment are well established.

STUDY FUNDING/COMPETING INTEREST(S)

No external funds were used for this study. A.N.-K., K.T., H.T., A.K. and M.S. are full-time employees of Chugai Pharmaceutical Co., Ltd. R.K. received a consultancy fee from Chugai Pharmaceutical Co., Ltd. and lecture fees from Chugai Pharmaceuticals, Japan Vaccine Co. Ltd., Merck & Co., Mochida Co. Ltd., Roche Diagnostics, and BD, unrelated to the submitted work. S.N., S.O. and T.S. have nothing to declare.

High CA-125 and CA19-9 levels in spontaneous ruptured ovarian endometriomas

BACKGROUND

To evaluate the clinical significance of serum CA-125 and CA19-9 in women with spontaneous ruptured ovarian endometriomas.

METHODS

From January 2006 to April 2015, a total of 1653 women were diagnosed with ovarian endometriomas, and 43 women were diagnosed with the spontaneous rupture of their ovarian endometrioma. In addition, 70 women diagnosed with unruptured ovarian endometriomas were chosen to serve as control subjects. Serum CA-125 and CA19-9 levels, together with the clinical materials, were collected.

RESULTS

Serum CA-125, CA19-9, and the combined biomarkers were shown to be obviously elevated in the spontaneous ruptured ovarian endometrioma group (p=0.001, p=0.001, p=0.001, respectively). The AUC value for the combined biomarkers was 0.992 (95% CI, 0.981-1.000), with a high sensitivity and specificity of nearly 100% and 93.6%, respectively. Moreover, the maximum diameter of the mass was significantly (p=0.001) increased in the ruptured group.

CONCLUSIONS

Serum CA-125 and CA19-9 were significantly increased in patients with spontaneous ruptured ovarian endometriomas. Moreover, the combined biomarkers were better than either CA-125 or CA19-9 alone in the diagnosis of a spontaneous rupture of the ovarian endometrioma.

Cancer antigen 125 after delivery in women with a normal pregnancy: a prospective cohort study

OBJECTIVE

To establish reference intervals for cancer antigen 125 (CA-125) in women with expected normal pregnancy, delivery, and early postpartum period.

DESIGN

Prospective observational study.

SETTING

Department of Clinical Biochemistry and Obstetrics, Copenhagen University Hospital, Gentofte, Denmark.

POPULATION

Eight hundred and one women with expected normal pregnancies were investigated. Of these, 640 delivered vaginally, 82 by emergency cesarean section, and 79 by elective cesarean section; 720 women had uncomplicated pregnancies.

METHODS

Samples were collected at gestational weeks 13-20, 21-28, 29-34, 35-42, during labor, and on first and second day postpartum. Reference intervals were calculated for each gestational period as recommended by the International Federation of Clinical Chemistry and Laboratory Medicine.

MAIN OUTCOME MEASURES

Concentration of serum CA-125 during the gestational period and around delivery.

RESULTS

CA-125 was fairly stable below 35 U/mL during pregnancy but increased markedly during vaginal delivery, to a minor degree during emergency cesarean section, and only slightly during elective cesarean section. In the early postpartum period, CA-125 decreased with an apparent half-life of 24 h.

CONCLUSIONS

The CA-125 cut-off value (<35 U/mL) used for non-pregnant women can be used for women during pregnancy after gestational week 13 as a supplement to ultrasound evaluation of ovarian cysts. The wide range of CA-125 concentration during normal pregnancies makes it unlikely that small fluctuations in CA-125 can be clinically useful for identifying other conditions. Measuring CA-125 around the time of delivery is not recommended. Gestational age-specific reference intervals during normal pregnancy are not needed.

Interleukin-6 and other soluble factors in peritoneal fluid and endometriomas and their relation to pain and aromatase expression

Immunological changes and gene expression anomalies are involved in the etiopathophysiology of endometriosis, although how these alterations are connected is not well established. The aim of this study was to determine the relationship between levels of immune cell populations, cytokines and CA-125 in peritoneal fluid (PF) and 'chocolate' cyst fluid (CF), and aromatase expression in endometriotic tissue, as well as to investigate any association with symptoms or recurrence of the disease. Eutopic and ectopic endometrium, CF and PF were collected from 84 women with endometriomas and 24 with benign non-functioning ovarian tumors undergoing radical or conservative surgery. Immunohistochemistry was performed to determine aromatase expression. PF cell populations were assessed by flow cytometry, and CF and PF levels of interleukin (IL)-6, IL-8, IL-13, IL-17 and CA-125 were quantified by ELISA. These parameters were compared with aromatase expression, symptoms and recurrence of the disease. IL-6 levels in PF were higher in patients with endometriosis than in patients with benign non-functioning ovarian cysts, and correlated positively to dysmenorrhea and pelvic pain in the first group. An association between PF IL-8 and CA-125 was also observed in endometriosis. Aromatase positive patients showed higher levels of PF CA-125 and CF IL-17. Recurrence of symptoms or endometrioma occurred sooner in patients having higher IL-6 or IL-8 levels in CF, respectively. These findings suggest an association of IL-6 with pain in endometriosis, as well as a relationship between cytokine expression and recurrence of the disease. However no clear relationship between aromatase expression and other parameters was found.

Frequency of endometriotic lesions in peritoneum samples from asymptomatic fertile women and correlation with CA125 values

CONTEXT AND OBJECTIVE

Serological testing for CA125 has been widely used to detect endometriosis and to monitor its progression. However, controversy still exists regarding the usefulness of the plasma CA125 assay for diagnosing endometriosis. Furthermore, some authors have described superficial endometriosis as a cyclical and normal phenomenon in women's lives, and have indicated that development and progression of this disease would only occur in some women as a result of immunological changes. This study aimed to determine the frequency of endometriosis and the correlation between serum CA125 levels and the presence of endometriotic lesions in the peritoneum of asymptomatic fertile patients.

DESIGN AND SETTING

Cross-sectional study at the Family Planning outpatient clinic of Faculdade de Medicina do ABC.

METHODS

Eighty asymptomatic fertile patients who underwent tubal sterilization surgery were studied. Blood and peritoneum samples were collected. CA125 levels were measured from blood samples, and peritoneum biopsies were studied using histopathological tests.

RESULTS

Histopathological evaluation of the peritoneum revealed that 16.25% of the patients had minimal or mild endometriosis. There was no statistically significant difference in CA125 levels between patients with and without endometriosis.

CONCLUSION

The presence of endometriotic lesions in the peritoneum of fertile patients supports the hypothesis that incidental findings of minimal or mild endometriosis may not be of clinical significance, and that the progression of the disease probably occurs as a result of immunological and genetic abnormalities. Serum CA125 levels did not show any diagnostic significance with regard to detecting the disease.

Nonhuman primate models for translational research in endometriosis

Endometriosis, defined as the ectopic presence of endometrial-like cells, is associated with infertility and pelvic pain in women. Whereas pathogenesis and spontaneous evolution of endometriosis are still poorly understood, recurrences after surgical therapy or after medical treatment are common. Spontaneous endometriosis occurs only in women and in nonhuman primates (NHPs). Inbred rhesus monkeys kept in colonies offer an attractive preclinical model to study the inheritance of spontaneous endometriosis. Baboons with spontaneous or induced endometriosis appear to be the best NHP model to study pathogenesis, pathophysiology, spontaneous evolution and new medical treatment options. In baboons, induction of endometriosis after intrapelvic injection of menstrual endometrium leads to biological changes in peritoneal cavity and in endometrium. This induction process may allows the study of cause-effect relationships which may lead to the discovery of new biomarkers for the development of new non-invasive diagnostic tests and drugs that may prevent or treat endometriosis.

Identifying biomarkers of endometriosis using serum protein fingerprinting and artificial neural networks

OBJECTIVES

To use surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) protein chip array technology to detect proteomic patterns in the serum of women with endometriosis; build diagnostic models; and evaluate their clinical significance.

METHODS

Serum samples from women with endometriosis and healthy women were studied using SELDI-TOF-MS protein chip technology. For every matched pair, two-thirds of the samples were used to look for different patterns and one-third was used for cross-validation.

RESULTS

Five potential biomarkers were found and the diagnostic system distinguished endometriosis from validation samples with a sensitivity of 91.7% and a specificity of 90.0%.

CONCLUSION

This method shows great potential in identifying biomarkers to be used for endometriosis screening.

Endometriosis: clinical monitoring and treatment procedures in Rhesus Monkeys

The National Institute on Aging (NIA) sponsored a workshop on September 8, 2004, to discuss the incidence, diagnosis, and clinical treatment of endometriosis in rhesus monkey colonies. Because of the growing number of aging studies using rhesus monkeys, this disease has become more prevalent as monkeys are living into advanced ages in captivity. The objective of the workshop was to gather information from various NIA-supported aging rhesus colonies on the incidence, clinical manifestations, indicators for early detection, and possible treatment options for endometriosis. Participants outlined a course of action for the effective management of this disease that would best maintain the integrity of long-term aging studies.

Extremely elevated serum CA-125 level as a result of unruptured unilateral endometrioma: the highest value reported

OBJECTIVE

To present a case of a unilateral endometrioma with extremely elevated serum CA-125 levels.

DESIGN

Case report.

SETTING

University hospital.

PATIENT(S)

A 25-year-old woman with left adnexal mass and extremely elevated serum CA-125 level, 7,900 U/mL, underwent laparoscopy. There were unilateral endometrioma and stage IV endometriosis.

INTERVENTION(S)

Laparoscopic excision of the endometrioma, unilateral salpingectomy, adhesiolysis, ablation of endometriotic foci, and partial omentectomy were performed, and histopathologic results confirmed the diagnosis of endometriosis.

MAIN OUTCOME MEASURE(S)

Extremely elevated serum CA-125 levels and unruptured ovarian endometrioma.

RESULT(S)

On the second, sixth, and 13th days of the menstrual period, serum CA-125 levels were 7,900 U/mL, 1,577 U/mL, and 627 U/mL, respectively. On the third postoperative day serum CA-125 level was 56 U/mL.

CONCLUSION(S)

Ovarian endometrioma and advanced endometriosis may be associated with extremely elevated serum CA-125 levels. For this reason ovarian endometrioma should be considered with respect to differential diagnosis of reproductive-age women presenting with an ovarian mass even if it resembles an ovarian malignancy.