General articles Ref: Ro J Med Pract. 2021;16(1) DOI: 10.37897/RJMP.2021.1.5 Minimally invasive diagnosis of endometriosis Cătălina Diana STANICA, Adrian NEACSU, Romina Marina SIMA, Raluca Gabriela IOAN Departament of Obstetrics and Gynecology, ”Carol Davila” University of Medicine and Pharmacy, Bucharest Abstract Endometriosis is a common condition among women of reproductive age that can cause chronic pelvic pain and infertility. Rapid establishment of a positive diagnosis of endometriosis is essential for effective management. The positive diagnosis of endometriosis is difficult to establish and requires invasive methods. The "golden standard" for diagnosis is still laparoscopy. Current research has not yet established specific non-invasive diagnostic methods for endometriosis. Imaging techniques, endometrial or serum markers facilitate diagnosis and are useful in monitoring the patient's progress. A number of noninvasive investigations, such as imaging techniques, or biomarkers are currently being evaluated for use in routine practice. A combination of these noninvasive tests could be the standard for diagnosing endometriosis in the future. Keywords: endometriosis, noninvasive diagnosis, imaging diagnosis INTRODUCTION menstrual pain), infertility, dysuria, rectal tenesmus, hematuria, hemoptysis, the diagnosis of endometriosis Endometriosis is a common gynecological condi- should be considered. The symptoms have a cyclical tion, found in women of reproductive age, with impor- character, similar to the menstrual cycle (1). tant implications for their quality of life and married The positive diagnosis of endometriosis involves life. The costs involved in the diagnosis and treatment the use of invasive methods that allow the visualization of endometriosis, not negligible, have special so- of lesions and the taking of tissue samples from suspi- cio-economic consequences. cious lesions. The anatomo-pathological examination The exact pathophysiological mechanisms involved of the samples taken establishes the diagnosis of cer- in the onset and progression of the disease are not tainty. This is currently the „gold standard” in the diag- known. Endometriosis can be classified as adenomyo- nosis of endometriosis (2). There is currently no mini- sis (endometriosis developed in the thickness of the mally invasive paraclinical test to establish a definite myometrium) and endometriosis itself (development diagnosis of endomertiosis. Currently available investi- of ectopic endometrial tissue outside the uterus), with gations supplement only clinical data, strengthening genital or extragenital location, can affect the large in- the suspicion of the diagnosis of endometriosis and testine at different levels, appendix, urinary tract, res- also allowing monitoring of treatment. piratory tract brain, skin etc. About 10% of women of reproductive age suffer In the case of a woman of childbearing age who has from endometriosis, and recent epidemiological data chronic pelvic pain (dysmenorrhea, dyspareunia, inter- show an increase in the incidence of the disease (3). Corresponding author: Article History: Catalina Diana Stanica Received: 08 March 2021 E-mail: [email protected] Accepted: 16 March 2021 ROMANIAN JOURNAL OF MEDICAL PRACTICE – VOL. XVI, NO. 1 (75), 2021 25 ROMANIAN JOURNAL OF MEDICAL PRACTICE – VOL. XVI, NO. 1 (75), 2021 The condition affects a woman’s quality of life and re- (10,11). However, its sensitivity and specificity are low, productive potential, by decreasing fertility. The dis- with elevated plasma levels being found in other condi- covery of non-invasive diagnostic tests, of population tions (epithelial neoplasms, pericarditis, pancreatitis screening methods, which would allow the start of etc.). treatment from an early stage, would therefore be very Serological markers such as the antigens CA-72, CA useful. 15-3, CA 19-9, TAG-72 have not yet demonstrated their The development of imaging methods, the extraor- utility in the diagnosis of endometriosis (12-14). In the dinary advances registered in the field of genetics, of case of placental protein 14 (PP14) there is a very good the study of biological, cellular and molecular markers, correlation with the stage of the disease (15,16). Also, constitute premises for the discovery of new efficient the specificity for diagnosing endometriosis when de- methods of diagnosis and treatment in endometriosis. termining antiendometrial antibodies can reach almost 100% (17,18). OBJECTIVE AND METHOD In endometriosis, cytokines (19,20) appear to have a profound effect on the implantation of endometriotic The objective of this paper was to identify in the sources by reducing immunological surveillance and literature new minimally invasive methods for diagnos- identifying and destroying endometrial cells. Of these, ing endometriosis. IL-6 has been the most studied in recent decades, with We searched in electronic databases (PubMed, good sensitivity and specificity. However, it is better Google Scholar) articles and clinical studies published that future studies focus on the diagnostic efficacy of in recent years, which identify minimally invasive meth- IL-6 combined with other cytokines. ods for diagnosing endometriosis. We selected only In an attempt to pinpoint the existence and location the materials that specify that they went through the of endometriotic implants as accurately and less inva- peer review procedure. sively as possible, the use as markers of substances that specifically combine with surface receptors of ec- BIOMARKERS USED TO DETECT topic endometrial tissue is tested. Laser-induced lumi- nescence is based on the fact that a tissue, exposed to ENDOMETRIOSIS light of a certain wavelength, emits fluorescence in a The definite diagnosis of endometriosis still involves specific spectrum, as well as some tissue-specific drugs. invasive techniques (laparoscopy and laparotomy). It was found that tamoxifen has the best concentration Current research seeks to establish non-invasive, relia- in endometriotic implants, its highlighting can be done ble, relatively low-cost methods for diagnosing endo- with an argon-ion laser (21). A similar method is based metriosis. on the use of 5-aminolevulinic acid that accumulates in Understanding the pathophysiological mechanisms endometriotic tissue, where it is converted to pro- involved in the onset and progression of endometriosis toporphyrin IX, which has the ability to emit fluores- has led to the study of a large number of possible bio- cent (22). logical, cellular or molecular markers that could have There are studies of monoclonal antibodies that practical utility in the diagnosis of endomertiosis (4,5). bind specifically to target endometriotic cells that facil- Hormonal, immunological mechanisms are studied, itate the definite diagnosis of endometriosis, but also which involve adhesion molecules and cellular recep- open up new therapeutic options for the use of cyto- tors, as well as biochemical changes in the eutopic or toxic substances or inhibitors of ectopic endometrial ectopic endometrium. Many of the studies have had activity related to these “carrier” (23). promising results in animal or in vitro models, not in Studies have found that miRNAs obtained from dis- human patient studies, but research is ongoing. eased tissues and other body fluids have been able to In recent years, a number of serological markers, detect various diseases (24). MiRNA deregulation is in- peritoneal fluid, or menstrual flow have been studied volved in the pathophysiology of endometriosis and (6-9). has been investigated as potential biomarkers, howev- The most widely used serological marker today is er additional validations in a large population using a the CA-125 antigen. This is a high molecular weight sur- standardized reproducible methodology to further face glycoprotein (20 Kilodaltons), whose serum con- clarify the diagnostic potential of miRNAs. centration increases in women with endometriosis, There are studies on the altered expression of cer- correlated with the stage of the disease. The marker is tain genes in endometriotic implants, or protein sub- useful in monitoring treatment (values decrease after sets secreted by ectopic endometrial tissue (25-27). administration of danazol or GnRh agonists), or in mon- Out of a total number of 4,133 genes studied, 8 genes itoring the recurrence of post-therapeutic disease were identified as altered in endometriotic tissue. 26 ROMANIAN JOURNAL OF MEDICAL PRACTICE – VOL. XVI, NO. 1 (75), 2021 IMAGING METHODS FOR DIAGNOSING Another useful investigation in the positive diagno- ENDOMETRIOSIS sis of endomeriosis is sonohisterography. This was pro- posed for further study of salpinges (41), being a com- The two-dimensional transvaginal ultrasound ex- bination of transvaginal ultrasound and instillation into amination proved to be very useful in detecting ovarian the uterine cavity of a saline or opaque solution follow- endometriomas with a diameter greater than 10 mm, ing the passage of its tubal passage and the appear- but also in differentiating them from other adnexal ance of fluid in the bottom of the Douglas sac. Sono- masses, as well as in following their evolution under histerography is useful in differentiating endometriosis drug treatment. adenomyosis and in investigating tubal infertility, being The cystic character with homogeneous hypoechoic an alternative to hysterosalpingography. appearance, with the presence of echoes of low inten- Ultrasound remains the initial choice in the assess-