Increased levels of dioxin-like substances in adipose tissue in patients with deep infiltrating endometriosis.
OBJECTIVE
Are the levels of biologically active and the most toxic dioxin-like substances in adipose tissue of patients with deep infiltrating endometriosis (DIE) higher than in a control group without endometriosis?


CONCLUSIONS
DIE patients have higher levels of dioxins and polychlorinated biphenyls (PCBs) in adipose tissue compared with controls without endometriosis.


BACKGROUND
Some studies have investigated the levels of dioxin-like substances, in serum samples, in patients with endometriosis, with inconsistent results.


METHODS
Case-control study including two groups of patients. The study group (DIE group) consisted of 30 patients undergoing laparoscopic surgery because of DIE. In all patients, an extensive preoperative work-up was performed including clinical exploration, magnetic resonance imaging (MRI) and transvaginal sonography. All patients with DIE underwent a confirmatory histological study for DIE after surgery. The non-endometriosis control group (control group), included the next consecutive patient undergoing laparoscopic surgery in our center due to adnexal benign gynecological disease (ovarian or tubal procedures other than endometriosis) after each DIE patient, and who did not present any type of endometriosis.


METHODS
During the surgical procedure 1-2 g of adipose tissue from the omentum were obtained. Dioxin-like substances were analyzed in adipose tissue in DIE patients and controls without endometriosis.


RESULTS
The total toxic equivalence and concentrations of both dioxins and PCBs were significantly higher in patients with DIE in comparison with the control group (P < 0.05), mainly due to the significantly higher values of the two most toxic dioxins (2,3,7,8-tetrachlorodibenzo-p-dioxin [2,3,7,8-TCDD] and 1,2,3,7,8-pentachlorodibenzo-p-dioxin [1,2,3,7,8-PeCDD]) (P < 0.01 for each compound). The levels of furan 2,3,4,7,8-PeCDF were statistically higher in the DIE group compared with controls. Only four congeners of PCBs had toxic equivalence values and concentrations that were statistically higher in patients with DIE, but these included the most toxic and carcinogenic PCB-126 (PCB-114 P < 0.05; PCB-156 P < 0.05; PCB-189 P = 0.04; PCB-126 P < 0.01).


CONCLUSIONS
Since few patients were recruited, the study is only exploratory. Our results need to be confirmed in larger and more heterogeneous population studies since environmental and even genetic factors involved in determining dioxins and PCBs widely vary in different countries. Furthermore, the strict eligibility criteria used may preclude generalization of the results to other populations and the surgery-based sampling frame may induce a selection bias. Finally, adipose tissue was obtained only from the omentum, and not from other adipose tissue of the body.


CONCLUSIONS
Our results suggest a potential role of dioxin-like substances in the pathogenesis of DIE. Further studies are warranted to confirm our findings.


BACKGROUND
None.


BACKGROUND
Not applicable.
Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic of Barcelona, Faculty of Medicine, University of Barcelona, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
M A
MA
Martínez-Zamora
Laboratory of Dioxins, Deparment of Environmental Chemistry, IDAEA-CSIC, Barcelona, Spain.
L
L
Mattioli
Laboratory of Dioxins, Deparment of Environmental Chemistry, IDAEA-CSIC, Barcelona, Spain.
J
J
Parera
Laboratory of Dioxins, Deparment of Environmental Chemistry, IDAEA-CSIC, Barcelona, Spain.
E
E
Abad
Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic of Barcelona, Faculty of Medicine, University of Barcelona, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
J L
JL
Coloma
MTM Research Centre, School of Science and Technology, Örebro University, Örebro, Sweden.
B
B
van Babel
Department of Analytical Chemistry, University of Barcelona, Barcelona, Spain.
M T
MT
Galceran
Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic of Barcelona, Faculty of Medicine, University of Barcelona, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
J
J
Balasch
Institut Clínic of Gynecology, Obstetrics and Neonatology, Hospital Clínic of Barcelona, Faculty of Medicine, University of Barcelona, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain fcarmona@clinic.ub.es.
F
F
Carmona
D000273:Adipose Tissue / Q000737:chemistry*; D000293:Adolescent; D000328:Adult; D001572:Benzofurans / Q000032:analysis; D015992:Body Mass Index; D016022:Case-Control Studies; D004147:Dioxins / Q000032:analysis*; D004715:Endometriosis / Q000378:metabolism / Q000503:physiopathology*; D005260:Female; D006801:Humans; D010535:Laparoscopy; D057230:Limit of Detection; D008279:Magnetic Resonance Imaging; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D014463:Ultrasonography; D014621:Vagina / Q000000981:diagnostic imaging; D055815:Young Adult
D001572:Benzofurans; D004147:Dioxins; C023614:dibenzofuran; D011078:Polychlorinated Biphenyls; C020887:dibenzo(1,4)dioxin
adipose tissue; deep infiltrating endometriosis; dioxin-like substances; dioxins; endometriosis