Aromatase expression in endometriotic tissues and its relationship to clinical and analytical findings.

Objective: To study the relationship between aromatase expression in endometriotic tissues and clinical and laboratory findings.

Design: Prospective basic and clinical research.

Setting: University hospital.

Patient(s): Sixty-two women with endometriosis, and 12 without endometriosis.

Intervention(s): Conservative surgery, or hysterectomy and adnexectomy, along with an immunohistochemical study of aromatase in endometriotic and nonendometriotic tissues.

Main Outcome Measure(s): Symptoms of the disease, ultrasound and surgical findings, values of tumor markers, steroids and immunoglobulins, and recurrences after surgery.

Result(s): We observed positive immunohistochemical expression for aromatase in endometriotic tissues from 38 patients (61.3%). Aromatase expression was negative in the rest of the tissues studied and in the 12 cases without endometriosis. Aromatase-positive patients had a higher number of endometriomas, more bilaterality, and more moderate-to-severe chronic pelvic pain. Also, infertility and associated leiomyomas were more frequent in these patients, though without significant differences. There were no differences in recurrence of the disease 1 year later. Estradiol and PRL levels were significantly higher, and IgG values lower, than in aromatase-negative patients. High values of blood sedimentation rate were more frequent in aromatase-negative patients.

Conclusion(s): Molecular alterations such as the presence of aromatase in endometriotic tissues could be involved in the development or maintenance of endometriosis. Our findings suggest major severity, activity, and chronic pelvic pain in patients with aromatase in endometriotic tissue.