PROSPECTIVE EVALUATION OF CONTRAST-ENHANCED ENDOSCOPIC ULTRASOUND AND ELASTOGRAPHY FOR DEEP PELVIC ENDOMETRIOSIS WITH BOWEL INVOLVEMENT

Aims:

Rectal endoscopic ultrasonography completes the iconographic assessment of Deep Pelvic Endometriosis (DPE) with a diagnostic sensitivity of 90% for bowel involvement. No study has evaluated the value of endoscopic ultrasound with elastography and contrast enhancement (CE-EUS) to characterize bowel lesions in DPE. The aim of this study was to characterize the bowel involvement of DPE by elastography and CE-EUS.

Methods:

This was a prospective, non-comparative, monocentric study evaluating a single group of patients, conducted from April 2015 to January 2018 at Nice University Hospital (ClinicalTrial.gov NCT03138954). Women with deep pelvic endometriosis and bowel involvement suggested beforehand by Magnetic Resonance Imaging were included. Each patient benefited from standard rectal EUS under sedation with a series of elastographic measurements and evaluation of CE-EUS (Sonovue) on bowel endometriosis's nodules.

Results:

Thirty-three patients (mean age 34.4 years [24 – 45]) with 41 bowel nodules of endometriosis were included. On the 33 nodules selected to perform the different analyses, 32 (97%) had significant contrast-enhancement. Eleven presented a hyper-enhancement (34.4%), nine an iso-enhancement (28.1%) and 12 a hypo-enhancement (37.5%). The mean elastography of the nodules, expressed as a ratio without unit, was 9.3 ± 5.2 [3.74 – 23.86]. The presence of an iso or hyper-enhancement associated with a high elastographic ratio was associated with active lesions and a better therapeutic response. Of the 11 patients with these ultrasound characteristics, 9 responded favorably symptomatically after the introduction of a hormonal treatment brake. The 2 patients who had no clinical improvement had not benefited from a specific care.

Conclusions:

EUS with elastography and CE-EUS during DPE assessment is safe and improves the characterization of bowel lesions of endometriosis. The description of active lesions (iso- or hyper-enhancement, high ratio of elastometry) could be predictive of a better response to medical treatment.