Abstract

STUDY QUESTIONS

The objective of this study is to evaluate the effectiveness and cost-effectiveness of surgical treatment of women suffering from pain due to an ovarian endometrioma when compared to treatment with medication (analgesia and/or hormones). The primary outcome is defined as successful pain reduction (−30% reduction of pain) measured by the numeric rating scale (NRS) after 6 months. Secondary outcomes include successful pain reduction after 12 and 18 months, quality of life, affective symptoms, cost-effectiveness, recurrence rate, need of adjuvant medication after surgery, ovarian reserve, adjuvant surgery and budget impact.

WHAT IS KNOWN ALREADY

Evidence suggests that both medication and surgical treatment of an ovarian endometrioma are effective in reducing pain and improving quality of life. However, there are no randomised studies that compare surgery to treatment with medication.

STUDY DESIGN, SIZE, DURATION

This study will be performed in a research network of university and teaching hospitals in the Netherlands. A multicentre randomised controlled trial and parallel prospective cohort study in patients with an ovarian endometrioma, with the exclusion of patients with deep endometriosis, will be conducted. After obtaining informed consent, eligible patients will be randomly allocated to either treatment arm (medication or surgery) by using web-based block randomisation stratified per centre. A successful pain reduction is set at a 30% decrease on the NRS at 6 months after randomisation. Based on a power of 80% and an alpha of 5% and using a continuity correction, a sample size of 69 patients in each treatment arm is needed. Accounting for a drop-out rate of 25% (i.e. loss to follow up), we need to include 92 patients in each treatment arm, i.e. 184 in total. Simultaneously, a cohort study will be performed for eligible patients who are not willing to be randomised because of a distinct preference for one of the two treatment arms. We intend to include 100 women in each treatment arm to enable standardization by inverse probability weighting, which means 200 patients in total. The expected inclusion period is 24 months with a follow-up of 18 months.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Premenopausal women (age ≥ 18 years) with pain (dysmenorrhoea, pelvic pain or dyspareunia) and an ovarian endometrioma (cyst diameter ≥ 3 cm) who visit the outpatient clinic will make up the study population. Patients with signs of deep endometriosis will be excluded. The primary outcome is successful pain reduction, which is defined as a 30% decrease of pain on the NRS at 6 months after randomisation. Secondary outcomes include successful pain reduction after 12 and 18 months, quality of life and affective symptoms, cost-effectiveness (from a healthcare and societal perspective), number of participants needing additional surgery, need of adjuvant medication after surgery, ovarian reserve and recurrence rate of endometriomas. Measurements will be performed at baseline, 6 weeks and 6, 12 and 18 months after randomisation.

STUDY FUNDING/COMPETING INTEREST(S)

This study is funded by ZonMw, a Dutch organization for Health Research and Development, project number 80-85200-98-91041. The Department of Reproductive Medicine of the Amsterdam UMC location VUmc has received several research and educational grants from Guerbet, Merck KGaA and Ferring not related to the submitted work. B.W.J. Mol is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for ObsEva, Merck KGaA and Guerbet. V. Mijatovic reports grants from Guerbet, grants from Merck and grants from Ferring outside the submitted work. All authors declare that they have no competing interests concerning this publication.

TRIAL REGISTRATION NUMBER

Dutch Trial Register (NTR 7447, http://www.trialregister.nl).

TRIAL REGISTRATION DATE

2 January 2019

DATE OF FIRST PATIENT’S ENROLMENT

First inclusion in randomised controlled trial October 4, 2019. First inclusion in cohort May 22, 2019.

Details

Title
SOMA-trial: surgery or medication for women with an endometrioma? Study protocol for a randomised controlled trial and cohort study
Author
E van Barneveld 1 ; Veth, V B 1 ; Sampat, J M 1 ; Schreurs, A M F 2 ; M van Wely 3 ; Bosmans, J E 4 ; de Bie, B 5 ; Jansen, F W 6 ; Klinkert, E R 7 ; Nap, A W 8 ; Mol, B W J 9 ; Bongers, M Y 1 ; Mijatovic, V 2 ; Maas, J W M 10 

 Department of Obstetrics and Gynaecology, Máxima Medical Centre, Veldhoven, the Netherlands; Research School Grow, Maastricht University, Maastricht, the Netherlands 
 Department of Reproductive Medicine, Endometriosis Center, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands 
 Methodology, Department of Obstetrics and Gynaecology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam, the Netherlands 
 Department of Health Sciences, Faculty of Science, Vrije Universiteit Amsterdam, Amsterdam Public Health Research Institute, The Netherlands 
 Endometriosis Foundation of the Netherlands (Endometriose Stichting), Sittard, The Netherlands 
 Department of Obstetrics and Gynaecology, Leiden University Medical Centre, University of Leiden, Leiden, the Netherlands 
 Department of Obstetrics and Gynaecology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands 
 Department of Obstetrics and Gynaecology, Rijnstate Hospital Arnhem, Arnhem, the Netherlands 
 Department of Obstetrics and Gynaecology, Monash Medical Centre Melbourne, Melbourne, Australia 
10  Department of Obstetrics and Gynaecology, Máxima Medical Centre, Veldhoven, the Netherlands 
Publication year
2020
Publication date
2020
Publisher
Oxford University Press
e-ISSN
23993529
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3171871467
Copyright
© The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. This work is published under http://creativecommons.org/licenses/by-nc/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.