Plain English Summary
Comparison of intervention rates for the Risk of Malignancy Index (RMI) and the Royal College of Obstetricians and Gynaecologists green top guideline number 34 (October 2003) on postmenopausal cysts with simple ultrasound scan rules by the International Ovarian Tumour Analysis Group (IOTA): a randomised controlled trial
Most asymptomatic ovarian cysts/adnexal masses detected on ultrasound scan are benign. In these women, an operation to remove the cyst is not necessary. By avoiding surgery women are not exposed to surgical and anaesthetic complication and their care is more cost-effective. Postmenopausal women are more likely to suffer from other medical problems such as diabetes and high blood pressure, which increase operative and anaesthetic risks.
We do not expect to find a significant difference in the sensitivities for the diagnosis of ovarian cancer between the two protocols. We do expect, however, that the specificity of the new protocol will be better, which should translate into lower intervention rates.
This study hopefully will show that use of the Simple Rules and conservative management will reduce intervention rate without significantly increasing risk to the patients. This would increase patient safety and result in significant savings for the NHS.
North London Research Ethics Committee, 30/09/2010 ref: 10/H0724/48
Interventional single centre randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Asymptomatic ovarian cysts or adnexal tumours in postmenopausal women
Women with presumed benign cysts will be observed over the following year in 3-4 monthly intervals in order to detect any change in appearance or increase in size, which would be suspicious of malignancy. Any suspicion of malignant change, however, would trigger a surgical intervention.
Patients will be randomized by pulling sequential sealed envelopes. These envelopes have been prepared from a computer generated randomization list created by the statistician.
1. The Risk of Malignancy Index (RMI) and the Royal College of Obstetricians and Gynaecologists green top guideline number 34 (October 2003) on postmenopausal cysts
2. Simple ultrasound scan rules by the International Ovarian Tumour Analysis Group (IOTA)
In both arms of the study women will classified into three groups:
1. Presumed malignant cyst
2. Presumed benign cyst
3. Cysts of indeterminate nature
The management strategies will be identical in both arms:
1. Women with presumed malignancies will have surgery or management in a tertiary cancer centre
2. Women with presumed benign cysts will be managed expectantly
3. Women with indeterminate findings will be operated on in local cancer units.
Once the scan (+/- blood test) is done all assessments place patient into 1 of 3 categories. The categories are Benign, Indeterminate risk and Malignant. Those with benign tumours are offered 4 monthly scans for 1 year, those with indeterminate tumours are offered surgery in her consultants team and those with malignant tumours are referred to the tertiary oncology team.
Primary outcome measure
The number of surgical interventions in the two study groups
Secondary outcome measures
1. Number of staging laparotomies
2. Diagnostic accuracy of the two protocols
3. Number of blood tests to measure tumour markers
4. Number of surgical complications
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
1. Postmenopausal women found to have an ovarian cyst / adnexal mass
2. Postmenopausal women known to have an ovarian cyst / adnexal mass and referred for an opinion
3. Women who do not have any significant pain or bloating not explained but other pathology.
Postmenopausal women are defined as those who have had 1 year of spontaneous amenorrhoea above or at the age of 40 where no illness or medication may have caused the amenorrhoea or those above or at the age of 50 who have had a hysterectomy.
Target number of participants
Participant exclusion criteria
1. Pre-menopausal women
2. Women with pain localised to the area of the cyst or the lower abdomen
3. Women below 40 or above 80 years of age
4. Written informed consent declined or patients unable to give consent
5. Women not medically fit for surgery
6. Women with simple unilateral unilocular cysts of less than 2cm
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
University College London Hospitals
University College London Hospitals NHS Foundation Trust
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
1. 2017 results in https://www.ncbi.nlm.nih.gov/pubmed/28152542 (added 22/01/2019)