MIRRORS-FROZEN - Comparing Open Vs Robotic Surgery in the Management of Women with Complex Pelvic Adnexal Masses ≤ 8cm.

Open surgical staging is the current standard practice in managing women with complex adnexal masses suspicious of cancer. The diagnostic dilemma of early-stage ovarian cancer often leads to overtreatment by laparotomy in a number of patients with benign or borderline pathology.

MIRRORS-FROZEN (pilot) is a feasibility study that aims to establish whether the MIRRORS-FROZEN protocol can operate successfully and whether patients are willing to be recruited and randomized to either of the trial arms. The pilot trial also examines the feasibility and appropriateness of collecting a number of surgical, oncological, and patient-reported outcomes. The aim is to provide proof of concept that a larger, adequately powered multi-centre RCT is feasible.

Patients referred to the MDT with complex adnexal pelvic mass(es) or cyst(s) will be identified through the MDT meeting and screened against the eligibility criteria. Complex adnexal pelvic masses are defined as O-RADS-3 and deemed high risk of cancer as per subjective expert opinion, or O-RADS-4, O-RADS-5, and masses with an IOTA ADNEX score of ≥ 10%. As per standard practice, all patients referred with suspicious pelvic mass(es) will undergo a staging CT scan, serving as the primary screening tool to determine suitability for MIRRORS-FROZEN (pilot). In situations where MRI has been performed as staging imaging, the diameter of the cyst(s) or mass(es) will be used. The largest diameter of the cyst(s) or mass(es) should be ≤ 8 cm. In cases of bilateral masses or cysts, the larger cyst will be used to determine suitability for inclusion in the trial.

Potential participants will then be contacted by the trial coordinator or an appropriately trained member of the trial team to introduce the trial and provide the participant information leaflet and study consent form, along with the contact details of the trial team, at least 24 hours before the standard preoperative clinic appointment. Those who express interest in participating will undergo a comprehensive consent process conducted by an adequately trained member of the trial team. Following the consent process, baseline data collection will take place along with the baseline trial questionnaires.

All eligible participants who have consented to participate in the trial will be randomized using an online randomization service, Sealed Envelope™. Randomization will be at a ratio of 2:1 (MIRRORS-Frozen vs. standard treatment), using a simple randomization algorithm carried out by the trial coordinator/PI or a designated member of the trial team. After randomization and theatre allocation, participants will be contacted by a member of the trial team to inform participants of their allocation. No blinding or masking of allocation will occur, as both the participant and surgeon need to be aware of the allocation. The trial coordinator/PI and statistician will not be blinded to the groups.

Participants randomized to the MIRRORS-FROZEN protocol will undergo an initial laparoscopic phase. A thorough inspection of the abdomino-pelvic cavity will be performed to determine the feasibility of proceeding robotically. In patients randomized to the robotic arm and deemed suitable to proceed, peritoneal fluid or washings will be retrieved, followed by robotic excision of the mass(es) and its retrieval in a bag. The choice of specimen retrieval method, whether through a wound protector ring or vaginally, is left to the discretion of the individual surgeon. Following retrieval of the mass(es), it will be sent for frozen section analysis as per standard pathology department practice to determine the extent of the surgery.

The surgery continues robotically; however, conversion to laparotomy can be considered at any point at the discretion of the individual surgeon, in the event of surgical difficulty where it is felt to be in the patient's best interest. For example, in situations of complex adhesions or to achieve intact removal of the cyst.

Participants randomized to the open arm will start with a midline abdominal incision from the outset, with intraoperative frozen section assessment.

Frozen section results will determine the extent of surgery in both the trial arms and the following surgical steps to be performed in both trial arms: For participants with benign pathology, the surgery may either end or proceed to completion hysterectomy and removal of the remaining tube(s) and ovary(ies), based on the patient's preference and agreed consent. For participants with borderline pathology, surgical staging will be performed and includes: peritoneal biopsies of normal surfaces, including from the undersurface of the right hemidiaphragm, bladder reflection, Pouch of Douglas, right and left paracolic gutters, and both pelvic sidewalls; infracolic omentectomy; hysterectomy and contralateral salpingo-oophorectomy unless preservation of fertility is desired; and appendicectomy for mucinous tumours.

If the mass is malignant, surgical staging should include: peritoneal biopsies of normal surfaces, including from the undersurface of the right hemidiaphragm, bladder reflection, Pouch of Douglas, right and left paracolic gutters, and both pelvic sidewalls (4-6 biopsies); supracolic omentectomy; retroperitoneal lymph node assessment of pelvic and para-aortic nodes, with removal of enlarged lymph nodes as a minimum (may be omitted in mucinous tumours); hysterectomy and contralateral salpingo-oophorectomy apart from cases of apparent Stage 1A disease where fertility preservation is desired; and appendicectomy if abnormal.

The trial participants will be followed up for six weeks, and patient-reported outcome questionnaires will be collected at trial-specified points. The trial questionnaires include The European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 and the ovarian cancer module (EORTC QLQ-OV28) complementing the EORTC QLQ-C30. The Hospital Anxiety and Depression Scale (HADS), consisting of 14 items, scored on a Likert scale and 11-point pain scale (0-10), will be used. The EQ5D-5L questionnaire will also be used to collect health economic data.

All the required trial data will be recorded directly on an e-Case Record Form (eCRF) using The Research Electronic Data Capture (REDCap). The collection of Patient Reported Outcomes (PROMs) will be carried out via emails, containing a link sent to the trial participants at specific trial points. All trial appointments will be tailored around the patient's routine hospital visits, negating the need for extra visits.

Anticipating a small standardized difference and aiming to achieve 80% power for the main trial, the investigators aim to recruit 40 women within a 24-month recruitment window. This sample size is pragmatically set to provide precision in estimating predefined feasibility criteria, such as the consent rate, ensuring timely recruitment. The key feasibility parameters will be assessed, offering foundational insights for the main trial.