Identifying the best diagnostic test for ovarian cancer - synopsis of Refining Ovarian Cancer Test accuracy Scores (ROCkeTS) research.

[BACKGROUND] Ovarian cancer survival is stage-dependent: Stage I patients have 90% 5-year survival versus 15% for stage IV. Over 70% of patients worldwide are diagnosed at advanced stages. Ovarian cancer presents with non-specific symptoms (abdominal bloating, early satiety, discomfort/pain, bowel/urinary changes). Current National Institute for Health and Care Excellence guidelines recommend that symptomatic women presenting to primary care are tested with cancer antigen 125 and ultrasound, then referred to secondary care for further triage if these tests are abnormal. Current standard of care risk prediction model used to triage women in National Health Service secondary care is Risk of Malignancy Index 1 combining cancer antigen 125 and simple ultrasound features, which at 250 threshold has 70% sensitivity and 90% specificity. Newer models offer potential for improved sensitivity, earlier diagnosis and better survival outcomes.

[OBJECTIVES] To evaluate diagnostic strategies for ovarian cancer in women with non-specific symptoms through systematic review, United Kingdom Collaborative Trial of Ovarian Cancer Screening data set analysis, prospective studies and health economic evaluation comparing Risk of Malignancy Index 1 against newer approaches including Risk of Ovarian Malignancy Algorithm, Ovarian-Adnexal Reporting and Data System and International Ovarian Tumour Analysis models, including International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa.

[METHODS] Four concurrent work packages: (1) Cochrane systematic review; (2) United Kingdom Collaborative Trial of Ovarian Cancer Screening data set model development; (3) prospective multicentre diagnostic accuracy study (ROCkeTS) with parallel pre/postmenopausal cohorts; and (4) cost-consequence analysis. Allied analyses investigated psychological impact and cancer outcomes from symptom-triggered pathways. ROCkeTS recruited 2453 women across 23 hospitals (2015-23) with symptoms, raised cancer antigen 125 and/or abnormal imaging. Women completed questionnaires, donated blood and underwent transvaginal ultrasound scored by International Ovarian Tumour Analysis terminology by certified National Health Service sonographers with quality assurance. Reference standard was histology for surgical cases or 12-month wellbeing ascertainment. Primary outcome: primary invasive ovarian cancer versus benign or normal.

[RESULTS] The Cochrane systematic review (58 studies, 30,121 patients and 9061 ovarian cancer cases) demonstrated that most published diagnostic test accuracy studies failed to differentiate between pre- and postmenopausal women, and all were conducted in high-prevalence settings, limiting applicability to routine practice. In the ROCkeTS prospective study in premenopausal women, in the initial cohort recruited prior to protocol change ( = 857), Risk of Malignancy Index 1 at threshold 250 showed poor sensitivity (42.6%, 95% confidence interval 28.3 to 57.8) but high specificity (96.5%, 95% confidence interval 94.7 to 97.8). All other tests improved sensitivity but dropped specificity. International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa at 10% threshold achieved significantly higher sensitivity (89.1%, 95% confidence interval 76.4 to 96.4), higher than all other tests with acceptable specificity (73.2%, 95% confidence interval 69.9 to 76.4). In the ROCkeTS prospective cohort study in postmenopausal women ( = 1242), Risk of Malignancy Index 1 at 250 demonstrated better performance (82.9%, 95% confidence interval 76.7 to 88.0), but International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa at 10% had the best sensitivity at 96.1% (95% confidence interval 92.2 to 98.4) compared to Risk of Malignancy Index 1 with the least drop of specificity. Risk of Ovarian Malignancy Algorithm at manufacturer recommended threshold and Ovarian-Adnexal Reporting and Data System did not improve on Risk of Malignancy Index 1 sensitivity in postmenopausal women. Cancer prevalence differed between premenopausal (5.7%) and postmenopausal (17%) cohorts. Early-stage cancer (I/II) were diagnosed in 60.2% of premenopausal and 41% of postmenopausal cohorts. Cancer diagnosis rates were very low (1.6%) in women under 40 years. High anxiety and distress were noted, particularly in younger women. One in four women with high-grade serous ovarian cancers were diagnosed at early stage (I/II). Complete cytoreduction was achieved in 61.3% of cases, with optimal cytoreduction (≤ 1 cm residual disease) in an additional 15.1%. Cost-consequence analysis demonstrated that a two-step strategy deployed at the same ultrasound sitting, initially triaging out benign looking tumours on ultrasound, then calculating ovarian cancer risk with International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa ultrasound model at 10% demonstrated the best balance across cost, diagnostic yield and cancer deaths compared to other diagnostic strategies.

[LIMITATIONS] Cohort study required key changes to protocol and post-pandemic recruitment was slow.

[CONCLUSIONS] International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa ultrasound at 10% threshold, delivered by trained National Health Service sonographers demonstrated superior diagnostic performance compared to Risk of Malignancy Index 1 and should be considered as new standard of care for suspected ovarian cancer in pre- and postmenopausal women. A two-step strategy using International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa offers optimal balance across cost, diagnostic yield and cancer death reduction. Implementation requires sonographer training investment and quality assurance.

[FUTURE RESEARCH] International Ovarian Tumour Analysis Assessment of Different NEoplasias in the adneXa implementation in primary care/community settings, artificial intelligence-enabled quality assurance, reconfiguration of referral pathways in primary care to reduce unnecessary referrals in younger women and consequent harm are important research areas. Systematic symptom elicitation capitalising on routine health interactions to reach underserved communities warrants further research.

[FUNDING] This synopsis presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number 13/13/01.