Masses in Young Patients - International Ovarian Tumour Analysis (MY-IOTA)

This multicenter observational study aims to validate the IOTA Simple Rules, Benign Descriptors, and ADNEX model in a cohort of patients equal or under the age of 20. Moreover, the study aims to evaluate the diagnostic accuracy of subjective assessment by ultrasound and to analyze the rate of complications in patients treated conservatively.

Ovarian masses are uncommon in children, with an estimated annual incidence of 2.6/100,000. They are most identified in the neonatal period or around the time of menarche. Most ovarian cysts are benign and 55-70% of which are mature cystic teratomas. In most cases, patients are asymptomatic and the ovarian lesions are incidentally detected through ultrasound examinations. However, up to 15% of cases may involve abdominal pain and torsion. Furthermore, despite the low incidence of ovarian cancer (less than 1% of all pediatric cancers), the possibility of malignant tumor must be addressed.

In 2018, a national survey of pediatric surgeons in the UK revealed significant variability in the strategies employed for investigating and surgically managing adnexal lesions in children and adolescents. Although there is a spread consensus that ultrasound indices are useful for distinguishing between benign and malignant lesions in pediatric patient, the evidence available for this specific population is limited and it lacks comprehensive data from large cohorts. Moreover, existing models developed by the International Ovarian Tumor Analysis (IOTA) group, such as the Simple Rules, Benign Descriptors, and ADNEX model, have not been validated in this younger population. Additionally, it is still unclear if these tools remain validated with a transabdominal approach, primarily used for children and non-sexually active adolescents.

The primary objective of this prospective study is therefore to assess the performance of these existing ultrasonography-based risk tools in discriminating between benign and malignant adnexal masses in neonates, young girls and adolescents using transabdominal and/or transvaginal ultrasound.

Secondary aims are the diagnostic accuracy of subjective assessment by ultrasound, the understanding of the natural history of adnexal masses at 6-8 weeks, 3 months, and 12 months and the assessment of the complications rate (such as rupture, torsion, or malignancy) in patients treated conservatively.

Final outcome will be based on pathology in patients who undergo surgery and on pattern recognition, i.e. subjective assessment of ultrasound examiner, in patients managed conservatively for masses where morphology remains unchanged during follow-up.

The study will be conducted over a minimum of two years. We anticipate recruiting 1000 surgically managed masses over a 24-month period.

Eligibility Criteria:
• Inclusion Criteria:

All newly diagnosed adnexal masses identified in a girl or adolescent aged 20 or under.

• Exclusion Criteria:

Participants eligible for this study must not meet any of the following criteria:

* Non-adnexal masses e.g. peritoneal inclusion cysts (where diagnosis is certain) and peritoneal carcinomatosis with no adnexal mass;
* The denial or withdrawal of written informed consent.
* Pregnancy at any timepoint during the study period
* In premenarchal participants: follicle measuring \<10mm