Introduction/Background Ovarian cancer (OC) is a disease associated with postmenopausal women, however, while rare, it can also profoundly impact the lives of adolescents and young people <50 years, though the clinical pathological features of this cohort are yet to be well-defined. We aimed to provide clinical and histopathology descriptive trends for OC in this population and explore potential correlative risk factors of influence associated with this disease.

Methodology Patients diagnosed with invasive OC <50 years between Mar 2005 and September 2023 were identified through the Gynaecologic Biobank at St James Hospital. Retrospective cohort study design was utilized and clinicopathological data were collected. This study was approved by the SJH/TUH Joint Research Ethics Committee Ethics Review Board.

Results 950 patients were consented to the biobank with malignant disease over this period, 140 (14.7%) were identified as invasive OC <50 years. The mean ± SD age was 40.5 years ± 8.01 years, range 16–50 years (Table 1). Most frequent histologies included serous (n=69, 49%) mucinous (n=23, 16.43%), endometrioid (n=15, 10.71%) and clear cell (n=9, 6%). Positive correlations of significance were noted between the subtype of ovarian cancer and parity (<0.001), pre-menopausal status (<0.001), height (<0.027), miscarriages (<0.009), alcohol (<0.004) (Table 2).

Conclusion We confirm that young-onset OC is a distinct entity, occurring in 14.7% of patients consented to the biobank in a tertiary referral centre over a 18-year period. We demonstrate a broad distribution of OChistologies in this age group and present parity, pre-menopausal status, height, miscarriages and alcohol intake as potential risk factors of significance. Data regarding genetic information is currently being collated and may provide further insights. While the identification of risk factors can identify high-risk patients and inform treatments, larger studies with international collaboration are essential to further define oncological risk factors in this rare disease.

Disclosures .