Spotlight on pre-chemotherapy alpha-fetoprotein and survival in ovarian yolk sac tumors.

e17589 Background: Ovarian yolk sac tumor (OYST) is a rare malignancy, accounting for 20% of malignant ovarian germ cell tumors and 1% of all ovarian cancers. Primarily affecting young women and adolescents, OYSTs are highly aggressive, with rapid growth and frequent metastases. While surgery followed by cisplatin-based chemotherapy has improved outcomes, yolk sac histology remains a poor prognostic factor, with a 5-year OS rate of 69.6%. Limited data exist on prognostic factors for OYST. We aim to evaluate the prognostic value of pre chemotherapy alpha-fetoprotein (AFP) in predicting 3-year OS in patients with OYST. Methods: This retrospective cohort study utilized a database from 262 patients with malignant ovarian germ cell tumors treated at our institution from 1985 to 2020, focusing on those with a yolk sac component. The primary outcome was 3-year OS, assessed by pre chemotherapy AFP levels. Descriptive statistics summarized clinical data. ROC analysis identified the optimal AFP cutoff for 3-year OS prediction. Survival was analyzed using the Kaplan-Meier method and log-rank test, and independent prognostic factors were determined by multivariate Cox proportional hazards regression. Local research ethics board approval was obtained. Analyses were performed using SPSS Version 29.0.2 and R Version 2024.09.0+375. Results: Thirty-three patients were included, with a median age of 20 years. Stage I-II was present in 13 cases (39.4%) and advanced disease (Stage III-IV) in 20 patients (60.6%). ROC analysis demonstrated an Area Under the Curve (AUC) of 0.72 (95% CI: 0.51-0.94, p=0.04). An optimal AFP threshold of 18,000 ng/ml yielded a Youden Index of 0.53, with sensitivity at 70% and specificity at 83%. Kaplan-Meier analysis demonstrated lower 3-year OS for AFP ≥18,000 ng/mL compared to <18,000 ng/mL (36.4% vs. 90.1%, p=0.02). In multivariate analysis, AFP ≥18,000 ng/mL emerged as an independent predictor of 3-year OS (HR 4.49, 95% CI: 1.07–18.8; p=0.040), whereas FIGO stage (HR 4.84, 95% CI: 0.55–42.7; p=0.2) and chemotherapy regimen (HR 0.035, 95% CI: 0.039–1.96; p=0.13) were not statistically significant. Conclusions: Pre-chemotherapy AFP levels stratify patients with OYST into distinct risk groups for 3-year OS, with a threshold of 18,000 ng/mL serving as a prognostic marker. Despite limitations, including sample size and retrospective design, AFP's accessibility and prognostic value support its integration into clinical decision-making for this rare tumor type. Further prospective multicentric studies are warranted to validate these results.