Ascitic fluid cytology of yolk sac tumor of the ovary: a case report.

Background: Yolk sac tumor (YST) of the ovary is a rare neoplasm typically affecting children and young women. We describe the cytomorphology of this tumor in ascitic fluid and discuss its differential diagnosis from other neoplasms.

Case: Smear preparations of the ascitic fluid showed a predominance of clusters of malignant cells with vacuolated cytoplasm, mimicking a mucinous adenocarcinoma, and fewer syncytial-like and glandular structures. Hyaline globules were extremely rare. Immunocytochemistry was positive for alpha-fetoprotein.

Conclusion: The diagnosis of YST in ascitic fluid specimens may be challenging and requires the use of immunocytochemistry and the correlation of cytology with the remaining clinical and laboratory data.