Objectives: Fine-needle aspiration (FNA) of ovarian cyst fluid remains useful for certain clinical circumstances despite low sensitivity and potential safety concerns. The current study aimed to reevaluate the performance of ovarian cystic fluid cytology following American College of Obstetricians and Gynecologists guidelines using a single-institution cohort.

Methods: A total of 507 ovarian cyst FNA cases from 2013 to 2023 were reviewed. Patients' demographics and clinical and radiologic information were collected through the electronic database. The performance was calculated using corresponding surgical pathology diagnosis as the gold standard.

Results: Overall, cytologic diagnoses were nondiagnostic (ND), negative for malignancy (NFM), atypical (ATY), suspicious for malignancy (SFM), and malignant (M) in 5 (1.0%), 478 (94.3%), 14 (2.7%), 2 (0.4%), and 8 (1.6%) cases, respectively. Among 349 specimens (68.8%) that had a corresponding surgical pathology, the rate of malignancy (including borderline tumors) was 1.2% (4 of 325) in NFM, 72.7% in ATY (8 of 11), and 100% in both SFM (2 of 2) and M (8 of 8) specimens. Considering NFM and ATY as negative results and SFM and M as positive results, overall, the sensitivity of ovarian cystic fluid cytology was 45.4% and the specificity was 100%.

Conclusions: As an uncommon test, ovarian cystic fluid cytology has moderate sensitivity and high specificity. Despite limitations, ovarian cystic FNA cytology remains a valuable diagnostic tool in certain aspects.