Role of FOXL2 immunohistochemical marker in diagnosis of Ovarian Sex Cord-Stromal Tumors, correlation with histopathologic features and Inhibin expression

Eman Magdi Hikal, Department of Pathology, Faculty of Medicine, Mansoura University, EgyptFollow
Sylvia Albair Ashamallah, Department of Pathology, Faculty of Medicine, Mansoura University, Egypt
Nadia Abd El-Moniem Nada, Department of Pathology, Faculty of Medicine, Mansoura University, Egypt
Dina Abdallah Ibrahim, Department of Pathology, Faculty of Medicine, Mansoura University, Egypt

Subject Area

Pathology

Article Type

Original Study

Abstract

Background: Ovarian Sex Cord-Stromal Tumors (SCST) are a broad category of rare neoplasms that exhibit diagnostic challenges. Alpha-inhibin has been traditionally used as immunohistochemical marker (IHC) for SCST, but restrictions as lack of specificity and variability of cytoplasmic staining evolved. Forkhead box L2 (FOXL2) is one of the earliest markers of ovarian differentiation and is essential for the normal development of granulosa cells and has been identified to be a sensitive and specific marker of Sex Cord-Stromal differentiation.

Aim: Assess FOXL2-IHC expression in different types of SCSTs and correlate its expression with histopathological features and Inhibin-IHC.

Methods: Retrospective study, included 60 cases of ovarian SCST, diagnosed in period from 2016 to 2023, and classified according to WHO classification (2020). Archival material was retrieved from the Surgical Pathology Laboratory of Oncology Center Mansoura University (OCMU) and Pathology Department at Faculty of Medicine, Egypt. Fifty-three cases had available paraffin blocks for performing FOXL2-IHC. Evaluation of IHC was done by a semi-quantitative system for both percentage and intensity.

Results: FOXL2-IHC expression revealed positive reaction in 96.2% of cases with higher expression in AGCTs & SLCTs, and no expression in steroid cell tumor. Strong intensity of expression observed in 100% of SLCTs cases and 53.6% of AGCTs cases. Inhibin did not consistently follow FOXL2 regarding percentage of positivity in a proportional manner, however the association between FOXL2 and Inhibin intensity was statistically significant.

Conclusion: FOXL2-IHC could be of valuable diagnostic utility in SCSTs compared to Inhibin. Being a nuclear marker that is easy to interpret and since a higher percentage of positive cells are encountered in tumors, FOXL2 can be more applicable than inhibin in routine practice.

Recommended Citation

Hikal, Eman Magdi; Ashamallah, Sylvia Albair; Nada, Nadia Abd El-Moniem; and Ibrahim, Dina Abdallah (2026) "Role of FOXL2 immunohistochemical marker in diagnosis of Ovarian Sex Cord-Stromal Tumors, correlation with histopathologic features and Inhibin expression," Mansoura Medical Journal: Vol. 55 : Iss. 4 , Article 2.
Available at: https://doi.org/10.58775/2735-3990.1549