TROP-2 Immunohistochemistry as a Diagnostic Adjunct in Follicular-Patterned Thyroid Neoplasms: A Comparative Study of 100 Cases

Citra Abadi Anshar; Muhammad Husni Cangara; Tarsisia Truly Djimahit; Upik Anderiani Miskad; Djumadi Achmad; Berti Julian Nelwan; Amalia Yamin

doi:10.31557/APJCB.2026.11.4.1005

Authors

Citra Abadi Anshar Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. https://orcid.org/0009-0002-6547-5042
Muhammad Husni Cangara Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Hasanuddin University Hospital, Makassar, Indonesia. https://orcid.org/0000-0002-5160-8265
Tarsisia Truly Djimahit Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Hasanuddin University Hospital, Makassar, Indonesia.
Upik Anderiani Miskad Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Hasanuddin University Hospital, Makassar, Indonesia. https://orcid.org/0000-0002-1980-395X
Djumadi Achmad Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Hasanuddin University Hospital, Makassar, Indonesia.
Berti Julian Nelwan Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Hasanuddin University Hospital, Makassar, Indonesia. https://orcid.org/0000-0002-1999-2412
Amalia Yamin Department of Anatomical Pathology, Faculty of Medicine, Hasanuddin University, Makassar, Indonesia. Anatomical Pathology Laboratory, Dr. Wahidin Sudirohusodo Hospital, Makassar, Indonesia. https://orcid.org/0009-0008-5383-3408

DOI:

https://doi.org/10.31557/APJCB.2026.11.4.1005

Keywords:

TROP-2, thyroid neoplasm, follicular adenoma, papillary thyroid carcinoma, immunohistochemistry

Abstract

Introduction: In routine histopathological practice, thyroid neoplasms showing a follicular growth pattern often present diagnostic difficulty due to the overlapping morphological features of follicular adenoma, follicular carcinoma, and the follicular variant of papillary thyroid carcinoma. Trophoblast Cell Surface Antigen-2 (TROP-2), a transmembrane glycoprotein implicated in tumor proliferation and progression, has emerged as a potential adjunct immunohistochemical marker. This study aimed to evaluate and compare TROP-2 expression in benign and malignant thyroid neoplasms.

Methods: A cross-sectional analytical study was performed on 100 formalin-fixed, paraffin-embedded thyroid neoplasms specimens, consisting of 25 cases each of follicular adenoma (FA), follicular thyroid carcinoma (FTC), follicular variant papillary thyroid carcinoma (FVPTC), and papillary thyroid carcinoma (PTC). Immunohistochemical staining was performed using a rabbit monoclonal anti–TROP-2 antibody (clone MSVA-733R, GeneTex, GTX04443; dilution 1:200), and expression was evaluated semi-quantitatively using the H score method (range 0–300), which incorporates both staining intensity and percentage of positive tumor cells. Statistical analysis was performed using the Kruskal–Wallis test followed by the Mann–Whitney test where appropriate, with p ≤ 0.05 considered statistically significant.

Results: TROP-2 expression differed significantly among the four groups (p = 0.001). Mean H-scores were lowest in FA (57.40 ± 29.97) and progressively increased in FTC (142.16 ± 26.76), FVPTC (182.80 ± 38.41), and PTC (258.00 ± 20.92). A significant stepwise increase in H-scores was observed across the groups (FA < FTC < FVPTC < PTC), with the highest expression observed in classic PTC.

Conclusion: TROP-2 expression is significantly elevated in malignant thyroid neoplasms and may serve as a useful adjunct immunohistochemical marker in the evaluation of follicular-patterned thyroid lesions.