Can BAP1 expression loss in mesothelial cells be an indicator of malignancy?
- Author:
Hanife Gulnihal OZDEMIR
1
;
Sermin Coban KOKTEN
;
Nagehan Ozdemir BARISIK
Author Information
- Publication Type:Original Article
- From:Journal of Pathology and Translational Medicine 2020;54(6):497-503
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background:Malignant mesothelioma is a highly aggressive tumor that can be confused with a benign mesothelial lesion, especially cytomorphologic lesions. BRCA1-associated protein 1 (BAP1) acts as a tumor suppressor. In this study, we aim to investigate the value of BAP1 staining of malignant mesothelioma cases with expression loss and diagnosis in cell block and biopsy tissue.
Methods:Between January 2009 and March 2017, 64 mesotheliomas, 117 reactive mesothelial hyperplasias, and 20 fibrinous pleuritis/pericarditis were diagnosed with morphologic and immunohistochemical findings in our pathology clinic and were included in the study. Formalin-fixed, paraffin-embedded tissues were immunohistochemically examined for BAP1. Inflammatory and stromal cells were used as positive internal controls. BAP1 was assessed for nuclear staining in mesothelial cells.
Results:Examinations of the relationship between patient diagnosis and BAP1 biopsy status showed that the BAP1 loss rate (76.6%) was significantly higher in malignant mesothelioma cases than in other benign diseases (0%) (p<.001). Sensitivity and specificity were 76.56% and 100%, respectively, for biopsy tissue from malignant mesothelioma. Sensitivity and specificity were both 100% for BAP1 test on cell block tissue. Furthermore, the consistency between BAP1 cell block and biopsy results was excellent (ĸ=0.90) and the correlation was significant (p<.001).
Conclusions:This study shows that BAP1 expression loss in both cytology and biopsy tissue in biopsy-confirmed malignant mesothelioma cases is an essential parameter for malignant mesothelioma diagnosis.
