Malignant Mesothelioma, BAP1 Immunohistochemistry, and VEGFA: Does BAP1 Have Potential for Early Diagnosis and Assessment of Prognosis?

Figure 3

BAP1 immunohistochemistry. A patient presented with a pleural effusion that contained only scant mesothelial cells in an inflammatory background (a), diagnosed as reactive at the time. Only a few cells were seen in the cell block, but when this was labelled retrospectively for BAP 1, there was no labelling (b). Eight months later, cellular pleural effusion was drained from the same patient which contained papillary clusters of atypical mesothelial cells positive for calretinin (c) and showing loss of labelling for BAP1 (d). A diagnosis of atypical mesothelial proliferation was rendered. A concurrent pleural biopsy showed noninvasive papillary atypical mesothelial proliferation (e), also BAP1 negative (f) and in keeping with mesothelioma in situ.

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