The impact of different fixatives on immunostaining of lung adenocarcinomas in pleural effusion cell blocks.

Background: Cell blocks (CBs) are widely used for biomarker analyses such as immunostaining. Although immunohistochemistry on formalin-fixed paraffin-embedded tissues is standardized, there are multiple preparation methods and fixatives for cytology. Our objective was to investigate the effect of different common fixatives on the immunoreactivity of pleural effusion CBs with metastatic lung adenocarcinomas.

Comparison of immunohistochemical mesothelial biomarkers in paired biopsies and effusion cytology cell blocks from pleural mesothelioma.

Objective: Traditionally, the diagnosis of pleural mesothelioma is based on histological material. Minimally invasive effusion cytology specimens are an alternative that, like biopsies, require ancillary analyses. Validation of immunohistochemical (IHC) analyses on cytology, including the surrogate markers for molecular alterations BAP1 and MTAP, is of interest.