Roche has announced the global launch of the VENTANA BAP1 test, an automated immunohistochemistry (IHC) assay designed to help pathologists identify malignant mesothelioma and distinguish it from other cancers, including Non-Small Cell Lung Cancer (NSCLC). The assay is registered as a Class I in Vitro Diagnostic (IVD) with the US Food and Drug Administration (FDA), has received approval as a Class C device under the European Union’s In Vitro Diagnostic Regulation (IVDR), and is available globally.

Mesothelioma is a rare cancer that develops in the tissue lining several internal organs. More than 80 percent of cases affect the pleura, the tissue surrounding the lungs. Accurate diagnosis is important for distinguishing malignant mesothelioma from other malignancies and benign conditions that may present with similar features.

Matt Sause, CEO of Roche Diagnostics, said timely differential diagnosis is important for patient outcomes. He added that the launch of the BAP1 assay expands Roche’s diagnostic portfolio for diseases such as mesothelioma, where significant unmet clinical needs remain.

The VENTANA BAP1 (SP527) Rabbit Monoclonal Primary Antibody is designed for automated IHC testing to detect the loss of nuclear expression of BAP1, a tumour suppressor protein associated with the chromosome 3p21 region. Loss of nuclear BAP1 expression is highly specific for malignancy in mesothelial proliferations and can help confirm a diagnosis of mesothelioma when used alongside mesothelial lineage markers such as WT1 and calretinin.

Preserving limited tissue samples is a key challenge in diagnosing lung cancer and mesothelioma. Conventional diagnostic approaches may require multiple antibody tests, potentially exhausting tissue samples needed for further analysis. Highly specific markers such as BAP1 (SP527), together with Roche’s VENTANA MTAP (SP530) and VENTANA Claudin-4 (EP417) assays, can help pathologists differentiate between malignancies while limiting tissue use.

Preserving tissue is particularly important because additional molecular testing may be required to guide treatment decisions. By supporting more efficient sample management, these assays can help retain tissue for molecular sequencing and other precision medicine tests.

Lung cancer remains the leading cause of cancer-related deaths worldwide, with more than 2.5 million people diagnosed annually. Non-small cell lung cancer accounts for up to 85 percent of lung cancer cases, according to the information provided by Roche.

Roche’s lung cancer diagnostics portfolio includes tissue-based tests, immunohistochemistry assays, molecular diagnostics and digital software. Its offerings include haematoxylin and eosin (H&E) staining and IHC assays for ALK (D5F3), PD-L1 (SP263) and MET (SP44), alongside oncology polymerase chain reaction (PCR), comprehensive genomic profiling and next-generation sequencing (NGS) solutions, and navify digital software.

The addition of the VENTANA BAP1 assay to the company’s existing diagnostic portfolio is intended to support the differentiation of malignant mesothelioma from benign and metastatic conditions that may resemble it. Used alongside the MTAP and Claudin-4 assays, BAP1 can contribute to diagnostic assessment while helping preserve tissue for further testing.