HBME-1

HBME-1 (Hector Battifora Mesothelial epitope-1) is an antibody used in immunohistochemistry, a laboratory technique that stains specific proteins in tissue samples, to help pathologists identify mesothelial cells. It is part of a panel of stains used to distinguish mesothelioma from lung adenocarcinoma and other cancers that can look similar under the microscope.

Origin

The marker was developed by pathologist Hector Battifora and colleagues in the early 1990s using an antibody raised against a membrane antigen from a human mesothelioma cell line. The exact molecular target remains incompletely characterized, but the staining pattern has proven clinically useful.

Significance in Asbestos Context

For patients, HBME-1 typically appears as one line on a pathology report among several stains (such as calretinin, WT-1, cytokeratin 5/6, D2-40/podoplanin, and negative markers like TTF-1, CEA, and MOC-31). Mesothelioma cells usually show a distinctive thick membrane ("shaggy" or surface) staining pattern with HBME-1, which helps separate mesothelioma from adenocarcinoma of the lung, a critical distinction because the two cancers have very different causes, treatments, and legal implications. Because HBME-1 can also stain some adenocarcinomas and benign mesothelial cells, it is never used alone; an accurate mesothelioma diagnosis depends on the entire immunohistochemistry panel interpreted alongside the tumor's appearance and clinical history.

Example Sentence

My pathology report listed HBME-1 as positive with a membranous staining pattern, which the pathologist explained supported the mesothelioma diagnosis along with positive calretinin and negative TTF-1.

Related Terms

Immunohistochemistry, Mesothelioma, Calretinin, Cytokeratin 5/6, WT-1, TTF-1

Notes

• Ask your oncologist or pathologist for a copy of the full immunohistochemistry panel, not just the final diagnosis, and keep it with your records; the specific markers used can become important in both treatment planning and any legal claim.
• If the diagnosis is uncertain or the panel is limited, request a second-opinion pathology review at a mesothelioma specialty center (such as an NCI-designated cancer center or a recognized mesothelioma program); misdiagnosis between mesothelioma and adenocarcinoma is well documented.
• Preserve the original tissue blocks and slides. Do not let them be discarded. They may be needed for additional staining, molecular testing (such as BAP1 or MTAP), or expert review in a legal case.
• HBME-1 staining pattern matters: a thick, membrane-bound ("shaggy") pattern favors mesothelioma, while cytoplasmic-only staining is less specific.