Immunohistochemical diagnosis of epithelioid mesothelioma: an update
Tuesday, November 1st, 2005.
Archives of Pathology and Laboratory Medicine. 2005 Nov;129(11):1407-14. [Link]
Ordonez NG.
Department of Pathology, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA. nordonez@mdanderson.org
Abstract
Objective: Several new immunohistochemical markers that can assist in the diagnosis of mesotheliomas have been recognized recently. This article reviews the current information available on these markers and also provides a practical approach to the immunohistochemical diagnosis of epithelioid mesotheliomas.
Data Sources: Current literature concerning immunohistochemical markers for epithelioid mesotheliomas was collected and reviewed.
Study Selection: Literature emphasizing immunohistochemical diagnosis of epithelioid mesotheliomas was selected.
Data Extraction: Data deemed helpful to the general surgical pathologist for the diagnosis of epithelioid mesothelioma were included in this review.
Data Synthesis: Markers identified as potentially useful in the diagnosis of epithelioid mesothelioma include positive markers (namely, calretinin, keratin 5/6, D2-40, podoplanin, mesothelin, and Wilms tumor 1 protein [WT1]) and negative markers (namely, carcinoembryonic antigen, MOC-31, B72.3, and Ber-EP4). Thyroid transcription factor 1 (TTF-1) can assist in determining the lung origin of a carcinoma, and renal cell carcinoma marker (RCC Ma) may help establish its renal origin.
Conclusions: D2-40 and podoplanin are the 2 most recently recognized markers that have been found to be useful in the diagnosis of epithelioid mesotheliomas. Since D2-40 and podoplanin appear to be highly sensitive and specific for epithelioid mesotheliomas, either may be considered for inclusion in the battery of antibodies currently recommended for distinguishing epithelioid mesotheliomas from metastatic carcinomas. However, it should be kept in mind that their utility has not yet been fully determined in routine diagnostic work.
Glossary
- pathologist
- (path-all-eh-jist) a doctor who specializes in diagnosis and classification of diseases by laboratory tests (such as examination of tissue and cells under a microscope). The pathologist determines whether a lump is benign or cancerous.
- diagnosis
- identifying a disease by its signs or symptoms, and by using imaging procedures and laboratory findings. The earlier a diagnosis of cancer is made, the better the chance for long-term survival.
- cell
- the basic unit of which all living things are made. Cells replace themselves by splitting and forming new cells (mitosis). The processes that control the formation of new cells and the death of old cells are disrupted in cancer.
- carcinoma
- (car-sin-o-ma) a malignant tumor that begins in the lining layer (epithelial cells) of organs. At least 80% of all cancers are carcinomas.
- cancer
- malignancy; a group of diseases typified by abnormal, generally out-of-control, cell growth.
- antigen
- (an-tuh-jen) a substance that causes the body's immune system to react. This reaction often involves production of antibodies. For example, the immune system's response to antigens that are part of bacteria and viruses helps people resist infections. Cancer cells have certain antigens that can be found by laboratory tests. They are important in cancer diagnosis and in watching response to treatment. Other cancer cell antigens play a role in immune reactions that may help the body's resistance against cancer.
- tumor
- an abnormal lump or mass of tissue. Tumors can be benign (not cancerous) or malignant (cancerous).
- mesothelioma
- a tumor derived from mesothelial tissue, such as the peritoneum (lining the abdomen) or pleura (lining the lungs). More on mesothelioma.

