Mesothelioma Cancer Cell Types
In this poignant opening, we describe the broad scope of the upcoming text on the rest of page, which describes that various types of mesothelioma cells and provides a platform from which to dive into the additional information provided about each cell type.
Epithelioid Mesothelioma
Epithelioid mesothelioma is the most common type of malignant mesothelioma cell type, accounting for 50-70% of all mesotheliomas. Individual cells are known to be relatively uniform in shape and with a uniquely “tubular” appearance. When the cell is viewed under intense magnification, the cell nuclei is known to be distinctly distinguishable from other cell nuclei.
Other cancer cell types, such as adenocarcinomas, however, have been known to take similar shape and are often misclassified. Adenocarcinomas are cancer cells that can also occur within the mesothelium, but cannot originate within this membrane. Typically adenocarcinomas will originate within more internal tissue before surfacing within the mesothelium.
Biphasic Mesothelioma
Biphasic mesothelioma refers to a cell structure associated with malignant mesothelioma tumor cells. Among mesothelioma cancer cells, they are generally divided into two subcategories. Epithelioid mesothelioma cells are the most common type, accounting for approximately 80% of all malignant mesothelioma cells. Sarcomatoid mesothelioma cells are far rarer, accounting for just 10-15% of malignant mesothelioma cells. Biphasic mesothelioma cancers are those which comprise a combination of the two aforementioned malignant cells types.
Epithelioid mesothelioma malignant cells have a clearly defined tubular structure. Upon intense magnification, the cell structure is clearly visible, including a distinguishable nucleus. Sarcomatoid mesothelioma malignant cells are clearly different than epithelioid cells, with their oval shape being clearly distinguishable from their counterpart. Upon intense magnification, the cell structure is loosely visible while the nucleus is often muddled and difficult to distinguish.
Papillary Mesothelioma
Papillary mesothelioma is better and more commonly referred to among the medical establishment as well-differentiated papillary mesothelioma, or WDPM. Papillary mesothelioma, unlike other mesotheliomas, is generally considered to be of low malignant potential. Papillary mesothelioma is also likely to stay localized and not spread to other areas of the body outside of its origin.
Treatment for papillary mesothelioma is not standardized, as this particular type of mesothelioma is extraordinarily rare. Surgery is typically recognized as the preferred treatment and is often available to patients diagnosed with papillary mesothelioma. Other treatments include several types of chemotherapy, including those used for traditional mesothelioma tumors.
This particular mesothelioma is not associated with any particular symptoms. The disease is classified as clinically indolent, meaning there is relatively no pain or discomfort associated with the mesothelioma and the tumor is relatively inactive. Those diagnosed with papillary mesothelioma are typically expected to make a complete recovery and prognosis is positive across the board. The most common papillary mesothelioma tumors form within the peritoneum (membrane which surrounds the abdominal cavity) in women of reproductive age. Other cases have been documented as originating in the lining of the heart and lungs.
Unlike malignant mesotheliomas, which are typically associated with asbestos exposure, there is no conclusive evidence ing papillary mesothelioma to asbestos exposure and those diagnosed with papillary mesothelioma will often have no asbestos history of significance.
Sarcomatoid Mesothelioma
Sarcomatoid mesothelioma is a rare malignant cell type and only accounts for between 10-15% of all mesothelioma cancer cells. This is least common type of mesothelioma. Sarcomatoid mesothelioma cells are oval shaped, but consistently irregular and not as uniform as epithelioid mesothelioma cells. The nucleus of sarcomatoid cells, so clear and distinguishable in epithelioid cells of the same type, is muddled and not as visible.
The oval shape of the sarcomatoid mesothelioma cells is common in other cell structures, and while it is not often associated with mesothelioma, they can closely mimic those of other malignancies, including those of sarcomatoid carcinoma and sarcoma. While sarcomatoid mesothelioma cells can manifest in other parts of the body, there are relatively rare within the lungs (the origin of most mesothelioma malignancies).
Pulmonary sarcomatoid carcinoma is that carcinoma most closely mimics sarcomatoid mesothelioma. Symptoms of both cell type also parallel, including chest pains, effusions of the chest and abdomen, and difficulty breathing.
Butnor, K., Sporn, T., Hammar, S. et al. Well-Differentiated Papillary Mesothelioma. (2001). The American Journal of Surgical Pathology: 1304-1309.
Spano, J., Soria, J., Sabourin J. Well-Differentiated Papillary Mesothelioma (WDPM): Successful therapy by local surgery alone or combined with intraoperative intraperitoneal heated chemotherapy (IPHC) perfusion using cisplatin. (2003). Proceeding of the American Society for Clinical Oncology; 22.
https://www.maacenter.org/mesothelioma/types/mesothelioma-cell-types/
