Mesothelioma Cell Types
Doctors diagnose mesothelioma in two ways. One, by where it is discovered in the body, and two by examining the structure and type of cells. There are various subtypes of pleural, peritoneal, pericardial, and testicular mesothelioma based on the cells. By examining the cells doctors can identify its features to determine its cell type. The information they obtain will help better predict what the cancer’s progression will be, the likely response to treatment, and the patient’s survival time.
There are three primary types of cells: epithelial, biphasic, and sarcomatoid.
Epithelioid cells are the most common cell type in cases of mesothelioma. Patients diagnosed with an epithelioid cell type generally have the best life expectancy. It is the most treatable. It accounts for 50-70 percent of all mesothelioma cases. This cell type gets its name because it is a cancerous mutation of epithelial cells.
The Epithelioid Cell characteristics are:
• Clearly defined elongated shape
• Tendency to lump together with other epithelioid cells
• Faster tumor growth than other cell types
• Elongated nucleus
• Pink cytoplasm
• Cell type with best prognosis
Biphasic cell types are those which have both epithelioid and sarcomatoid cells present. The life expectancy of the patient is better if there are more epithelioid cells and worse if there are more sarcomatoid. The cells usually arrange in separate groups within a biphasic tumor, which is why biopsies are typically taken from different parts of the tumor. This type of mesothelioma makes up approximately 30 percent of all cases.
Sarcomatoid cells are the least common and most rare cell type accounting for only 10-15 percent of all mesothelioma cases. Sarcomatoid cells spread more quickly than epithelioid cells. This results in a shorter life expectancy and fewer treatment options. Worst prognosis for the patient.
The Sarcomatoid Cell characteristics are:
• Overlapping, irregular shape
• Enlarged, elongated nucleus (sometimes may have multiple nuclei)
• Metastasize more quickly
It is important to obtain a biopsy of the tumor to establish the cell type and confirm diagnosis. Early diagnosis is essential for improving the survival rate. Surgery may be an option if the cancer is detected soon enough. Epithelial mesotheliomas have the best survival rate while sarcomatoid cell types have the lowest.