Sarcomatoid Mesothelioma Cells Explained
Sarcomatoid cells appear in 15% of mesothelioma cases, making it the least common mesothelioma cell type. These cells are most commonly found in pleural mesothelioma cases but can also appear in all other forms of mesothelioma.
Sarcomatoid cells have a poor prognosis as compared to other mesothelioma cell types. This is because their unique behaviors cause them to spread faster than other cell types. Sarcomatoid cells are also more difficult to identify because they mimic other cancer cell types.
Though sarcomatoid mesothelioma has a poor prognosis, there are encouraging examples of long-term survivors. One sarcomatoid mesothelioma patient survived seven years after a combination treatment using hyperthermia (high temperatures) and chemotherapy. This demonstrates the promising opportunities for increased survival rates because of today’s advanced mesothelioma treatments.
Sarcomatoid Cell Features
Sarcomatoid cells are elongated and fibrous with a spindle shape. Under a microscope, these cells also appear irregular and random. This distinguishes them from epithelioid cells, which appear more uniform. Sarcomatoid cells also may possess a single enlarged nucleus, multiple smaller nuclei or lack a nucleus altogether.
Sarcomatoid cells are named due to their resemblance to sarcomas, another category of malignant cancers that start in cellular linings. Often, sarcomatoid mesothelioma cells get mistaken for cells found in pulmonary sarcomatoid carcinoma, another malignant disease, due to their similar features. Sarcomatoid mesothelioma cells also closely resemble some types of healthy cells.
Sarcomatoid Cell Behaviors
Due to their different nuclei compositions, Sarcomatoid cells grow irregularly and randomly. This makes it easier for them to spread quickly throughout the body—including the bloodstream and lymph nodes. With greater mobility comes a greater risk of sarcomatoid cells metastasizing.
Sarcomatoid cells can metastasize into the renal (kidney) and hepatic (liver) areas. They can also spread to the thyroid and adrenal glands and sometimes into the brain. This is why doctors consider sarcomatoid mesothelioma cells to have the most aggressive behaviors of any other mesothelioma cell type.
Sarcomatoid Cell Subtypes
Doctors study sarcomatoid cells to help them better understand the disease, reach a diagnosis, and provide appropriate treatments. Histology is the study of cells. It is an important component of mesothelioma diagnosis as it can reveal a variety of sarcomatoid cell subtypes.
Knowing the sarcomatoid cell subtypes helps doctors give an accurate prognosis. Different subtypes each have their own unique features and behaviors.
The different sarcomatoid cell types include:
Some sarcomatoid cell subtypes are more common and others are quite rare, making some of the sarcomatoid cell subtypes are easier to identify and diagnose than others. For example, desmoplastic cells, which account for an estimated 5 percent of mesothelioma diagnoses, are difficult to identify because they have no set pattern. Transitional sarcomatoid cells are easier to identify because they appear and behave like standard sarcomatoid cells.
Sarcomatoid Mesothelioma Treatments
Because sarcomatoid cells spread quickly, they are considered difficult to treat—but sarcomatoid mesothelioma can be treated. Patients with early-stage sarcomatoid mesothelioma can undergo surgery to remove as much of the tumor as possible. Removing tumors helps to reduce painful symptoms, which improves quality of life.
However, in some cases, surgery may not be possible as sarcomatoid tumors tend to attach themselves to the chest wall. This makes it difficult for surgeons to remove the tumor and it presents health risks to the patient.
While chemotherapy isn’t usually an effective option for sarcomatoid cells, other drugs can slow down sarcomatoid cell growth. The drug combination of selenite and doxorubicin can induce apoptosis of sarcomatoid mesothelioma cells. Apoptosis occurs when cells die off. This can prevent further tumor metastasis and possibly extend life expectancy.
Palliative therapy is another important option for those with sarcomatoid mesothelioma. Palliative measures, such as radiation to shrink tumor sizes or procedures to drain pleural fluid buildup, can alleviate pain. These palliative measures help to increase patient comfort by reducing pressure in the chest and abdomen, which improves a patient’s ability to breathe.
Sarcomatoid Mesothelioma Survival Rates
At this time, the survival rate for patients with sarcomatoid mesothelioma is between four and six months after diagnosis. Roughly 10 percent of sarcomatoid mesothelioma patients survive one year after diagnosis.
While survival rates for sarcomatoid mesothelioma are the lowest of all cell types, new and emerging treatments can help improve life expectancy. Treatments for mesothelioma are constantly improving because of important clinical trials that study and advance treatments for sarcomatoid mesothelioma. Talk to your health care team about options for you to participate in mesothelioma clinical trials.