When diagnosing a patient with malignant mesothelioma, doctors determine the cell type to better understand how the disease may manifest and what the best treatment options are. There are three common cell types that compose the malignant tumors, including epithelial cells, sarcomatoid cells, and biphasic.
While epithelioid and sarcomatoid are separate mesothelioma cell types, biphasic is a combination of the two, meaning tumors of biphasic cell type contain both epithelial and sarcomatoid cells. Biphasic mesothelioma, also referred to as mixed mesothelioma, is the second most common cell type, making up around 20% - 35% of malignant pleural mesothelioma cases.
Biphasic Cell Structure
Epithelioid cells have a well-defined shape and nucleus, and are found in uniform and organized arrangements. Sarcomatoid cells are typically oval or oblong in shape, and the nucleus is not as easily recognizable.
Though biphasic tumors have a mixture of both cell types, they are typically not in the same location and form differentiated arrangements in different areas of the tumor. Multiple biopsies may be needed for an accurate diagnosis, as collecting just one cell type could lead to misdiagnosis.
In terms of metastasis, spreading is going to also depend on which cell type is dominant. If the malignant tumor has more epithelial cells, the tumor will likely spread locally. If there are more sarcomatoid cells, both local and distant spreading is common as the sarcomatoid type is more aggressive.
Diagnosing Biphasic Mesothelioma
Symptoms of any disease vary from patient to patient. Other factors, such as overall health, age, and pre-existing conditions can also affect the breadth and intensity of cancer symptoms. For biphasic mesothelioma, there are some common symptoms that can help pave the path to diagnosis.
- Shortness of breath
- Chest pain
- Tightness in the chest
- Weight loss
- Fever and/or night sweats
Biphasic mesothelioma is typically pleural-based, meaning it is located in the linings of the lungs. Malignant pleural mesothelioma is extremely aggressive and can cause an array of bothersome symptoms, not limited to those listed above.
Understanding Asbestos Exposure
In a recent study, a patient came forward with unexplained chest pain. His medical history didn't show any red flags and there weren't any other alarming symptoms that would signal a straight-forward diagnosis. However, the patient had a long history of asbestos exposure.
Currently, asbestos is the only known cause of mesothelioma, and those exposed to the substance for longer periods of time are more susceptible to developing the disease. In this case, the patient did in fact have biphasic malignant pleural mesothelioma.
Recognizing the hazards of asbestos exposure is important for those that have come in contact with the material. Oftentimes, symptoms take decades to manifest, and early detection is the main way to ensure the longest life expectancy possible.
Image Testing for Mesothelioma
Physicians use image tests to help make an accurate diagnosis, determine staging, and track tumor progression. These imaging tests include chest X-rays, CT scans, MRIs, and PET scans. Each scan provides a different type of visual, helping with various parts of the diagnostic process.
- Show bones and soft tissues
- Help identify fluid buildup, such as pleural effusion and peritoneal effusion
- Provide high-contrast, 3D visuals
- Helpful for showing the difference between tumors and healthy tissues
- Provide clear, 3D images that help differentiate cancerous tissues from healthy tissues
- Particularly helpful with staging
- Nuclear imaging technology that uses a tracer and scanning machine to observe glucose absorption
- Locates cancerous tumors against healthy tissues
- Used for staging and identifying metastasis, as well as helping determine viable treatment options
Biopsies for Biphasic Mesothelioma
After performing image testing, physicians will typically perform a biopsy to determine if a mass is cancerous or benign. This is also the only way to determine cell type, which is not apparent through imaging. Biopsies take a tissue sample of the tumor for analysis and testing. Common types of biopsies include:
- Needle biopsies
- Camera-assisted biopsies
- Surgical biopsies
Since biphasic mesothelioma has a combination of cell types, often in different regions of the tumor, multiple biopsies may be needed to recognize more than one type. It is crucial for doctors to accurately diagnose mesothelioma patients to ensure the best treatment options.
Prognosis for Biphasic Mesothelioma
The prognosis of biphasic mesothelioma is not usually straightforward and depends on the percentage of each cell type that is present in the tumor. Epithelial cells are typically more responsive to treatment than aggressive sarcomatoid cells, making biphasic tumors with a higher percentage of epithelial cells easier to address.
There are also several other characteristics that impact prognosis, such as time of detection. Early detection typically offers a more positive treatment journey, whereas late diagnosis limits a patient's options.
In comparison to epithelioid mesothelioma and sarcomatoid mesothelioma, life expectancy for the biphasic type typically falls in between the two.
|Average Life Expectancies by Mesothelioma Cell Type|
|Epithelial||12 - 24 Months|
Treatment Options for Biphasic Mesothelioma
Surgery, chemotherapy, and radiation are three common modes of treatment for mesothelioma. In addition to these traditional modes, there are also a variety of experimental treatments and clinical trials that may be an option for patients.
Surgery, Chemotherapy, and Radiation
Surgery is typically only a viable option when a tumor is detected early with the goal to remove as much of it as possible. There is no cure for mesothelioma, and metastasis can complicate the benefits of surgical removal.
Mesothelioma is commonly treated with a multimodal approach, incorporating a combination of surgery, chemotherapy, and radiation therapy. Unfortunately, biphasic mesothelioma is usually misdiagnosed and diagnosed late, often leaving palliative treatments as the most viable option.
Palliative Mesothelioma Treatments
Palliative care varies greatly and can offer numerous benefits to cancer patients. A palliative treatment plan will vary on a case-by-case basis, offering both physical and emotional comforts. The main goal of this type of care is not to focus on curing the cancer, but to focus on the comfort and well-being of the patient, eliminating as many symptoms as possible and improving quality of life.
Surgery, chemotherapy, and radiation can act as palliative treatment options for biphasic malignant mesothelioma, offering a variety of comforts, such as reducing the pressure of tumors and fluid buildup and seeking to reduce tumor size to alleviate symptoms.
- Massage therapy
- Respiratory therapy
- Occupational therapy
- Nutrition and diet planning
- Yoga and meditation
- Support groups
- Pain medication
Understanding Biphasic Mesothelioma
Every biphasic mesothelioma case is going to be different, but there are general characteristics that can help define this type of cancer.
- Second most common cell type
- Includes a mixture of sarcomatoid and epithelial cells
- Two cell types are commonly grouped in different areas of the tumor
- Early detection is uncommon
- Multimodal treatments or palliative treatments are the most common
- Usually pleural-based
- Diagnosed through image testing and biopsies
Individuals exhibiting any symptoms of mesothelioma should seek professional medical care as soon as possible. Mesothelioma is typically thought to affect only elderly individuals, though more and more cases are seen in children, young adults, and middle-aged patients. With many different types and subtypes of mesothelioma, it is crucial to find an accurate diagnosis that ensures the best treatment options for the individual affected.Sources
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