Malignant mesothelioma is as challenging to diagnose as it is to treat. Radiologists are physicians with specialized training who play a crucial role in ensuring a prompt and accurate diagnosis. In addition to interpreting the results of imaging studies, radiologists play a key role in the staging and monitoring of mesothelioma, and interventional radiologists are increasingly involved in treating mesothelioma.
What Is a Radiologist?
Radiologists are medical doctors who specialize in the use of radiation-based imaging and treatment modalities. These are used to diagnose and treat injuries and diseases.[1]
Radiologists have specialized training that allows them to analyze and interpret the results of scans and reports, including those from the following procedures:
- Computed tomography (CT)
- Fluoroscopy
- Fusion imaging (a technique that fuses two different imaging tests)
- Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA)
- Mammography
- Nuclear medicine imaging
- Positron emission tomography (PET)
- Ultrasound
- X-rays
What Is an Interventional Radiologist?
Interventional radiologists are physicians who diagnose and treat patients using imaging technologies, including X-ray and magnetic resonance imaging, to guide them as they insert instruments into the body through tiny incisions.
These minimally invasive procedures and techniques allow interventional radiologists to reach the source of the medical problem and administer targeted tests and treatments that previously required open surgery.
Some of the procedures interventional radiologists may perform for mesothelioma patients include:[3]
- Placement of venous access devices (chest ports, tunneled and temporary central venous lines)
- Tumor embolizations (Chemoembolization, Radioembolization, Bland embolization)
- Ablation (Microwave, Radiofrequency ablation (RFA), Cryoablation, thyroid nodule RFA)
- Image-guided biopsies
- Abscess drainages
- Chest tube placements
- Thoracentesis and tunneled chest PleurX catheter placement for recurrent pleural effusions
- Paracentesis and tunneled abdominal PleurX catheter placement for recurrent ascites
How Does a Doctor Become a Radiologist/Interventional Radiologist?
All physicians begin their educational journey with a bachelor’s degree and graduation from an accredited medical school. Following graduation, candidates to become radiologists complete a four-year residency. Interventional radiologists complete a one- or two-year fellowship of specialized training.
Radiologists are certified by the American Board of Radiology and are required to fulfill extensive continuing education requirements.
Radiologists and Interventional Radiologists Diagnosing Malignant Mesothelioma
Radiologists most frequently read CT scans to diagnose mesothelioma. CT scans have become the first-line imaging technique for the diagnosis, staging, and assessment of therapy response.
Chest X-rays may also be ordered and read, but their use is limited as the technology isn’t detailed enough to allow the radiologist to distinguish between benign and malignant structures.
FDG positron emission tomography (PET) scans are used for staging the disease. MRI may become the solution to overcoming the limitations of all other scans, as radiologists can use its higher spatial resolution and soft tissue contrast to more accurately identify diaphragm and chest-wall invasion.[2]
Interventional radiologists use several minimally invasive procedures to diagnose and stage mesothelioma. Thoracocentesis is usually the first-line investigation of malignant pleural mesothelioma, though computed tomography-guided biopsy and video-assisted thoracoscopy are also effective.
For peritoneal mesothelioma, interventional radiologists are frequently asked to perform contrast-enhanced ultrasound-guided biopsies, which have proven to be a simple, safe, and accurate diagnostic method.
How Interventional Radiologists Treat Mesothelioma
Radiologists often play an important role on mesothelioma treatment teams. They can use several types of advanced radiation therapy to treat mesothelioma:
- Image-Guided Radiation Therapy (IGRT). In this type of therapy, radiologists use an imaging technique, like CT scans, to ensure treatment is highly targeted at the cancerous tissue.
- Intensity-Modulated Radiation Therapy (IMRT). IMRT uses radiation beams of varying intensities to more precisely match the shape and size of the tumor.
- Hemithoracic Radiation. This radiation therapy is specific to pleural mesothelioma. It applies the radiation to just one side of the chest to spare tissue on the other side.
- Proton Therapy. Proton therapy is a newer type of radiation therapy that uses protons, positively-charged particles, to target tumors.
One of the most exciting new malignant pleural mesothelioma treatment options being investigated is transarterial chemoperfusion
To use transarterial chemoperfusion, interventional radiologists inject a relatively high concentration of chemotherapy into the internal mammary artery that supplies the pleura as well as into the descending aorta, reaching the intercostal vessels that also supply the pleura.[4]
Similarly, interventional radiologists play an integral role in the complex surgical procedure in which patients diagnosed with malignant peritoneal mesothelioma undergo cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (HIPEC).
Radiologists and Interventional Radiologists Are Integral to the Management of Mesothelioma
Radiologists and interventional radiologists are integral members of collaborative teams of clinical experts who care for patients with mesothelioma.
The expertise is integrated with the expertise of surgical oncologists, medical oncologists, and radiation oncologists working to evaluate each case and decide the best treatment course.
