Tumor Treating Fields (TTFields) and Mesothelioma

How Is Tumor Treating Fields Used to Treat Mesothelioma?

Tumor Treating Fields (TTFields) is a new type of anti-cancer therapy that uses alternating electrical fields to limit cancer growth. It is combined with chemotherapy to control the growth of pleural mesothelioma. In May 2019, TTFields became the second pleural mesothelioma treatment approved by the U.S. Food and Drug Administration.

The first mesothelioma treatment approved by the FDA was a chemotherapy regimen combining Alimta (pemetrexed) with cisplatin. It was approved in 2004. TTFields is administered in combination with this chemotherapy regimen.

A company called Novocure invented the noninvasive technology. It has been developing TTFields since 2000. The FDA approved TTFields in 2011 to treat a type of brain cancer called glioblastoma. The clinical trial that led the FDA to approve TTFields for pleural mesothelioma reported an overall survival of 18.2 months.

Patients in the trial who received only chemotherapy lived 12.1 months. The addition of TTFields helped patients live an average of six months longer. TTFields doesn’t offer a cure for mesothelioma, but it can significantly improve survival with a low risk of side effects.

How Does TTFields Work?

Tumor Treating Fields applies alternating electrical fields of an intermediate frequency that are low in intensity.

Electrical fields are delivered through insulated pads that adhere to the skin. The frequency of the electrical field is 100 to 300 kilohertz, and the intensity is delivered at 1 to 3 volts per centimeter.

Research shows that applying this range of alternating frequencies to cancer cells can disrupt specific proteins essential to cell division.

When the electrical fields enter a cancer cell, they prevent these proteins from functioning correctly. This stops cancer cells from multiplying, which limits tumor growth and may kill some cancer cells.

A 2021 study published in Lung Cancer helps further explain why TTFields improves chemotherapy results. Researchers discovered that adding TTFields to chemotherapy increases the expression of proteins that damage cancer DNA and reduces the level of proteins that repair cancer DNA. Damaged cancer DNA leads to tumor cell death.

How Is TTFields Administered?

Novocure’s TTFields delivery system for mesothelioma, branded under Optune Lua (previously known as the NovoTTF-100L System), is a portable device that can be used anywhere.

The system has a TTFields-generating device, battery charger and rechargeable batteries, power supply, insulated pads and a carrying bag.

The treatment is designed for continual use at home or on the go. The carrying bag can be worn as a backpack or held in your hand.

The therapy is applied with four pads attached to the front and back of a patient’s chest. The pads are changed every two to three days, and the area must be shaved. It involves no skin incisions or inserting any medical devices into the body.

Patients are advised to wear NovoTTF-100L for 18 to 20 hours a day until their cancer progresses.

Patients can carry on with their lives while receiving treatment. They can run errands, take walks and do house chores while the therapy is administered.

However, keeping the device charged may present some logistical challenges for active people. NovoTTF-100L is plugged into a power supply or uses a large rechargeable battery pack that must be carried to power the device.

Every three weeks, patients will receive chemotherapy with Alimta and cisplatin or carboplatin for six cycles. Research shows that using NovoTTF-100L does not increase the toxicity of chemotherapy.

NovoTTF-100L is only prescribed with chemotherapy. That means patients must take chemotherapy to use the device.

Side Effects of TTFields for Mesothelioma

Skin redness and irritation are the most common side effects of TTFields therapy. Patients may also experience side effects related to the chemotherapy they receive while prescribed TTFields.

Your doctor can help you manage side effects by prescribing hydrocortisone to treat skin irritation. Severe side effects from TTFields are rare and occur in 10% or fewer patients. In these cases, your doctor will discuss with you if the benefits of TTFields outweigh the risks.

Nearly half of patients who receive the therapy report skin irritation, but only 4% report a severe level of irritation. Discuss any side effects with your health care team when you notice new or worsening issues.

Contraindications, Warnings and Precautions

TTFields therapy is not suitable for everyone, and there are specific situations where its use is contraindicated due to safety concerns. Patients with an active implanted medical device, such as a pacemaker, may not be able to use TTFields because the electromagnetic fields generated by the treatment can interfere with the function of these devices.

Some patients may be sensitive to the conductive hydrogels used to attach TTFields electrodes to the body. When the adhesive patches come into contact with the skin, severe allergic reactions, including skin irritation and potential anaphylaxis, can occur. Patients with severe skin conditions, such as infections, severe dermatitis or chest burns, may also be unsuitable candidates for TTFields.

Pregnant women or those trying to conceive should not use TTFields because the effects of electromagnetic fields on fetal development are not well understood. For safety, the NovoTTF-100L System must only be prescribed by a mesothelioma doctor who has completed the required certification training.

Research on Mesothelioma and TTFields

Research on TTFields for mesothelioma shows it can be an effective addition to standard treatments like chemotherapy, especially for those who cannot have surgery. Clinical trials have demonstrated that TTFields when used with drugs like pemetrexed and cisplatin, can improve survival rates and slow down cancer growth.

Scientists are also exploring TTFields alongside newer treatments, like immunotherapy, to see if combining these therapies can work even better. These studies help doctors refine treatment methods, make TTFields safer and determine which patients will most likely benefit. As research continues, TTFields may become an essential option for mesothelioma care, offering new hope to patients.

Availability of TTFields for Mesothelioma

As of August 2024, our research at The Mesothelioma Center shows that more than 115 cancer centers across the United States are certified to prescribe TTFields to patients with pleural mesothelioma. Many more centers are also seeking approval to offer the device.

Treatment Center	Doctors
Allegheny General Hospital	Dr. Zachary Horne Dr. Tom Colonias
Baylor College of Medicine	Dr. Pavan Jhaveri
Beaumont Hospital	Dr. Craig Stevens Dr. Zachary Seymour
Cleveland Clinic	Dr. Gregory Videtic
Frye Regional Medical Center	Dr. John O. DelCharco
Loyola University Medical Center	Dr. Tamer Abdelrhman Dr. Raymond Wynn
Miami Cancer Institute	Dr. Rupesh Kotecha
Ochsner Medical Center	Dr. Rockne Hymel Dr. Clayton Smith
Oregon Health and Science University	Dr. John Holland Dr. Josh Walker
Sylvester Comprehensive Cancer Center	Dr. Alan Dal Pra Dr. Derek Isrow
West Cancer Clinic	Dr. Matthew Ballo Dr. Cilla Edmonston Dr. Wes Garner Dr. Yuefeng Wang

In 2019, a patient at West Cancer Center in Memphis, Tennessee, became the first pleural mesothelioma patient outside of a clinical trial to use NovoTTF-100L since the FDA approved it.

“We are always looking for treatments to improve the survival, quality of life and options for patients,” said thoracic surgeon Dr. Taylor Ripley, director of the Mesothelioma Treatment Center at Baylor College of Medicine. “This provides another therapeutic option that may be valuable.”

Novocure’s other TTFields device, Optune, is specially designed to treat glioblastoma. It cannot be used to treat mesothelioma.

If you are interested in TTFields, ask your doctor if they are certified to prescribe the NovoTTF-100L System, and ask if you qualify for the therapy. The FDA has approved it only for pleural mesothelioma patients with inoperable tumors.

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