Palliative Radiotherapy for Mesothelioma Produces “Substantial Treatment Response”

Doctors in Pennsylvania may have found a way to boost the effectiveness of palliative radiotherapy for pleural mesothelioma.

Palliative radiotherapy is used to help with mesothelioma symptoms. It uses lower doses of radiation. Doctors do not expect to treat mesothelioma with palliative radiotherapy.

But researchers at the University of Pennsylvania think it could also be a treatment. They combined palliative radiotherapy with a special kind of gene therapy. The gene therapy affects the immune system.

They say the combination produced a “substantial treatment response” in a man with mesothelioma.

Immuno-gene Therapy and Palliative Radiotherapy

Immuno-gene therapy uses genes to stimulate the immune system against cancer. In the new Pennsylvania case study, a 67-year-old man with mesothelioma received immuno-gene therapy.

Doctors put interferon-alpha into the space around his lungs. The treatment made his own cells produce more interferon. Interferon can jumpstart the immune system to attack mesothelioma cells.

But the treatment had to stop early. The patient developed a fast heartbeat. His mesothelioma tumor also partly blocked the flow of blood to his heart.

So doctors used palliative radiotherapy instead. The man received 30 Gy of radiation during 10 treatments. Doctors hoped to shrink his mesothelioma tumor a little bit.

After radiation, he had chemotherapy with Alimta and cisplatin.

Better-Than-Expected Response

The patient’s response was even better than expected. He had a CT scan two months after he finished palliative radiotherapy. It showed a “dramatic treatment response” in the treated tumor.

But the biggest surprise was that other tumors got smaller, too. These tumors shrunk even though they were outside of the radiation treatment area. The name for this is abscopal effect.

This is the first recorded abscopal effect after palliative radiotherapy for mesothelioma. The researchers believe it is because the patient got immuno-gene therapy first.

There were a few complications. The patient’s esophagus swelled up after the radiotherapy. Doctors had to put a tube in his esophagus to keep it open until the swelling went down.

But the doctors say it is still exciting news for mesothelioma patients who can’t have surgery. It means they may have a treatment option that they did not have before.

About 2,500 Americans get malignant mesothelioma every year. Most of them had asbestos exposure at work. There is no cure for mesothelioma. Many patients die within a year of diagnosis.

Source:

Barsky, AR, et al, “First-ever Abscopal Effect after Palliative Radiotherapy and Immuno-gene Therapy for Malignant Pleural Mesothelioma”, February 2019, Cureus, https://www.cureus.com/articles/17208-first-ever-abscopal-effect-after-palliative-radiotherapy-and-immuno-gene-therapy-for-malignant-pleural-mesothelioma