Proton Beam Therapy vs Intensity-Modulated Radiation Therapy for Locally Advanced Oesophageal Cancer

3.04.2020

Radiation therapy has become an important component in the curative management of oesophageal cancer worldwide. Since most of the oesophageal cancers seen in the Western hemisphere (i.e., Europe and the United States) are located in the mid- to distal-oesophageal locations, heart and lungs invariably receive significant radiation doses. Much of the normal tissue exposure could be reduced with the utilisation of advanced radiation technologies such as intensity modulated proton therapy. Proton beam therapy (PBT) provides the ability to reduce normal tissue exposure (compared to conventional treatments) due to its lack of exit dose, which enables medical teams to provide clinically meaningful benefits to oesophageal cancer patients.

A Randomized Trial of Proton Beam Therapy Versus Intensity-Modulated Radiation Therapy for Locally Advanced oesophageal Cancer found that proton beam therapy was associated with less toxicity and similar progression-free survival vs intensity-modulated radiation therapy in patients with locally advanced oesophageal cancer.

In the trial, 145 patients were randomly assigned to proton beam therapy or intensity-modulated radiation therapy. Median follow-up was 44.1 months. The posterior mean total toxicity burden was 2.3 times higher in the intensity-modulated radiation therapy group vs the proton beam therapy group. The mean postoperative complication score was 7.6 times higher in the intensity-modulated radiation therapy group vs the proton beam therapy group (2.5, 95% highest posterior density interval = 0.3–5.2). At 3 years, overall survival was 51.2% vs 50.8% and median overall survival was 42.1 months vs 73.6 months.

The investigators concluded: “For locally advanced oesophageal cancer, proton beam therapy reduced the risk and severity of adverse events compared with intensity-modulated radiation therapy while maintaining similar progression-free survival.”

Treating oesophageal cancer with an adequate dose of radiation can be difficult because of the close proximity of the oesophagus to critical structures, such as the heart, lungs and spinal cord. Because protons deposit their highest dose of radiation at the tumor or area of concern, proton therapy can be an excellent choice for treating patients with oesophageal cancer.

Proton therapy offers patients and their doctors a unique option for effectively treating oesophageal cancer while reducing damage to other critical organs and tissues. The Prague Proton Therapy Center is one of the few centres of its kind treating oesophageal cancer with proton technology.