Proton Therapy in the Management of Luminal Gastrointestinal Cancers: Esophagus, Stomach, and Anorectum

Simple Summary Radiation treatment plays a major role in the management of luminal gastrointestinal cancers, mainly esophageal and anorectal cancers. There is a growing interest in the application of protons for gastrointestinal cancers, mainly owing to its dosimetric characteristics in decreasing dose to nearby organs at risk. We present here an up-to-date comprehensive review of the dosimetric and clinical literature on the use of proton therapy in the management of luminal gastrointestinal cancers. While the role of proton therapy in gastric cancer is marginal, its role in esophageal and anorectal cancers is expanding. In esophageal cancer, protons are superior in sparing the organs at risk, as shown by multiple dosimetric studies. Literature is conflicting regarding clinical significance, but the preponderance of evidence suggests that protons yield similar or improved oncologic outcomes to photons at a decreased toxicity cost. Similarly, protons have improved sparing of the organs at risk in anorectal cancers, but clinical data is much more limited to date, and toxicity benefits have not yet been shown clinically. Large, randomized trials are currently underway for both disease sites.

Automated summary

Radiation treatment is crucial in managing luminal gastrointestinal cancers, particularly esophageal and anorectal cancers. Proton therapy is gaining interest for its ability to decrease dose to nearby organs at risk. In esophageal cancer, protons have shown superior dosimetric characteristics in sparing organs at risk, but clinical significance is conflicting. However, evidence suggests that protons offer similar or improved oncologic outcomes with reduced toxicity compared to photons. In anorectal cancers, proton therapy has shown improved organ sparing, but clinical data is limited and toxicity benefits have not been clinically proven.