Chris L. Hallemeier, M.D., studies the impact of radiotherapy on outcomes for patients with gastrointestinal malignancies, including cancers of the esophagus, stomach, liver, bile ducts, pancreas, intestines, rectum and anus. Dr. Hallemeier studies the integration of radiotherapy with surgery and systemic therapy to help identify optimal and individualized multimodality treatment approaches. A primary focus of his research involves proton beam radiotherapy for gastrointestinal malignancies; proton beam radiotherapy reduces radiation exposure to normal tissues and therefore may reduce short- and long-term side effects from radiotherapy.