Researchers at the University of Texas MD Anderson Proton Therapy Center reported that the use of feeding tubes in patients with oropharyngeal carcinoma (OPC) cancer was decreased by 50% when they are treated with intensity modulated proton therapy (IMPT) instead of intensity modulated radiation therapy (IMRT). In addition, researchers found that the toxicity levels in patients treated with IMPT were much lower than those who were treated with IMRT.
OPC cancer occurs at the back of the throat, and in most cases it is linked to human papilloma virus (HPV) infection, leading to severe disease conditions. IMPT delivers a precise dose of protons to destroy only the cancerous cells, while IMRT could damage both cancerous and healthy cells. MD Anderson has treated approximately 150 OPC patients with IMPT from 2011.
“IMPT is especially well-suited for patients with the most complicated tumors of the head and neck, precisely painting the protons onto the tumor layer by layer,” said Steven J. Frank, M.D., associate professor of Radiation Oncology at MD Anderson. “In this way, the treatment team can confine the majority of the tumor-damaging energy to target areas and work to protect normal structures such as the oral cavity and brainstem.”
In the study, researchers evaluated 25 IMPT-treated patients and 25 IMRT-treated patients. 5 IMPT-treated patients (20%) required the feeding tubes, while 12 IMRT-treated patients required the feeding tubes. IMPT-treated patients did not show side effects such as vomiting, nausea, hearing problems, and mucositis, that were observed in IMRT-treated patients. In addition, IMPT-treated patients could keep better nutrition and hydration levels, often resulting in faster recovery duting and after the treatment.
“With a recent epidemic of HPV-associated head and neck cancer among U.S. adults, there is a critical need to minimize the side effects associated with conventional IMRT that affects the patients’ courses of treatments, and, ultimately, the rest of their lives,” said Frank. “Since radiation therapy is the main tool to treat the disease in this fairly young group of patients, we must understand if more advanced technologies will provide additional value to this patient population.”
MD Anderson is conducting a 5-year Phase II/III randomized trial of IMPT vs. IMRT, and aims to enroll 360 patients in the trial.
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