15 May Proton Therapy Success with Head and Neck Cancer
Imagine a 196-ton, cancer-killing machine that can target a patient’s cancer with sub-millimeter precision while sparing nearby healthy tissues and minimizing side effects. In its most simple terms, that’s proton therapy.
Proton therapy is an advanced form of radiation treatment that delivers a powerful, highly precise beam of radiation directly to the cancer. Protons enter the body with a low radiation dose, stop at the cancer, match its shape and volume and depth, and deposit the bulk of their energy right at the cancer. The target treatment destroys cancer cells while sparing healthy tissues.
Proton therapy has a major advantage over other forms of treatment when treating vital organs such as the brain, heart, esophagus and lung. It is even more effective when treating complicated cancers of the head and neck to protect vital structures such as the eyes, mouth and brain. Patients experience fewer side effects and improved quality of life, during and after treatment.
Types of cancers treated by proton therapy
There are many types of cancers of the head and neck. Even benign tumors can cause symptoms or threaten the health and well-being of a patient. Proton Therapy may be used to treat cancers of the:
Oropharynx (tonsil and base of tongue)
Periorbital area including medial canthal tumors
Base of skull including paragangliomas/schwanommas, chordomas, chondrosaarcomas, sarcomas, squamous cell carcinoma, adenoid cystic carcinoma
Minor salivary glands
Unknown primary cancer
Reirradiation for recurrent cancers of the head and neck or new primary malignancies in a radiated field
It is important for Radiation Oncologists to work closely with a skilled multidisciplinary team to provide comprehensive care for patients who have benign or malignant tumors of the head and neck.
What to expect
Multidisciplinary care, is the hallmark feature of the approach to management of the cancer patient. When treating head and neck cancers, a diverse team of oncologists, surgeons, radiation oncologists, dental oncologist, and others with special training are needed to design a customized treatment plan.
The day of your treatment, the radiation therapist positions the patient to deliver the prescribed proton therapy dose accurately. A typical treatment session can take about 15 to 30 minutes each day for a patient with cancer of the head and neck. Most patients can tolerate the treatment and can continue to work and exercise during and immediately after treatment is complete. Proton therapy treatment is usually painless and non-invasive.
Side effects from head and neck treatment
There are different treatment options for patients who have cancer of the head and neck, which can include: surgery, radiation, chemotherapy, or any combination of the three. Each type of treatment can change the way the patient looks, talks, eats or breathes. Therefore, it is important to preserve the patient’s quality of life so they can return to their normal activities as soon as possible.
Radiation destroys the cancer cells, but it also destroys healthy cells, which can cause difficult side effects. Patients who receive radiation to the head and neck may experience:
Altered taste (dysguesia such as metallic/cardboard)
Loss of taste (aguesia)
Dry mouth (xerostomia)
Mouth ulcers (mucositis)
Pain on swallowing (odynophagia)
Difficulty swallowing (dysphagia)
Constipation (side effect of narcotics for pain management)
Also, patients may experience redness, irritation, swelling or drooping of the skin. However, any side effects that may occur during Proton therapy treatment often disappear fairly quickly once treatment is completed.
With Proton therapy, such side effects are reduced enabling patients to better maintain their weight and hydration. As a result, patients not only achieve successful treatment outcomes but substantially improve their quality of life both during and after cancer treatment.
The use of Proton therapy can help reduce the costs associated with treating these symptoms. This includes costs for:
Nutrition management (dysgeusia and weight loss)
Pain management (narcotics)
Bowel management (constipation)
Speech and swallowing (dysphagia, odynophagia and aspiration)
Hospitalization (chemistry and hematology)
Emergency center (nausea and vomiting)
Ambulatory center (IV fluids for dehydration)
Gastroenterology/Interventional Radiology (feeding tube)
One of the key components in the fight against cancer is finding the treatment option that can achieve the best clinical results. In the case of cancer of the head and neck, proton therapy reduces overall toxicity, improves quality of life during and after treatment and increases the long-term survival rate.
Cancer of the oropharynx (OPC) develops in the part of the throat just behind the mouth. OPC cancer in most cases is linked to infection with human papilloma virus (HPV) and it’s estimated that nearly 70 percent of OPC cancers are HPV-positive. A study conducted at MD Anderson Cancer Center found that the use of feeding tubes in patients being treated for oropharyngeal carcinoma (OPC) who were treated with intensity modulated proton therapy (IMPT) was decreased by more than 50 percent compared to patients treated with intensity modulated radiation therapy (IMRT). This suggests that proton therapy may offer vital quality of life benefits for patients with cancer occurring at the back of the throat. Additionally, the toxicity levels in OPC patients treated with IMPT are much lower than those treated with IMRT.
IMPT is especially well-suited for patients with the most complex cancers of the head and neck, by precisely painting the protons onto the cancer layer by layer. In this way, the treatment team can confine the majority of the cancer-damaging energy to target areas and work to protect normal structures such as the oral cavity and brainstem.
Proton therapy technology
Proton therapy has evolved and developed in a way that has not been seen before. The development of technology has been very exciting because it opens new doors that allow us to treat in a similar fashion that we are expected to treat with any other forms of radiation.
With a proton beam just millimeters wide, the advanced forms of proton therapy combine precision and effectiveness, offering unmatched ability to treat a patient’s cancer and minimizing the effect on a patient’s quality of life – during and after treatment. Proton therapy is reliant upon complex treatment planning systems and an intricate number of magnets to properly aim a narrow proton beam and essentially “paint” a radiation dose layer by layer.
Passive scattering was considered standard of care for proton beam delivery. In 2010, proton beam with active scanning became standard of care. By 2012, we were then able to do intensity modulated proton therapy (IMPT) which is the most advanced form of proton therapy delivery that allows us to treat disease sites that we were unable to do previously.
Intensity modulated proton therapy (IMPT) is best used to deliver a potent and precise dose of protons to complex or concave-shaped tumors that may be adjacent to the spinal cord or embedded into the head and neck or skull base, including nasal and sinus cavities, oral cavity, salivary glands, tongue, tonsils, and larynx. Now with the advanced form of treatment delivery proton therapy can be used in every disease site. It is a very exciting time.
We offer innovative clinical trials, which are research studies in which patients volunteer to take part. Currently, we have approximately seven open clinical trials for head and neck cancers including brain tumors. The different trials are studying the effect of higher dosages effectiveness, reirradiation, quality of life, and more. We also participate in collaborative clinical trials that span the globe.
Through our clinical trials we are developing new technologies to benefit more people with cancer. Our research base focus is defining the role of proton therapy in every disease site.
One of the things that make our center unique is that over the last years we have put out a great deal of research and publications in proton therapy, which is truly defining us as a leader in the academic radiation oncology space. With our dedicated and passionate physics team we have published more than 450 articles on the physics and outcomes of proton therapy, which have propelled the expansion of this type of radiation. In 2017, proton therapy became a standard of care radiation treatment option in the NCCN head and neck guidelines.
Our team’s breakthrough pencil-like beam technology and intensity modulated proton therapy (IMPT) have allowed us to treat a variety of cancers including brain, head and neck, prostate, lymphoma, lung and childhood tumors.
The future of treatment of cancers of the head and neck
Cancers of the head and neck can be complex and must be treated delicately, yet aggressively for effectiveness. With Proton therapy technology, the high doses of radiation necessary for treatment of the cancer can be delivered, while protecting nearby normal structures to prevent neurological deficits, intellectual impairment, blindness, and other side effects. These are some of the reasons that proton therapy has become an important tool in the treatment of cancer.
Proton therapy is the future of treatment of cancer of the head and neck. Today, there are 25 proton therapy centers operating in the United States and 10 currently under construction. Moreover, Proton therapy has become an important cancer therapy worldwide. Even countries with limited means are developing Proton therapy centers. There are 49 centers in operation worldwide including China, Japan, Italy, and Germany.
Research has demonstrated that proton therapy can maximize disease control, minimize both early and late side effects, preserve organ function and quality of life, and minimize extraneous radiation dose to the patient. As part of our commitment to the advancement of science, clinical practice, and patient outcomes, we continuously search for opportunities to communicate the value of Proton therapy to the world.
Editors Note: Dr. Frank is an endowed tenured professor of Radiation Oncology at The University of Texas MD Anderson Cancer Center, the Medical Director of MD Anderson’s Proton Therapy Center, and leader of both the Proton Therapy Program for head and neck cancer and the Prostate Brachytherapy Program. Dr. Frank also serves the Division as Director of Advanced Technologies in Radiation Oncology; he is amongst the first, if not the first, to use Intensity-Modulated Proton Therapy (IMPT) to treat head and neck tumors.
Dr. Frank is the Principal Investigator of an NIH/NCI-sponsored Phase II/III randomized trial in oropharyngeal cancer that compares outcomes after chemoradiation given by IMRT versus IMPT. His other major clinical research accomplishment includes the successful accrual of 300 patients in a Phase II protocol for prostate cancer. Dr. Frank’s expertise in MRI radiotherapy has led to the development and FDA approval of a novel positive-contrast implantable marker for use in MRI-guided prostate brachytherapy.
As founder of the company, C4 Imaging, Dr. Frank has developed the MRI marker technology at MD Anderson, currently holds 31 national and international patents and has continued MRI-Assisted Radiosurgery (MARS) at MD Anderson for the treatment of prostate cancer. He has funding from the NIH, the Prostate Cancer Foundation, the Texas Ignition Fund, Hitachi and MD Anderson, and he has also raised three rounds of private equity financing to advance C4 technology.
Dr. Frank’s expertise in prostate brachytherapy is reflected by his service as past President and Chairman of the Board of the American Brachytherapy Society. Dr. Frank’s expertise in head and neck cancer has been acknowledged by his chairing the American Board of Radiology’s Oral Examinations Program for head and neck cancer.