Cancer is a formidable diagnosis, but it is even more disconcerting when it affects a child. Radiation, a traditional therapy to treat the disease, can harm a child’s growing body, resulting in developmental delays, hormone deficiencies, and restricted bone growth. Many of the pediatric patients also experience a long-term side effect from this therapy, including secondary cancers in healthy tissues later in life.
“Any dose of radiation to a structure that is not a tumor poses a risk of a side effect,” said Avani Rao, MD, director of pediatric radiation oncology at the Inova Schar Cancer Institute. “In addition to the typical side effects from radiation that can affect any patient, children are still growing, and they can experience restrictive growth or asymmetry in developing muscle or organ tissue as a result of unnecessary exposure to radiation that does not affect adults.”
Proton therapy is a type of radiation therapy that uses protons (hydrogen ions). The proton beam can be focused to 2 millimeters (0.08 inches) to destroy the cancerous cells and prevent the tumor from spreading.
“Because you have the precision with each entry point, you need fewer beams to have a tight distribution of the dose around the target,” said Rao. “Regular radiation treatments do this by incorporating multiple beams, exposing a lot of tissue to low dose radiation to have the same effect.”
This narrow beam of radiation is delivered using a specialized machine that moves around the patient’s body to aim the beam at the tumor from many angles to match the shape and depth of the mass. In addition, the treatment can be optimized by tuning the intensity of the beam.
Once the beam reaches the tumor, it stops, focusing the maximum energy on the mass. Because the beam ends at the edge of the tumor, the tissue on the opposite side of the tumor is spared radiation exposure, lowering the harmful, long-term side effects of the treatment. It also reduces the short-term side effects, like nausea, headache, appetite loss, and diarrhea.
Inova boasts a team of over 30 medical professionals, who are trained to work with pediatric patients from the initial consultation to the final treatment. The team uses intensity modulated pencil beam proton therapy, the most advanced technology of protons today.
“I know that cancer treatment takes both a physical and an emotional toll on the patient and the family,” said Rao. “This therapy is one of the many tools I have the privilege to incorporate into my practice to minimize both the short- and long-term side effects of treatment because we are able to be as precise as possible with our cancer treatment.”
The treatment has been successfully administered to children with brain or spinal tumors, head and neck carcinoma, Hodgkin lymphoma, neuroblastoma, and sarcoma. It is also beneficial in large, irregular tumors or tumors close to critical organs or structures, like the brain, heart, lungs, and intestines, as well as the eyes, ears or mouth.
The course of treatment is tailored for each patient. It typically lasts for 15 to 30 minutes, five days a week for four to seven weeks. Most patients tolerate the treatments extremely well and can continue their normal daily routine throughout the process.
“At the end of the day, technology is technology. What matters most is the expertise of the team that knows how to use the technology in the best manner possible,” said Rao. “Working at Inova is a pleasure because I have confidence in the entire team that brings all of the steps together to create the safest radiation plan for the patient that translates in the excellent delivery of the treatment and patient experience along the way.”