Treating Pediatric Cancers
Finding out your child has cancer can be heartbreaking. We’re here to give your child every opportunity to live a healthy, normal life. While this time can be extremely emotional, it’s important to stay as informed as possible about your treatment options. The good news is that advances in treatment methods and technology have significantly improved outcomes.
Listen to Dr. Gary Larson talk about Pediatric Cancers
The advantages of proton therapy over standard X-ray radiation
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A number of complications can result with the use of X-ray radiation therapy for pediatric brain cancer. Because the hypothalamus is close to the site of radiation, the neurohormones produced in that organ can be affected. These neurohormones stimulate the secretion of growth and thyroid hormones, which are particularly important in a growing child.1,4
Research has shown that proton therapy may significantly reduce the likelihood of developmental abnormalities, growth delays, reductions in IQ, and other complications that often occur with standard X-ray radiation.5
Protons are preferred in many pediatric cancers
Proton therapy is generally preferred for treating solid tumors in children because it delivers less radiation to normal tissues, which helps to prevent serious complications and causes fewer short- and long-term side effects.2,3 The following diagram shows the difference in radiation dose between protons and the most sophisticated form of X-ray radiation in treating a common pediatric cancer, medulloblastoma. Proton therapy delivers less radiation to the heart, lungs, abdomen and esophagus for pediatric patients with medulloblastoma. Less radiation to these critical organs reduces the likelihood that patients will experience adverse effects years after treatment.1
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Studies show that using proton therapy to control pediatric tumors provides excellent results while reducing damage to healthy tissue and reducing the likelihood of cancers occurring at other sites in the body.1,2,4
Orbital rhabdomyosarcoma (RMS) is a type of tumor that occurs in the socket (or orbit) that houses the eye. This cancer is curable 85% of the time, but the X-ray radiation needed to treat it often has long-term effects: patients frequently have reduced vision in the treated eye and some suffer a decrease in height. While the studies on treating this cancer with proton therapy are small in size, the results show great promise. In a study done at Massachusetts General Hospital, proton therapy delivered less radiation to normal tissues than X-rays, and, six years later, patients experienced fewer side effects.6,7
When Compared to Standard X-rays, Proton therapy is the safer option
Children are more prone to secondary tumors than adults, and the risk is related to the amount of tissue irradiated. Studies show that using proton therapy to control pediatric tumors provides excellent results while reducing damage to healthy tissue and reducing the likelihood of cancers occurring at other sites in the body.1,2,4 The following table shows the estimated yearly risk of a secondary tumor after a child has received treatment for medulloblastoma.2 It can be estimated from the study that even with the most sophisticated form of X-ray radiation, such as IMRT, the risk of a secondary tumor is at least 8 times greater than with proton therapy.
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What to expect when getting treated
There is no discomfort or sensation during the actual radiation treatment. Most pediatric patients have few, or very mild, side effects from proton therapy. If your child does experience any side effects, they can be managed with medications in most cases. Depending on your child’s diagnosis, treatments are usually given five days a week for a period of four to eight weeks. The time spent actually delivering the protons to the tumor is about one minute, but a pediatric cancer treatment session can range from 60 to 90 minutes, depending on the patient's needs. If sedation is required to help keep your child still during the treatment, your appointment will run on the longer side of this range. Most children are able to participate in normal activities before and after treatment.
Treatment options at a Glance
- Proton therapy – The use of proton radiation to kill cancer cells by preventing them from dividing and growing
- Standard X-ray radiation – The use of photon radiation to kill cancer cells by preventing them from dividing and growing
- Surgery – Surgical removal of tumor and affected cells
- Chemotherapy – The use of drugs to kill or alter the cancer cells
The treatment for your child will depend on the specific type of cancer he or she has. When treating pediatric cancers, a combination of treatments is often used. The good news is that advances in treatment methods and technology have significantly improved outcomes. Over 80% of childhood cancers are now curable.8
- Lee CT, Bilton SD, Famiglietti RM, et al. Treatment planning with protons for pediatric retinoblastoma, medulloblastoma, and pelvic sarcoma: how do protons compare with other conformal techniques? Int J Radiat Oncol Biol Phys. 2005;63(2):362-372.
- Miralbell R, Lomax A, Cella L, Scheider U. Potential reduction of the incidence of radiation-induced second cancers by using proton beams in the treatment of pediatric tumors. Int J Radiat Oncol Biol Phys. 2002;54(3):824-829.
- MacDonald SM, DeLaney TF, Loeffler JS. Proton Beam Radiation Therapy. Cancer Invest. 2006;(24):199-208.
- Chin D, Sklar C, Donahue B, et al. Thyroid dysfunction as a late effect in survivors of pediatric medulloblastoma/primitive neuroectodermal tumors. Cancer 1997;80(4):798-804.
- Merchant TE, Hua C, Shukla H, Ying Xiaofei, Nill S, Oelfke U. Proton versus radiotherapy for common pediatric brain tumors: comparison of models of dose characteristics and their relationship to cognitive function. Pediatr Blood Cancer. 2008;51:110-117.
- Yock T, Schneider R, Friedman A, Adams J, Fullerton B, Tarbell N. Proton radiotherapy for orbital rhabdomyosarcoma: clinical outcome and a dosimetric comparison with photons. Int J Radiat Oncol Biol Phys. 2005;63(4):1161-1168.
- Raney RB, Anderson JR, Kollath J, Vassilopoulou-Sellin R, et al. Late effects of therapy in 94 patients with localized rhabdomyosarcoma of the orbit: report from the Intergroup Rhabdomyosarcoma Study (IRS)-III, 1984-1991.
- Altekruse SF, Kosary CL, Krapcho M, et al (eds). SEER Cancer Statistics Review, 1975-2007, National Cancer Institute Web site: http://seer.cancer.gov/csr/1975_2007. Based on November 2009 SEER data submission. Published 2010.