Alternative radiotherapy offers less toxic treatment for children with brain tumors

Proton radiotherapy has been shown to achieve results similar to conventional photon radiotherapy while also decreasing toxicity to acceptable levels in pediatric brain tumor patients, according to results of a study published online in Lancet Oncology.

Children diagnosed with brain tumors such as medulloblastoma often suffer from debilitating effects related to treatment later in life. Recent research has suggested that proton-based radiotherapy has less harmful impact on healthy brain tissue than the currently available treatment options and could curb a substantial number of these late effects.

But the effectiveness of proton radiotherapy utilization in the treatment of pediatric brain tumor patients has yet to be fully explored, said lead author Torunn Yock, MD, and her colleagues from Massachusetts General Hospital in Boston.

“Although proton radiation therapy seems promising in terms of delivering a lower dose, many have urged caution and called for more data to better define the risks and benefits of proton radiotherapy and to show that disease control is similar to photon-based treatments,” they wrote. “For several pediatric cancers, including medulloblastoma, protons seem to be at least equivalent in attaining disease control as photon treatment.”

Yock and her team designed a trial to assess late complications, acute side-effects, and survival rates associated with proton radiotherapy in pediatric patients. To do so, they performed proton radiotheraphy on 59 children between the ages of 3–21 years who had medulloblastoma, with a median follow-up period of seven years following treatment.

They found that proton radiotherapy matched the performance of traditional photon-based therapy while reducing the impact of long-lasting late effects on the study participants.

“Our findings suggest that proton radiotherapy seems to result in an acceptable degree of toxicity and had similar survival outcomes to those achieved with photon-based radiotherapy,” the authors concluded. “Although there remain some effects of treatment on hearing, endocrine, and neurocognitive outcomes—particularly in younger patients—other late effects common in photon-treated patients, such as cardiac, pulmonary, and gastrointestinal toxic effects, were absent.”