Pediatr Blood Cancer 2015;62:1514–1515
HIGHLIGHT by Sameer R. Keole,
MD*
Proton Therapy for Esthesioneuroblastoma: Can We Shed Some Light on a Murky Topic?
T
he article from Lucas et al. is a timely and valuable addition to the medical literature for two different reasons.[1] First, there is a dearth of literature related specifically to pediatric and adolescent esthesioneuroblastoma (ENB). The management approach in these patients often requires an extrapolation from adult literature. As we all know, this sometimes is not apples for apples, that is pediatric patients are not just little adults. Second, this is another article highlighting the use of proton therapy (PT) as an alternative to advanced x-ray radiation therapy (RT) techniques such as three-dimensional conformational RT or intensity-modulated RT IMRT. PT is a controversial topic, mostly because of the high cost, in terms of both installation, ongoing operational expense. PT centers, relative to x-ray RT, are significantly more expensive to build, operate.[2] As of March 2015, there are only 14 operational proton centers in the United States. It appears that nearly all PT centers treat pediatric patients, although the volumes at each center might vary. From a radiation treatment perspective, the most common questions surrounding the management of ENB in the young patient are: the role of chemotherapy, the optimal RT dose, and RT management of the neck. The majority of patients in the series from MGH did receive chemotherapy, with varying regimens described in the paper. Many chemotherapy drugs serve as radiosensitizers, which may allow for lower RT doses, but this may also lower the RT dose threshold for certain RT-related injuries, including radiation retinopathy.[3] Most commonly, radiation retinopathy is not a complication expected below mean retinal doses of 40 Gy, but in this series, two of eight patients experienced grade 2 retinopathy where the mean retinal doses were 30 CGE and 35 CGE. Both patients did receive concurrent chemotherapy. There were no grade 3þ cases of retinopathy reported. The RT dose was significantly lower in the MGH series than in many reported adult ENB series.[4] While the authors were careful not to make definitive conclusions based on the small numbers in their series, it is notable that they had 100% local control with seven of eight patients receiving
HIGHLIGHT by Sameer R. Keole,
MD*
Proton Therapy for Esthesioneuroblastoma: Can We Shed Some Light on a Murky Topic?
T
he article from Lucas et al. is a timely and valuable addition to the medical literature for two different reasons.[1] First, there is a dearth of literature related specifically to pediatric and adolescent esthesioneuroblastoma (ENB). The management approach in these patients often requires an extrapolation from adult literature. As we all know, this sometimes is not apples for apples, that is pediatric patients are not just little adults. Second, this is another article highlighting the use of proton therapy (PT) as an alternative to advanced x-ray radiation therapy (RT) techniques such as three-dimensional conformational RT or intensity-modulated RT IMRT. PT is a controversial topic, mostly because of the high cost, in terms of both installation, ongoing operational expense. PT centers, relative to x-ray RT, are significantly more expensive to build, operate.[2] As of March 2015, there are only 14 operational proton centers in the United States. It appears that nearly all PT centers treat pediatric patients, although the volumes at each center might vary. From a radiation treatment perspective, the most common questions surrounding the management of ENB in the young patient are: the role of chemotherapy, the optimal RT dose, and RT management of the neck. The majority of patients in the series from MGH did receive chemotherapy, with varying regimens described in the paper. Many chemotherapy drugs serve as radiosensitizers, which may allow for lower RT doses, but this may also lower the RT dose threshold for certain RT-related injuries, including radiation retinopathy.[3] Most commonly, radiation retinopathy is not a complication expected below mean retinal doses of 40 Gy, but in this series, two of eight patients experienced grade 2 retinopathy where the mean retinal doses were 30 CGE and 35 CGE. Both patients did receive concurrent chemotherapy. There were no grade 3þ cases of retinopathy reported. The RT dose was significantly lower in the MGH series than in many reported adult ENB series.[4] While the authors were careful not to make definitive conclusions based on the small numbers in their series, it is notable that they had 100% local control with seven of eight patients receiving
