Median hypothalamic and pituitary radiation dose, younger age, and longer follow-up time were associated with increased rates of endocrinopathy in children and young adults treated with radiotherapy for brain tumors.
Purpose/Objective(s)
To compare long-term disease control and overall survival between children treated with proton and photon radiotherapy (RT) for standard risk medulloblastoma.
Methods and Materials
This multi-institution cohort study includes 88 children treated with chemotherapy and proton (n=45) or photon (n=43) RT between 2000 and 2009. Overall survival (OS), recurrence-free survival (RFS) and patterns of failure were compared among the two cohorts.
Results
Median (range) age at diagnosis was 6 yrs (3 - 21) for proton pts vs. 8 yrs (3 -19) for photon pts (p=0.011). Cohorts were similar with respect to gender, histology, extent of surgical resection, craniospinal (CSI) RT dose, total RT dose, whether the RT boost was delivered to the posterior fossa (PF) or tumor bed (TB), time from surgery to RT start, or total duration of RT. RT consisted of a median (range) CSI dose of 23.4 Gy (18 - 27) and a boost of 30.6 Gy (27 - 37.8). Median (95% CI) f/up time is 6.2 yrs (5.1 – 6.6) for proton pts vs. 7.0 yrs (5.8 – 8.9) for photon pts. There was no significant difference in RFS or OS between pts treated with proton vs. photon RT: 6 yr RFS 78.8% vs. 76.5% (p=0.948) and 6 yr OS 82.0 vs. 87.6% (p=0.285). On multivariable analysis, there was a trend for longer RFS with female gender (p=0.058) and higher CSI dose (p=0.096), and for longer OS with female gender (p=0.093). Patterns of failure were similar among the two cohorts (p=0.908).
Conclusions
Disease control with proton and photon radiotherapy appears equivalent for standard risk medulloblastoma.
BACKGROUND:Proton therapy may reduce cognitive deficits after radiotherapy among brain tumor survivors, although current data are limited to retrospective comparisons between historical cohorts. The authors compared intelligence quotient scores within a casematched cohort of children with medulloblastoma treated with proton radiation (PRT) or photon radiation (XRT) over the same time period. METHODS: Among 88 consecutive patients with standard-risk medulloblastoma treated with PRT or XRT at 2 institutions from 2000 to 2009, 50 were matched 1:1 (25 with PRT and 25 with XRT) according to age, gender, date of diagnosis, histology, radiation boost, and craniospinal irradiation dose. One-way analyses of variance were performed to compare the Full-Scale Intelligence Quotient (FSIQ) and associated index scores between the 2 cohorts. RESULTS: Neurocognitive data were available for 37 survivors (17 with PRT and 20 with XRT) from the matched cohort. The mean age was 8.5 years (SD, 4.14 years). The median follow-up was 5.3 years (range, 1.0-11.4 years) and 4.6 years (range, 1.1-11.2 years) for the PRT and XRT cohorts, respectively (P = .193). Patients treated with PRT had significantly higher mean FSIQ (99.6 vs 86.2; P = .021), verbal (105.2 vs 88.6; P = .010), and nonverbal scores (103.1 vs 88.9; P = .011) than the XRT-treated cohort. Differences in processing speed (82.9 vs 77.2; P = .331) and working memory (97.0 vs 92.7; P = .388) were not statistically significant. CONCLUSIONS: Radiotherapy-associated cognitive effects appear to be more attenuated after proton therapy. Comprehensive prospective studies are needed to appropriately evaluate the neurocognitive advantages of proton therapy. Cancer 2021;127:3840-3846.
Background/objectivesThe Pediatric Proton Consortium Registry (PPCR) was established to expedite proton outcomes research in the pediatric population requiring radiotherapy. Here, we introduce the PPCR as a resource to the oncology community and provide an overview of the data available for further study and collaboration.Design/methodsA multi-institutional registry of integrated clinical, dosimetric, radiographic, and patient-reported data for patients undergoing proton radiation therapy was conceived in May 2010. Massachusetts General Hospital began enrollment in July of 2012. Subsequently, 12 other institutions joined the PPCR and activated patient accrual, with the latest joining in 2017. An optional patient-reported quality of life (QoL) survey is currently implemented at six institutions. Baseline health status, symptoms, medications, neurocognitive status, audiogram findings, and neuroendocrine testing are collected. Treatment details of surgery, chemotherapy, and radiation therapy are documented and radiation plans are archived. Follow-up is collected annually. Data were analyzed 25 September, 2017.ResultsA total of 1,854 patients have consented and enrolled in the PPCR from October 2012 until September 2017. The cohort is 55% male, 70% Caucasian, and comprised of 79% United States residents. Central nervous system (CNS) tumors comprise 61% of the cohort. The most common CNS histologies are as follows: medulloblastoma (n = 276), ependymoma (n = 214), glioma/astrocytoma (n = 195), craniopharyngioma (n = 153), and germ cell tumors (n = 108). The most common non-CNS tumors diagnoses are as follows: rhabdomyosarcoma (n = 191), Ewing sarcoma (n = 105), Hodgkin lymphoma (n = 66), and neuroblastoma (n = 55). The median follow-up is 1.5 years with a range of 0.14 to 4.6 years.ConclusionA large prospective population of children irradiated with proton therapy has reached a critical milestone to facilitate long-awaited clinical outcomes research in the modern era. This is an important resource for investigators both in the consortium and for those who wish to access the data for academic research pursuits.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.