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Background Early efforts at risk-adapted therapy for neuroblastoma are predicted to result in differential late effects; the magnitude of these differences has not been well described. Methods Late mortality, subsequent malignant neoplasms (SMNs), and severe/life-threatening chronic health conditions (CHCs), graded according to CTCAE v4.03, were assessed among 5-year Childhood Cancer Survivor Study (CCSS) survivors of neuroblastoma diagnosed 1987-1999. Using age, stage at diagnosis, and treatment, survivors were classified into risk groups (low [n = 425]; intermediate [n = 252]; high [n = 245]). Standardized mortality ratios (SMRs) and standardized incidence ratios (SIRs) of SMNs were compared with matched population controls. Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals for CHC compared with 1029 CCSS siblings. Results Among survivors (49.8% male; median age = 21 years, range = 7-42; median follow-up = 19.3 years, range = 5-29.9), 80% with low-risk disease were treated with surgery alone, whereas 79.1% with high-risk disease received surgery, radiation, chemotherapy ± autologous stem cell transplant (ASCT). All-cause mortality was elevated across risk groups (SMRhigh = 27.7 [21.4-35.8]; SMRintermediate = 3.3 [1.7-6.5]; SMRlow = 2.8 [1.7-4.8]). SMN risk was increased among high- and intermediate-risk survivors (SIRhigh = 28.0 [18.5-42.3]; SIRintermediate = 3.7 [1.2-11.3]) but did not differ from the US population for survivors of low-risk disease. Compared with siblings, survivors had an increased risk of grade 3-5 CHCs, particularly among those with high-risk disease (HRhigh = 16.1 [11.2-23.2]; HRintermediate = 6.3 [3.8-10.5]; HRlow = 1.8 [1.1-3.1]). Conclusion Survivors of high-risk disease treated in the early days of risk stratification carry a markedly elevated burden of late recurrence, SMN, and organ-related multimorbidity, whereas survivors of low/intermediate-risk disease have a modest risk of late adverse outcomes. [ABSTRACT FROM AUTHOR]

PurposeThe American Society for Radiation Oncology (ASTRO) Physics Core Curriculum Subcommittee (PCCSC) has updated the recommended physics curriculum for radiation oncology resident education to improve consistency in teaching, intensity, and subject matter.Methods and materialsThe ASTRO PCCSC is composed of physicists and physicians involved in radiation oncology residency education. The PCCSC updated existing sections within the curriculum, created new sections, and attempted to provide additional clinical context to the curricular material through creation of practical clinical experiences. Finally, we reviewed the American Board of Radiology (ABR) blueprint of examination topics for correlation with this curriculum.ResultsThe new curriculum represents 56 hours of resident physics didactic education, including a 4-hour initial orientation. The committee recommends completion of this curriculum at least twice to assure both timely presentation of material and re-emphasis after clinical experience. In addition, practical clinical physics and treatment planning modules were created as a supplement to the didactic training. Major changes to the curriculum include addition of Fundamental Physics, Stereotactic Radiosurgery/Stereotactic Body Radiation Therapy, and Safety and Incidents sections, and elimination of the Radiopharmaceutical Physics and Dosimetry and Hyperthermia sections. Simulation and Treatment Verification and optional Research and Development in Radiation Oncology sections were also added. A feedback loop was established with the ABR to help assure that the physics component of the ABR radiation oncology initial certification examination remains consistent with this curriculum.ConclusionsThe ASTRO physics core curriculum for radiation oncology residents has been updated in an effort to identify the most important physics topics for preparing residents for careers in radiation oncology, to reflect changes in technology and practice since the publication of previous recommended curricula, and to provide practical training modules in clinical radiation oncology physics and treatment planning. The PCCSC is committed to keeping the curriculum current and consistent with the ABR examination blueprint.

PurposeTo measure, in the setting of typical passively scattered proton craniospinal irradiation (CSI) treatment, the secondary neutron spectra, and use these spectra to calculate dose equivalents for both internal and external neutrons delivered via a Mevion single-room compact proton system.Methods and materialsSecondary neutron spectra were measured using extended-range Bonner spheres for whole brain, upper spine, and lower spine proton fields. The detector used can discriminate neutrons over the entire range of the energy spectrum encountered in proton therapy. To separately assess internally and externally generated neutrons, each of the fields was delivered with and without a phantom. Average neutron energy, total neutron fluence, and ambient dose equivalent [H* (10)] were calculated for each spectrum. Neutron dose equivalents as a function of depth were estimated by applying published neutron depth-dose data to in-air H* (10) values.ResultsFor CSI fields, neutron spectra were similar, with a high-energy direct neutron peak, an evaporation peak, a thermal peak, and an intermediate continuum between the evaporation and thermal peaks. Neutrons in the evaporation peak made the largest contribution to dose equivalent. Internal neutrons had a very low to negligible contribution to dose equivalent compared with external neutrons, largely attributed to the measurement location being far outside the primary proton beam. Average energies ranged from 8.6 to 14.5 MeV, whereas fluences ranged from 6.91 × 10(6) to 1.04 × 10(7) n/cm(2)/Gy, and H* (10) ranged from 2.27 to 3.92 mSv/Gy.ConclusionsFor CSI treatments delivered with a Mevion single-gantry proton therapy system, we found measured neutron dose was consistent with dose equivalents reported for CSI with other proton beamlines.

Background Treatment of childhood glioma has evolved to reduce radiotherapy exposure with the goal of limiting late toxicity. However, the associations between treatment changes and neurocognition, and the contribution of neurocognition and chronic health conditions to attainment of adult independence, remain unknown. Methods Adult survivors of childhood glioma diagnosed in 1970-1999 in the Childhood Cancer Survivor Study (n = 1284; median [minimum-maximum] 30 [18-51] years of age at assessment; 22 [15-34] years from diagnosis) self-reported neurocognitive impairment and chronic health conditions. Multivariable models evaluated associations between changes in treatment exposures (surgery only, chemotherapy [with or without surgery], cranial radiation [with or without chemotherapy and/or surgery]), and neurocognitive impairment. Latent class analysis with 5 indicators (employment, independent living, assistance with routine and/or personal care needs, driver's license, marital or partner status) identified classes of functional independence. Path analysis tested associations among treatment exposures, neurocognitive impairment, chronic health conditions, and functional independence. Statistical tests were 2-sided. Results Cranial radiation exposure decreased over time (51%, 1970s; 46%, 1980s; 27%, 1990s]. However, compared with siblings, survivors with any treatment exposure were at elevated risk for neurocognitive impairment, including surgery only (eg, memory: relative risk = 2.22; task efficiency: relative risk = 1.88; both P  < .001). Three classes of functional independence were identified: independent (58%), moderately independent (20%), and nonindependent (22%). Cranial radiation was associated with nonindependence through impaired task efficiency (β = 0.06), sensorimotor (β = 0.06), and endocrine (β = 0.10) chronic health conditions and through the associations between these conditions and task efficiency (each β = 0.04). Sensorimotor and endocrine chronic health conditions were associated with nonindependence through memory. Conclusion Most long-term glioma survivors achieve adult independence. However, functional nonindependence is associated with treatment-related neurocognitive impairment and chronic health conditions. [ABSTRACT FROM AUTHOR]

Objective: To examine associations between neurologic late effects and attainment of independence in adult survivors of childhood cancer treated with central nervous system (CNS)‐directed therapies. Methods: A total of 7881 survivors treated with cranial radiation therapy (n = 4051; CRT) and/or intrathecal methotrexate (n = 4193; IT MTX) ([CNS‐treated]; median age [range] = 25.5 years [18–48]; time since diagnosis = 17.7 years [6.8–30.2]) and 8039 without CNS‐directed therapy reported neurologic conditions including stroke, seizure, neurosensory deficits, focal neurologic dysfunction, and migraines/severe headaches. Functional independence was assessed using latent class analysis with multiple indicators (independent living, assistance with routine and personal care needs, ability to work/attend school, attainment of driver's license, marital/partner status). Multivariable regression models, adjusted for age, sex, race/ethnicity, and chronic health conditions, estimated odds ratios (OR) or relative risks (RR) for associations between neurologic morbidity, functional independence, and emotional distress. Results: Among CNS‐treated survivors, three classes of independence were identified: (1) moderately independent, never married, and non‐independent living (78.7%); (2) moderately independent, unable to drive (15.6%); and (3) non‐independent (5.7%). In contrast to 50% of non‐CNS‐treated survivors and 60% of siblings, a fourth fully independent class of CNS‐treated survivors was not identified. History of stroke (OR = 2.50, 95% CI: 1.70–3.68), seizure (OR = 9.70, 95% CI: 7.37–12.8), neurosensory deficits (OR = 2.67, 95% CI: 2.16–3.31), and focal neurologic dysfunction (OR = 3.05, 95% CI: 2.40–3.88) were associated with non‐independence among CNS‐treated survivors. Non‐independence was associated with emotional distress symptoms. Interpretation: CNS‐treated survivors do not attain full independence comparable to non‐CNS‐treated survivors or siblings. Interventions to promote independence may be beneficial for survivors with treatment‐related neurological sequalae. [ABSTRACT FROM AUTHOR]