Tumor bed proton irradiation in young children with localized medulloblastoma

The effectiveness and safety of proton beam radiation therapy in children and young adults with Central Nervous System (CNS) tumours: a systematic review

BACKGROUND

Central nervous system (CNS) tumours account for around 25% of childhood neoplasms. With multi-modal therapy, 5-year survival is at around 75% in the UK. Conventional photon radiotherapy has made significant contributions to survival, but can be associated with long-term side effects. Proton beam radiotherapy (PBT) reduces the volume of irradiated tissue outside the tumour target volume which may potentially reduce toxicity. Our aim was to assess the effectiveness and safety of PBT and make recommendations for future research for this evolving treatment.

METHODS

A systematic review assessing the effects of PBT for treating CNS tumours in children/young adults was undertaken using methods recommended by Cochrane and reported using PRISMA guidelines. Any study design was included where clinical and toxicity outcomes were reported. Searches were to May 2021, with a narrative synthesis employed.

RESULTS

Thirty-one case series studies involving 1731 patients from 10 PBT centres were included. Eleven studies involved children with medulloblastoma / primitive neuroectodermal tumours (n = 712), five ependymoma (n = 398), four atypical teratoid/rhabdoid tumour (n = 72), six craniopharyngioma (n = 272), three low-grade gliomas (n = 233), one germ cell tumours (n = 22) and one pineoblastoma (n = 22). Clinical outcomes were the most frequently reported with overall survival values ranging from 100 to 28% depending on the tumour type. Endocrine outcomes were the most frequently reported toxicity outcomes with quality of life the least reported.

CONCLUSIONS

This review highlights areas of uncertainty in this research area. A well-defined, well-funded research agenda is needed to best maximise the potential of PBT.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO-CRD42016036802.

Psychometric validation of the simplified Chinese version of the therapy-related symptom checklist in children with cancer

PURPOSE

To validate a simplified Chinese version of the therapy-related symptom checklist for children (TRSC-C) in children with cancer.

METHODS

Reliability was assessed by internal consistency and test-retest coefficients. Dimensionality and construct validity were clarified using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Pearson's correlation coefficient was calculated between the TRSC-C and the PedsQL 3.0 cancer model (PedsQL 3.0) and the Lansky Play Performance Scale (LPPS) to test concurrent validity. A Student's t-test was used to compare the scores of the simplified Chinese version of the TRSC-C subscales by gender, age groups, and functional status to test sensitivity of the TRSC-C.

RESULTS

A sample of 170 children with cancer was recruited (11.27 ± 2.31 years). Cronbach's alpha (0.89) and interclass correlation coefficient (0.98) were acceptable. Seven factors with eigenvalues >1 explained 56.86% of the total variances. CFA demonstrated an acceptable model (CFI = 0.93, RMSE = 0.04). Concurrent validity was supported by moderate to high correlations between the TRSC-C and both the PedsQL 3.0 (r = -0.71) and LPPS (r = -0.43). The TRSC-C scores significantly differed by age groups and functional status (effect size 0.40-0.93), indicating adequate sensitivity.

CONCLUSION

The simplified Chinese version of the TRSC-C demonstrated acceptable reliability, validity, and sensitivity to support its use in clinical practice and future studies.

Patients, caregivers, and clinicians differ in performance status ratings: Implications for pediatric cancer clinical trials

BACKGROUND

The Lansky Play-Performance Scale (LPPS) is often used to determine a child's performance status for cancer clinical trial eligibility. Differences between clinician and caregiver LPPS ratings and their associations with child-reported functioning have not been evaluated.

METHODS

Children aged 7 to 18 years who were receiving cancer treatment and their caregivers were recruited from 9 pediatric cancer centers. Caregivers and clinicians reported LPPS scores, and children completed Patient-Reported Outcomes Measurement Information System (PROMIS) pediatric functioning and symptom measures before treatment (time 1 [T1]) and after treatment (time 2 [T2]). t tests and mixed-linear models were used to assess differences in caregiver and clinician LPPS scores; polyserial correlations quantified associations between PROMIS and LPPS scores.

RESULTS

Of 482 children, 281 had matched caregiver- and clinician-reported LPPS T1/T2 scores. Caregivers rated children significantly worse on the LPPS than clinicians at both T1 (mean, 73.3 vs 87.4; P < .01) and T2 (mean, 67.9 vs 83.1; P < .01). These differences were not related to a child's age (P = .89), diagnosis (P = .17), or sex (P = .64) or to the time point (P = .45). Small to moderate associations existed between caregiver- and clinician-reported LPPS ratings and child-reported PROMIS scores for mobility (caregiver T1/T2 r = 0.51/0.45; P < .01; clinician T1/T2 r = 0.40/0.35; P < .01), fatigue (caregiver T1/T2 r = -0.46/-0.37; P < .01; clinician T1/T2 r = -0.26/-0.27; P < .01), and pain interference (caregiver T1/T2 r = -0.32/-0.30; P < .01; clinician T1/T2 r = -0.17/-0.31; P < .01). Caregivers and clinicians assigned significantly lower LPPS scores at T2 (caregiver Δ = -5.37; P < .01; clinician Δ = -4.20; P < .01), whereas child-reported PROMIS scores were clinically stable.

CONCLUSIONS

Significant differences between clinician and caregiver LPPS ratings of child performance were sustained over time; their associations with child reports were predominantly small to moderate. These data suggest that clinician-reported LPPS ratings by themselves are inadequate for determining clinical trial eligibility and should be supplemented by appropriate measures of a child's functional status reflecting the child and caregiver perspectives.

Referral Patterns and Treatment Delays in Medulloblastoma: A Large Academic Proton Center Experience

Purpose

Patient travel time can cause treatment delays when providers and families decide to seek proton therapy. We examined whether travel distance or referral pattern (domestic versus international) affects time to radiation therapy and subsequent disease outcomes in patients with medulloblastoma at a large academic proton center.

Patients and Methods

Children with medulloblastoma treated at MD Anderson (MDA) with a protocol of proton beam therapy (PBT) between January 4, 2007, and June 25, 2014, were included in the analysis. The Wilcoxon rank-sum test was used to study the association between time to start of radiation and distance. Classification- and regression-tree analyses were used to explore binary thresholds for continuous covariates (ie, distance). Failure-free survival was defined as the time interval between end of radiation and failure or death.

Results

96 patients were included in the analysis: 17 were international (18%); 19 (20%) were from Houston, Texas; 21 were from other cities inside Texas (21%); and 39 (41%) were from other US states. The median time from surgery to start of radiation was not significantly different for international patients (median = 1.45 months) compared with US patients (median = 1.15 months; P = .13). However, time from surgery to start of radiation was significantly longer for patients residing > 1716 km (> 1066 miles) from MDA (median = 1.31 months) than for patients residing ≤ 1716 km (≤ 1066 miles) from MDA (median = 1.05 months; P = .01). This 1- to 2-week delay (median = 7.8 days) did not affect failure-free survival (hazard ratio = 1.34; P = .43).

Conclusion

We found that short delays in proton access can exist for patients traveling long distances to proton centers. However, in this study, treatment delays did not affect outcomes. This highlights the appropriateness of PBT in the face of travel coordination. Investment by proton centers in a rigorous intake process is justified to offer timely access to curative PBT.