Publications by authors named "John Han-Chih Chang"

Purpose: Increasing concern that brainstem toxicity incidence after proton radiation therapy might be higher than with photons led to a 2014 University of Florida (UF) landmark paper identifying its risk factors and proposing more conservative dose constraints. We evaluated how practice patterns changed among the Pediatric Proton/Photon Consortium Registry (PPCR).

Material And Methods: This prospective multicenter cohort study gathered data from patients under the age of 22 years enrolled on the PPCR, treated between 2002 and 2019 for primary posterior fossa brain tumors.

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Purpose: Craniospinal irradiation (CSI) is commonly used for pediatric brain tumors with a propensity for spread in craniospinal fluid, principally medulloblastoma. Evolving technology has led to the use of highly conformal radiation therapy (RT) techniques for CSI, including proton therapy. Target delineation and plan coverage are critical for CSI, but there is ongoing controversy and variability in these realms, with little available data on practice patterns.

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The survival of patients with acute lymphoblastic leukemia (ALL) has improved significantly with the use of intensive multimodality treatment regimens including chemotherapy, high-dose chemotherapy and stem cell rescue, and radiation therapy when indicated. This report summarizes the treatment strategies, especially radiation therapy in the Children's Oncology Group for children with ALL. Currently, radiation therapy is only indicated for children with high-risk CNS involvement at diagnosis or relapse, testicular relapse and as part of the conditioning regimen for hematopoietic stem cell transplantation.

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Objective: The Pediatric Proton/Photon Consortium Registry (PPCR) is a comprehensive data registry composed of pediatric patients treated with radiation. It was established to expedite outcomes-based research. The attributes which allow the PPCR to be a successful collaboration are reviewed.

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Background: Survivors of pediatric brain tumors are at risk for impaired development in multiple neuropsychological domains. The purpose of this study was to compare neuropsychological outcomes of pediatric brain tumor patients who underwent X-ray radiotherapy (XRT) versus proton radiotherapy (PRT).

Methods: Pediatric patients who underwent either XRT or PRT and received posttreatment age-appropriate neuropsychological evaluation-including measures of intelligence (IQ), attention, memory, visuographic skills, academic skills, and parent-reported adaptive functioning-were identified.

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Background: Children with brain tumors can experience symptom burden throughout their disease continuum. The aim of the study was to evaluate symptom burden reported by children with brain tumors and factors that potentially were associated with their symptoms.

Methods: Data from 199 children with brain tumors aged 7-22 (mean age = 14 years; 52% males; 76% white) were analyzed.

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Purpose: To facilitate the initiation of observational studies on late effects of proton therapy in pediatric patients, we report on current patterns of proton therapy use worldwide in patients aged less than 22 years.

Materials & Methods: Fifty-four proton centers treating pediatric patients in 2016 in 11 countries were invited to respond to a survey about the number of patients treated during that year by age group, intent of treatment, delivery technique and tumor types.

Results: Among the 40 participating centers (participation rate: 74%), a total of 1,860 patients were treated in 2016 (North America: 1205, Europe: 432, Asia: 223).

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Purpose: Randomized evidence for extreme hypofractionation in prostate cancer is lacking. We aimed to identify differences in toxicity and quality-of-life outcomes between standard fractionation and extreme hypofractionated radiation in a phase 3 randomized trial.

Methods And Materials: We analyzed the results of the first 75 patients in our phase 3 trial, comparing 38 Gy relative biologic effectiveness (RBE) in 5 fractions (n = 46) versus 79.

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Context: Monitoring of health-related quality of life and symptoms of patients with brain tumors is needed yet not always feasible. This is partially due to lack of brief-yet-precise assessments with minimal administration burden that are easily incorporated into clinics. Dynamic computerized adaptive testing (CAT) or static fixed-length short forms, derived from psychometrically sound item banks, are designed to fill this void.

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Purpose: This study evaluates acute toxicity outcomes in breast cancer patients treated with adjuvant proton beam therapy (PBT).

Methods: From 2011 to 2016, 91 patients (93 cancers) were treated with adjuvant PBT targeting the intact breast/chest wall and comprehensive regional nodes including the axilla, supraclavicular fossa, and internal mammary lymph nodes. Toxicity was recorded weekly during treatment, one month following treatment, and then every 6months according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.

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Purpose: Reirradiation therapy (re-RT) is the only potentially curative treatment option for patients with locally recurrent head and neck cancer (HNC). Given the significant morbidity with head and neck re-RT, interest in proton beam radiation therapy (PBRT) has increased. We report the first multi-institutional clinical experience using curative-intent PBRT for re-RT in recurrent HNC.

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