Clinical outcomes and quality of life in children and adolescents with primary brain tumors treated with pencil beam scanning proton therapy
Sébastien Tran, Pei Lim, Beat Bojaxhiu, C. Teske, Katja Baust, Stefan Zepter, Ulrike Kliebsch, Beate Timmermann, Gabriele Calaminus, Damien C. Weber
Abstract
BACKGROUND: Long-term treatment-related toxicity may substantially impact well-being, quality of life (QoL), and health of children/adolescents with brain tumors (CBTs). Strategies to reduce toxicity include pencil beam scanning (PBS) proton therapy (PT). This study aims to report clinical outcomes and QoL in PBS-treated CBTs. PROCEDURE: We retrospectively reviewed 221 PBS-treated CBTs aged <18 years. Overall-free (OS), disease-free (DFS), and late-toxicity-free survivals (TFS), local control (LC) and distant (DC) brain/spinal control were calculated using Kaplan-Meier estimates. Prospective QoL reports from 206 patients (proxies only ≤4 years old [yo], proxies and patients ≥5 yo) were descriptively analyzed. Median follow-up was 51 months (range, 4-222). RESULTS: Median age at diagnosis was 3.1 years (range, 0.3-17.7). The main histologies were ependymoma (n = 88; 39.8%), glioma (n = 37; 16.7%), craniopharyngioma (n = 22; 10.0%), atypical teratoid/rhabdoid tumor (ATRT) (n = 21; 9.5%) and medulloblastoma (n = 15; 6.8%). One hundred sixty (72.4%) patients received chemotherapy. Median PT dose was 54 Gy(relative biological effectiveness) (range, 18.0-64.8). The 5-year OS, DFS, LC, and DC (95% CI) were 79.9% (74-85.8), 65.2% (59.8-70.6), 72.1% (65.4-78.8), and 81.8% (76.3-87.3), respectively. Late PT-related ≥G3 toxicity occurred in 19 (8.6%) patients. The 5-year ≥G3 TFS was 91.0% (86.3-95.7). Three (1.4%) secondary malignancies were observed. Patients aged ≤3 years at PT (P = .044) or receiving chemotherapy (P = .043) experienced more ≥G3 toxicity. ATRT histology independently predicted distant brain failure (P = .046) and death (P = .01). Patients aged ≥5 years self-rated QoL higher than their parents (proxy assessment). Both reported lower social functioning and cognition after PT than at baseline, but near-normal long-term global well-being. QoL was well below normal before and after PT in children ≤4 years. CONCLUSIONS: The outcome of CBTs was excellent after PBS. Few patients had late ≥G3 toxicity. Patients aged <5 years showed worse QoL and toxicity outcomes.