2375 - Proton Therapy in Pediatric Craniopharyngioma: Comparison between Adjuvant and Salvage Radiotherapy Efficacy and Toxicity
Presenter(s)
O. Haisraely1, D. R. Grosshans2, S. L. McGovern1, M. F. F. McAleer3, W. Zaky4, S. David4, M. Chintagumpala5, G. Aldave Orzaiz6, F. Okcu7, and A. C. Paulino1; 1Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 2Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 3Department of Radiation Oncology, Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, 4MD Anderson Cancer Center, Houston, TX, 5Texas Children's Cancer Center, Baylor College of Medicine, Houston, TX, 6Texas Children Hospital, houston, TX, 7TCH, HOUSTON, TX
Purpose/Objective(s): Craniopharyngiomas are rare tumors associated with significant morbidity, including visual, endocrine, vascular, and neurological dysfunction. Proton therapy (PT) is used after biopsy or subtotal resection (adjuvant) or after resection and tumor progression (salvage). This study compares progression-free survival (PFS), overall survival (OS), and treatment-related toxicity after adjuvant vs. salvage PT.
Materials/Methods: We reviewed 43 pediatric craniopharyngioma patients from two prospective late-effects studies at a single institution. Thirty-three had adjuvant and 10 had salvage PT. Median prescribed dose was 50.4 Gy (range: 50.4–55.8 Gy), with adaptive re-planning in 20.1%. Statistical analyses included T-tests for parametric variables and chi-square tests for categorical variables. Progression was defined as solid growth or persistent cystic growth beyond three years post-treatment.
Results: Median age at diagnosis was 9.1 years (range: 2.8–16.4), and the median time from diagnosis to radiation was 6.5 months (range: 2–163). At a median follow-up of 4.2 years, 4-year PFS was 83.7%, nodular PFS was 93%, cystic PFS was 90.9%, and OS was 93%. There was no significant difference in PFS or OS between adjuvant and salvage RT. Salvage RT was associated with higher toxicity, including visual impairment (40% vs. 8%, p=0.02) and panhypopituitarism (55.5% vs. 18.5%, p=0.039). One secondary malignancy was reported.
Conclusion: Proton therapy provides excellent tumor control with minimal acute toxicity in pediatric craniopharyngioma. However, salvage RT resulted in increased visual and endocrine toxicity. Long-term multidisciplinary follow-up is essential to mitigate late effects and optimize outcomes.
Abstract 2375 - Table 1| Parameter | Adjuvant (n=33) | Salvage (n=10) | p-value |
| Age (median, range) | 8.8 (4.5-16.4) | 6.5 (2.8-11.4) | 0.056 |
| Female (%) | 51.5% (17/33) | 50% (5/10) | 0.87 |
| Time from diagnosis to RT (months) | 4 (2-9) | 24 (5-163) | <0.001 |
| Visual toxicity | 8% (2/25) | 40% (4/10) | 0.027 |
| Panhypopituitarism (>2 deficits) | 18.5% (5/27) | 55.5% (5/9) | 0.039 |
| Diabetes insipidus | 82.1% (23/28) | 77.7% (7/9) | 0.69 |
| Hypothalamic obesity | 59.3% | 57% | 0.33 |
| Vasculopathy | 4% (1/25) | 25% (2/8) | 0.06 |
| Follow-up time (years) | 3.85 | 4.4 | 0.44 |
| 4-year PFS | 84.8% | 80% | 0.102 |
| 4-year OS | 93.9% | 90% | 0.23 |