PROTON THERAPY FOR PEDIATRIC CRANIAL TUMORS - PRELIMINARY-REPORT ON TREATMENT AND DISEASE-RELATED MORBIDITIES

Purpose: Accelerated protons were used in an attempt to limit treatmen t-related morbidity in children with tumors in or near the developing brain, by reducing the integral dose to adjacent normal tissues. Metho ds and Materials: Children treated with protons at Loma Linda Universi ty Medical Center between August 1991 and December 1994 mere analyzed retrospectively. Twenty-eight children, aged 1 to 18 years, were ident ified as at risk for brain injury from treatment. Medical records, phy sical examinations, and correspondence with patients, their parents, a nd referring physicians were analyzed. The investigators tabulated pos t treatment changes in pre-treatment signs and symptoms and made judgm ents as to whether improvement, no change, or worsening related to dis ease or treatment had supervened. Magnetic resonance images were corre lated with clinical findings and radiographic impressions were tabulat ed. Results: Follow-up ranged from 7 to 49 months (median 25 months). Four instances of treatment-related morbidity were identified. Forty-o ne instances of site-specific, disease-related morbidity were identifi ed: 15 improved or resolved and 26 remained unchanged after treatment. Four patients had radiographic evidence of local failure. Three of th ese patients, including two with high-grade glioma, have died. Conclus ion: Early treatment-related morbidity associated with proton therapy is low. Tumor progression remains a problem when treating certain hist ologies such as high-grade glioma. Escalating the dose delivered to ta rget volumes may benefit children with tumors associated with poor rat es of local control. Long-term follow-up, including neurocognitive tes ting, is in progress to assess integral-dose effects on cognitive, beh avioral and developmental outcomes in children with cranial tumors. (C ) 1997 Elsevier Science Inc.