Optic pathway gliomas in adolescence--time to challenge treatment choices?

Abstract

Optimal management of optic pathway/hypothalamic glioma (OPHG) remains an ongoing challenge. Little is known about the natural history, management strategies, and outcomes in adolescents. Carboplatin-based chemotherapy is a useful modality in younger children, delaying radiation to their immature brains. National trials have focused on younger children and excluded adolescents from studies evaluating the role of chemotherapy. This retrospective study describes clinical characteristics, treatment regimens, and outcomes in adolescents (aged ≥ 10 years) with OPHG (diagnosis during 1990-2006). Progression-free survival was compared with that in a cohort of younger children (aged <10 years). Thirty-three adolescents (19 females, 6 with neurofibromatosis type 1) with OPHG were identified within 2 Canadian pediatric oncology institutions. The majority presented with visual symptoms (82%). More than 55% (18 of 33) involved the posterior tract and/or hypothalamus (modified Dodge classification 3/4). Seventeen were initially observed; 8 remained progression free. Of the 25 of 33 adolescents who required active treatment, 9 (36%) needed second-line therapy. The progression-free survival for any first active treatment at age <10 years (52 of 102) or ≥ 10 years (25 of 33) was similar (46.9 vs 46.8 months; P = .60). In those who received chemotherapy as first-line treatment or after prior nonchemotherapy treatment failure, the progression-free survival trend was superior (62.9 vs 38.9 months) in those aged ≥ 10 years although not statistically significant (P = .16). Chemotherapy is a valuable treatment modality for the achievement of disease control even in adolescents; their progression-free survival compares favorably with that in younger children. We propose that chemotherapy be considered as a first-line modality in adolescents, avoiding potential radiation-associated morbidities.