Brain stem tumors in children and adolescents: single institutional experience

Pediatric brain stem tumors (BsT) are a heterogeneous group of diseases. Our aim was to analyze our experience to find out prognostic factors. A retrospective study with BsT patients was performed. Imaging characteristics, extension of surgery, pathology, and adjuvant therapy were analyzed and correlated with overall survival (OS) and progression-free survival (PFS) as outcome measures. Since 1980 to 2010, we analyzed 65 BsT patients, 41 of them girls (63 %), median age of 8 years (range 13.9 months to 17.6 years). Twenty-two patients (33.8 %) had diffuse intrinsic pontine gliomas (DIPG) and 43 (66.2 %) presented with focal BsT. Histology was available in 42 patients; the most frequent is low-grade glioma in 24/42 patients (57 %). DIPG's histology (obtained usually at necropsy) confirmed five high-grade gliomas. After median follow-up of 49.3 months (0.5-175 months), 20/22 DIPG patients have died (90.9 %), while 27/43 with focal tumors were alive (62.8 %). Variables related to outcome were histology (better for low-grade glioma (LGG) OS p < 0.001), surgery (better if operated OS p < 0.001), and adjuvant therapy (worse if given, PFS p = 0.001, OS p = 0.024). The outcome for DIPG was dismal, median OS/EFS of 14.2/9.4 months, significantly worse than focal BsT (p = 0.000), while OS/EFS was 122.8/87.2 months for focal intrinsic, 88.2/47.1 months for exophytic, and 124.4/54 months for cervico-medullary tumors: no differences were found among them, except the histology (OS p < 0.001 for low-grade vs high-grade tumors). BsT in children comprised two different groups: diffuse (DIPG) and focal gliomas. The DIPGs continue having a dismal prognosis, needing new approaches, while focal tumors including LGG have better prognosis.