Role of MRI in the management of children with diffuse pontine tumors: a study of 15 patients and review of the literature

Pontine tumors carry the worst prognosis of all brain tumors. In most cases, the diagnosis is based solely on MR imaging, without biopsy. To describe the MR findings of pontine tumors at diagnosis and during follow-up and correlate those with prognosis and to assess the value of MR imaging in patient management compared to clinical evaluation. Ninety-one MR scans of 15 children with diffuse pontine tumors were reviewed at diagnosis and during follow-up. The parameters analyzed were as follows: tumor extent, area, and volume; encasement of the basilar artery; presence of exophytic component; necrosis; cysts; hydrocephalus; and intensity and enhancement. Findings were correlated to length of progression-free and overall survival. Trends of amelioration or worsening on imaging were compared with the clinical findings. Median length of progression-free survival was 10 months, and median survival was 20 months. Only hydrocephalus at presentation was associated with shorter progression-free survival (P=0.02). On the last examination of each patient, the craniocaudal diameter was significantly greater than at diagnosis (P=0.03). The concordance between the imaging and the clinical findings was good. MR is the mainstay for the diagnosis and management of pontine tumors. Cranial growth seems to be an ominous sign. However, the prognostic value of MR is limited. MR findings correlate well with the clinical examination.