Positron emission tomography for the early postsurgical evaluation of pediatric brain tumors

Object The object was to study the value of postoperative positron emission tomography (PET) to assess the extension of brain tumor resection.Methods Twenty children operated on for total resection of a glial tumor (18 low-grade, 2 anaplastic) presented a signal on postoperative magnetic resonance (MR) images raising the question of a possible tumor residue. PET was performed early (¹⁸F-Fluoro-deoxyglucose in 1, ¹¹C-methionine in 16, both in 3) to further characterize the nature of the abnormal MR signal in order to consider second-look surgery. An increased tracer uptake found in 14 children led to reoperation on 11 of them, confirming the tumor histologically. No ¹¹C-methionine uptake led to a conservative attitude in 6 children in whom MR imaging follow-up showed no tumor progression.Conclusions The early postoperative PET, especially with ¹¹C-methionine, appears to be a valid basis for complementary therapeutic decisions, especially second-look surgery, in glial tumors for which a radical resection is a key factor for prognosis.