CLINICAL STUDY – PATIENT STUDY Incidental brain lesions in children: to treat or not to treat? Amy-Lee Bredlau • Louis S. Constine • Howard J. Silberstein • Michael T. Milano • David N. Korones Received: 19 April 2011 / Accepted: 9 August 2011 / Published online: 19 August 2011 Ó Springer Science+Business Media, LLC. 2011 Abstract Central nervous system (CNS) lesions that are discovered incidentally when imaging children for prob- lems that were unrelated to the detected lesion pose a dilemma to physicians. Because there are few data on the outcome of such cases, we retrospectively reviewed the clinical course of a group of children followed at our institution with brain lesions found incidentally on neuro- imaging. A database of all children with brain lesions followed at the University of Rochester medical center from 2000 to 2010 was reviewed. Data were obtained regarding presentation, magnetic resonance imaging (MRI) features, treatment, progression-free survival, and overall survival of children with brain lesions found incidentally. Of the 244 children with brain lesions seen over this time period, 21 (8.6%) were found to have incidentally dis- covered brain lesions. Of these 21 children, 12 (57%) underwent surgical resection of their brain lesions. Ten patients (48%) had symptoms considered to be unassoci- ated with the detected lesion. Lesions were found in the cerebellum (n = 7, 33%), midline (n = 5, 24%), and cerebrum (n = 9, 43%). All lesions were B5 cm in diam- eter. Eight patients (38%) had surgery at presentation, one because of imaging features suspicious for a posterior fossae ependymoma, and the seven others because of location in the posterior fossae or brain stem. Of the remaining 13 patients, five had progression of disease on serial MRI scans: four underwent surgery and the fifth was monitored and remained stable after the initial progression stabilized. Nine of the ten patients (90%) with posterior fossae lesions underwent surgery, while only three of 11 with supratentorial lesions underwent surgery (27%) (P = 0.006). The progression free survival was 94% at 12 months (95% CI 65–99%) and 71% at 24 months (95% CI 39–88%). At a median follow-up of 32 months, the overall survival was 100%. Incidentally detected CNS lesions are usually small. The outcome for children with such lesions is excellent. Close monitoring of these patients with serial MRIs may be a safe alternative to immediate biopsy and/or resection for select patients. Keywords Incidental Á Brain tumor Á Brain lesion Á Children Á Incidentaloma Introduction It is not uncommon for pediatric oncologists to see children with incidentally found brain lesions on computerized tomography (CT) or magnetic resonance imaging (MRI) scans. These imaging modalities are frequently used by pediatricians, pediatric neurologists, and emergency room physicians to evaluate children who have suffered head trauma, have headaches or other neurologic symptoms. Occasionally, a lesion is discovered that is not related to the indication for obtaining the study. A number of investigations have been conducted on healthy patients, attempting to estimate how common incidentally found brain lesions are in healthy children and adults. Most of these investigations have focused on all abnormalities found on imaging, including sinusitis, Chiari malforma- tions, and arterio–venous malformations [1–4]. In 2002, Kim and co-workers [2] retrospectively evaluated MRIs from 225 neurologically healthy children and found no neoplastic lesions. Gupta and Belay retrospectively A.-L. Bredlau (&) Á L. S. Constine Á H. J. Silberstein Á M. T. Milano Á D. N. Korones University of Rochester, 601 Elmwood Avenue, Box 777, Rochester, NY 14642, USA e-mail: amy-lee_bredlau@urmc.rochester.edu 123 J Neurooncol (2012) 106:589–594 DOI 10.1007/s11060-011-0695-1