Natural history of a medulloblastoma: 30 months of wait and see in a child with a cerebellar incidentaloma

Incidental Brain Tumors in the Pediatric Population: A Systematic Review and Reappraisal of Literature

OBJECTIVES

Management of incidental asymptomatic brain tumors in children is controversial due to lack of clear evidence-based guidelines. We present this systematic review in an attempt to highlight an optimal treatment paradigm.

METHODS

This systematic review was conducted in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Databases were searched up to August 2019 using the keywords "incidental," "brain tumor," and "pediatric." Our main focus was on brain lesions suspected for neoplasm, diagnosed incidentally on neuroimaging in an otherwise asymptomatic patient <18 years old. Cystic, vascular, and inflammatory brain lesions were excluded.

RESULTS

Fourteen studies comprising 308 patients were included. All cases were diagnosed using magnetic resonance imaging. The most common indications for imaging were headache (93; 30%) and trauma (72; 23%). Lesion distribution was supratentorial (179; 58%), infratentorial (121; 40%), and intraventricular (8; 3%). Of 308 cases, 243 (79%) were managed with neuroradiological surveillance and 57 (19%) by upfront surgical excision. Of those managed conservatively, 177 (73%) remained stable within a mean follow-up of 30 months, 54 (22%) progressed, and 12 (5%) spontaneously regressed. Meanwhile, upfront excision achieved complete remission in all 57 cases over a mean follow-up of 68.3 months.

CONCLUSION

A small body of evidence has emerged, highlighting the marked heterogeneity and contradictory results between the available studies, limiting our ability to draw solid conclusions. At this point, the decision between surgery and "watchful waiting" should be tailored on an individual patient basis depending on suspicion of malignancy, clinical or radiologic progression, and parental preference.

Natural History of Medulloblastoma in a Child with Neurofibromatosis Type I

Medulloblastoma is one of the common posterior fossa tumors in children. The natural history of this tumor in presymptomatic period is not well known. Widespread use of brain imaging has increased the detection of incidental brain tumors in totally asymptomatic persons. Here, we report a case of a 4-year-old boy with prenatal diagnosis of congenital brain abnormalities and neurofibromatosis type I. He underwent regular brain imaging to follow interhemispheric arachnoid cyst and ventriculomegaly that a posterior fossa tumor was discovered. The tumor size increased during time and became symptomatic after 28 months which was resected.