Incidental brain tumors in children: an international neurosurgical, oncological survey

Surgical Treatment of Pediatric Incidentally Found Brain Tumors: A Single-Center Experience

There remains much debate about the correct management of incidentally found brain tumors in the pediatric population. This study aimed to evaluate the efficacy and safety of surgical treatment of incidentally found pediatric brain tumors. A retrospective analysis of pediatric patients who underwent surgical resection of incidentally found brain tumors between January 2010 and April 2016 was performed. A total of seven patients were included. The median age at the time of diagnosis was 9.7 years. The reasons for performing neuroimaging were as follows: impeded speech development (n = 2), shunt control (n = 1), paranasal sinuses control (n = 1), behavior changes (n = 1), head trauma (n = 1), and preterm birth (n = 1). Five patients underwent gross total tumor resection (71.4%), while subtotal resection was performed in two patients (28.6%). There was no surgery-related morbidity. Patients were followed up for a mean of 79 months. One patient with atypical neurocytoma experienced tumor recurrence 45 months following primary resection. All patients remained neurologically intact. The majority of pediatric incidentally found brain tumors were histologically benign. Surgery remains a safe therapeutic approach associated with favorable long-term outcomes. Considering the expected long lifetime of pediatric patients, as well as the psychological burden associated with having a brain tumor as a child, surgical resection can be considered an initial approach.

Approaches to Incidental Intradural Tumors of the Spine in the Pediatric Population

BACKGROUND

Incidental intradural tumors of the spine in the pediatric population are rare lesions whose management remains unclear. Surgeons must balance the risks of iatrogenic deficits and complications after surgical resection against the risks from progressive growth of the tumor. Moreover, the natural history of an incidental finding can be difficult to predict. Here, we review the literature on incidental intradural tumors of the spine and present considerations for their management.

SUMMARY

Growth of the tumor or changes in radiographic features are usually indications for resection. Asymptomatic lesions can be found in patients with genetic syndromes that predispose to tumor formation, such as neurofibromatosis type 1 and 2, schwannomatosis, and Von-Hippel-Lindau syndrome, and careful workup of a genetic cause is warranted in any patient presenting with multiple tumors and/or cutaneous features. Close follow-up is generally favored given the heavy tumor burden; however, some recommend pre-emptive resection to prevent permanent neurological deficits. Incidental intradural tumors can also occur in association with hydrocephalus, significant syringomyelia, and cord compression, and surgical treatment is usually warranted. Tumors may also be discovered as part of the workup for scoliosis, where they are not truly incidental to the scoliosis but rather are contributing to curve deformation.

KEY MESSAGES

Thorough workup of patients for associated genetic syndromes or comorbidities should be undertaken in pediatric patients with incidental intradural tumors. Further research is needed into the natural history of these incidental lesions. Incidental tumors can often be managed conservatively with close follow-up, with surgical intervention warranted for expanding tumors or new-onset symptoms.

Supratentorial Pediatric Midline Tumors and Tumor-like Lesions: Clinical Spectrum, Natural History and Treatment Options

Childhood Central Nervous System tumors account for 25% of all pediatric tumors. Large availability and broadening of indications to imaging has made incidental findings more common. Among these, midline lesions have different clinical relevance depending on their intrinsic pattern of behaviour and on their specific location. In this narrative review we describe the natural history and treatment options of midline lesions in children.

Pediatric thalamic incidentalomas: an international retrospective multicenter study

OBJECTIVE

Widespread use of modern neuroimaging has led to a surge in diagnosing pediatric brain incidentalomas. Thalamic lesions have unique characteristics such as deep location, surgical complexity, and proximity to eloquent neuronal structures. Currently, the natural course of incidental thalamic lesions is unknown. Therefore, the authors present their experience in treating such lesions.

METHODS

A retrospective, international multicenter study was carried out in 8 tertiary pediatric centers from 5 countries. Patients were included if they had an incidental thalamic lesion suspected of being a tumor and were diagnosed before the age of 20 years. Treatment strategy, imaging characteristics, pathology, and the outcome of operated and unoperated cases were analyzed.

RESULTS

Overall, 58 children (23 females and 35 males) with a mean age of 10.8 ± 4.0 years were included. The two most common indications for imaging were nonspecific reasons (n = 19; e.g., research and developmental delay) and headache unrelated to small thalamic lesions (n = 14). Eleven patients (19%) underwent early surgery and 47 were followed, of whom 10 underwent surgery due to radiological changes at a mean of 11.4 ± 9.5 months after diagnosis. Of the 21 patients who underwent surgery, 9 patients underwent resection and 12 underwent biopsy. The two most frequent pathologies were pilocytic astrocytoma and WHO grade II astrocytoma (n = 6 and n = 5, respectively). Three lesions were high-grade gliomas.

CONCLUSIONS

The results of this study indicate that pediatric incidental thalamic lesions include both low- and high-grade tumors. Close and long-term radiological follow-up is warranted in patients who do not undergo immediate surgery, as tumor progression may occur.

Incidental Findings on Brain Magnetic Resonance Imaging (MRI) in Pediatric Endocrine Patients

OBJECTIVE

To explore incidental findings on brain magnetic resonance imaging (MRI) studies of pediatric patients referred due to endocrine disorders.

METHODS

A retrospective, observational study conducted in a tertiary referral center. The neuroimaging database of 17,445 brain MRI studies of 11,011 pediatric patients were searched for cases with endocrine referrals and without medical history of malignancy, genetic syndromes, and/or neurologic comorbidities. This database was linked to the pediatric neurosurgical database. Clinical data were retrieved from medical files.

RESULTS

In total, 524 patients (50.2% males, mean age 8.5±3.5 years) were referred to brain MRI due to growth disturbances (n = 313), pubertal disorders (n = 183), prolactin hypersecretion (n = 18), central diabetes insipidus (n = 8), and obesity (n = 1). Incidental findings were found in 128 (24.4%) cases. Chiari type 1 malformation was more prevalent in patients with growth disturbances (P<.001). Small pituitary cysts were observed in 20 (3.8%) patients, and pineal cysts in 25 (4.8%) patients, mostly girls (68%, P<.001). White matter lesions were diagnosed in 30 (5.7%) patients, none with clinical evidence of neurologic disease. Brain asymmetry without clinical significance and developmental venous anomalies were observed in 14 (2.7%) and 8 (1.5%) patients, respectively. Twelve patients were diagnosed with intracranial tumors, and 5 required surgical intervention for a histopathologic diagnosis of juvenile pilocytic astrocytoma (n = 3), choroid plexus papilloma (n = 1), or inconclusive (n = 1). The rest were managed conservatively.

CONCLUSION

Incidental findings on brain MRIs of pediatric patients referred by endocrinologists are common and raise dilemmas. The spectrum ranges from structural disruptions to tumors. Decision-making is individualized and patient-centered.

Management of incidental brain tumors in children: a systematic review

BACKGROUND

Due to technical advancements and availability of neuroimaging, detection of incidental pediatric brain tumors (IPBT) is growing rapidly. The management of these asymptomatic lesions remains unclear; radiological, pathological, and clinical risk factors for further growth and malignant transformation (MT) are not well defined.

METHODS

We systematically reviewed the literature on the dilemmas and management of IPBT suggestive of a low-grade brain tumor (LGBT). Keyword searches of the PubMed and Medline (NCBI) databases identified studies on IPBT describing the prevalence, neuroimaging, management, or risk of MT through July 2019. References of the identified articles were also reviewed.

RESULTS

A total of 2021 records were screened. Fifty-nine full-text articles were reviewed, and 34 published studies were included. IPBT are diagnosed in 0.2-5.7% of children undergoing brain imaging for various reasons. The accepted approach for management of lesions showing radiological characteristics suggestive of LGBT is radiological follow-up. The rate at which additional intervention is required during follow-up for these apparently low-grade lesions is 9.5%. Nevertheless, the dilemma of early surgical resection or biopsy vs. clinical and radiological follow-up of IPBT is still unresolved. The risk in these cases is missing a transformation to a higher grade tumor. However, MT of pediatric LGBT is very rare, occurring in less than 3% of the cases of proven low-grade gliomas in children. The risk of future MT in pediatric low-grade gliomas seems to be greater in the presence of specific molecular markers such as BRAF V-600E, CDKN2A, and H3F3A K27M.

CONCLUSIONS

The natural history, management, and prognosis of IPBT remain ambiguous. It seems that lesions suggestive of LGBT can initially be followed, since many of these lesions remain stable over time and MT is rare. However, controversy among centers concerning the ideal approach still exists. Further observational and prospective cohort studies, focusing on potential clinical and radiological characteristics or risk factors suggestive of high-grade tumors, tumor progress, or MT of IPBT, are needed.

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.

Pediatric posterior fossa incidentalomas

PURPOSE

Pediatric brain incidentalomas are increasingly being diagnosed. As the posterior fossa (PF) is the location of most brain tumors in children, lesions of this region are of special interest. Currently, the natural history of incidental lesions in the PF is unknown. We present our experience treating such lesions.

METHODS

A retrospective study was carried out in two large tertiary pediatric centers. Patients were included if they had an incidental PF lesion suspected of being a tumor, and diagnosed before the age of 20 years. We analyzed treatment strategy, pathology, and outcome of operated and non-operated cases.

RESULTS

Seventy children (31 females) with a mean age of 8.4 ± 6.1 years were included. The three most common indications for imaging were headaches (16, assumed to be unrelated to the lesions), workup of unrelated conditions (14), and unspecified reasons (14). Twenty-seven patients (39%) were operated immediately, and 43 followed, of which 12 were eventually operated due to radiological changes, 28.9 ± 16.2 months after diagnosis. The most commonly found pathology was pilocytic astrocytomas (21 of 39 operated cases). Almost 10% were found to be malignant tumors including medulloblastomas (5) and ATRT (1).

CONCLUSION

Incidental PF lesions in children include both benign and malignant tumors. While certain lesions may be followed, others may require surgical treatment. Specific treatment decisions are based on initial radiological appearance, change in radiological characteristics over time, location, and evolving symptoms. The surgical risks must be balanced vis-à-vis the risk of missing a high-grade tumor and the very rare risk of malignant transformation.