Table 3.
Summary of non-high-grade glioma pathologies reported in surgical case series of pediatric brainstem biopsy.
| Study | Details of included patients and reasons for conducting biopsy (if provided) | Histological subtypes identified (emphasis on non-glioma findings) |
|---|---|---|
| Roujeau 2007 (42) | 24 children all with ‘diffuse pontine lesions’ | 22 children had WHO III/IV gliomas. 1 child had pilocytic astrocytoma, and 1 had WHO II astrocytoma. In these low-grade lesions, up-front radiation was not used and these children were not enrolled in a trial investigating a chemotherapeutic agent for malignant tumors. |
| Pirotte 2007 (43) | 20 children with ‘intrinsic brainstem tumors’. Biopsies were being conducted because of atypical features (either lateralization within the brainstem or strong contrast enhancement) | 2 patients had pilocytic astrocytomas (1 lesion was subependymal in the pons, the other was lateralized within the pons), 2 lateralized pontine lesions were called ‘PNET’s |
| Schumacher 2007 (5) | 142 cases of pediatric ‘brainstem disease’, analysis conducted to find correlation between radiographic diagnosis from MRI (3 radiologists) and final histopathological diagnosis | The radiologists correctly identified non-tumor disease 50-75% of the time. They correctly identified gliomas 85-91% of the time. |
| Patel 2009 (44) | 24 stereotactic brainstem biopsies | 8 patients had pilocytic astrocytomas, 2 had tuberculous lesions, 1 had an epidermoid cyst, and 1 had infarction. No details of radiographic features of these lesions were provided. |
| Haegelen 2010 (45) | 6 biopsies in children with brainstem lesions | 1 patient had gliosis (imaging characteristics not provided) |
| Dellaretti 2011 (46) | 44 children with intrinsic brainstem lesions | Of the patients with diffuse lesions (29), non-glioma pathologies were found in 2 patients: 1 ependymoma and 1 ganglioglioma |
| Ogiwara 2013 (47) | 7 biopsies for ‘intrinsic brainstem lesions’ in children, reason for biopsy was “atypical” feature (extension beyond the boundary of the pons, or well-margined localized enhancing portion). | 1 patient had PNET, 1 patient had pilocytic astrocytoma |
| Manoj 2014 (48) | 41 children underwent stereotactic biopsy for brainstem lesions | 3 cases of pilocytic astrocytoma, 4 tuberculomas, 1 “other inflammatory”. Authors note “all the biopsies in diffuse non-enhancing lesions were gliomas” |
| Quick-Weller 2017 (49) | 5 children with intrinsic brainstem lesions suspected to be high grade gliomas | 1 child had astrogliosis, T-cell infiltration and mineralization without tumor cells, this child was observed clinically with no progression. A second child was found to have pilocytic astrocytoma. A ‘wait and see’ strategy was adopted and the lesion showed remission on radiographic follow-up. |
| Dawes 2018 (50) | 11 robotic brainstem biopsies in children | 1 patient had an inflammatory lesion (imaging characteristics not provided) |
| Gupta 2020 (51) | 22 robotic brainstem biopsies in children | 2 had pilocytic astrocytomas (imaging characteristics not provided) |
| Peruzzi 2024 (52) | Case report of a 19 year old female with MRI consistent with DIPG | Biopsy showed lesional cells were negative for H3K27M alterations, sequencing revealed frameshift mutation in NF1 thought to be likely driver mutation |