CNS & pituitary tumors
Pineal tumors
Pineoblastoma
Author: Nat Pernick, M.D.
Last author update: 1 January 2006
Last staff update: 20 May 2021
Copyright: 2002-2023, PathologyOutlines.com, Inc.
PubMed Search: Pineoblastoma [title]
Table of Contents
Definition / general | Case reports | Treatment | Gross description | Microscopic (histologic) description | Cytology images | Positive stains | Negative stains | Electron microscopy description | Electron microscopy images | Differential diagnosisCite this page: Pernick N. Pineoblastoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/cnstumorpineoblastoma.html. Accessed March 22nd, 2023.
Definition / general
- Grade IV of IV
- Second most common pineal gland tumor after germ cell tumor
- Usually age 20 years or less
- Frequent CNS metastases or spinal seeding, which is the main cause of death
- 5 year survival is 58%
- Poor prognostic factors:
- 7+ mitotic figures/10 HPF
- Presence of necrosis
- No neurofilament staining
Case reports
- 15 year old girl with intracranial midline mass (Arch Pathol Lab Med 2004;128:707)
- 18 and 26 year old men with vertebral metastases from pineoblastoma (Arch Pathol Lab Med 2001;125:939)
- Osseous metastasis of pineoblastoma (J Neurooncol 2005;74:53)
Treatment
- Surgery, variable radiation therapy
- Prognosis is usually poor
Gross description
- Located in pineal gland
- May appear well demarcated from surrounding brain tissue but usually infiltrates into surrounding structures
Microscopic (histologic) description
- Sheets of densely packed cells with high grade (anaplastic / undifferentiated) features including high N/C ratio with minimal cytoplasm and large hyperchromatic nuclei
- Also necrosis, frequent mitotic figures
- Focal nuclear molding
- Homer Wright or Flexner-Wintersteiner rosettes
- May have lower grade features of pineocytoma and pineal parenchymal tumor of intermediate differentiation
- Often infiltrates into surrounding structures
Cytology images
Images hosted on other servers:
Small blue cell neuroepithelial malignant tumor
Positive stains
- NSE, synaptophysin, retinal S antigen
Electron microscopy description
- Occasional cytoplasmic dense core granules
- Short immature cell processes
- Occasional junctional complexes
- No definite synapses
Electron microscopy images
Images hosted on other servers:
Presence of abundant filopodia and rare intercellular junctions but no definitive synapses
Differential diagnosis
- Glial neoplasms: GFAP+
- Medulloblastoma
- Pineocytoma: better differentiated cells with more cytoplasm, smaller cells, no / rare mitotic figures
