====== Pineal germinoma magnetic resonance imaging ======

see also [[Intracranial germ cell tumor magnetic resonance imaging]].
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Lesions are typically isodense to hyperintense to gray matter on T1- and T2-weighted MRI, with cystic and necrotic changes seen in larger masses
((Dumrongpisutikul N, Intrapiromkul J, Yousem DM. Distinguishing between germinomas and pineal cell tumors on MR imaging. AJNR Am J Neuroradiol. 2012;33(3):550–555.))
((Smith AB, Rushing EJ, Smirniotopoulos JG. From the archives of the AFIP: lesions of the pineal region: radiologic-pathologic correlation. Radiographics. 2010;30(7):2001–2020)).

Avid enhancement is seen following intravenous contrast administration. MRI of the entire neuroaxis and lumbar puncture is recommended to assess for CSF seeding and drop metastases.

In the [[pineal region]] they appear to "engulf" normal [[pineal gland]] tissue and can have associated central calcification, in contrast to [[pineocytoma]]s, and [[pineoblastoma]]s which are described as "exploding" the foci of calcification. Cystic components are common, found in upto 45% of cases.

It generally presents well-defined MRI features which usually evoke a high grade of diagnostic suspicion. Nevertheless, **bioptic confirmation**  is usually considered mandatory. However, despite modern improvements, the pineal region remains one of the more dangerous sites to perform a biopsy because of the risk of [[hemorrhage]]
((Oppido PA, Fiorindi A, Benvenuti L, et al. Neuroendoscopic biopsy of ventricular tumors: a multicentric experience. Neurosurg Focus 2011. http://thejns.org/doi/full/10.3171/2011.1.FOCUS10326DOI))
((Talamonti G, D'Aliberti G, Debernardi A. Intracranial tumors: treatment with endoscopic neurosurgery. In: Hayat E, editor. ed. Tumors of the central nervous system. Berlin: Springer, in press. doi:10.1007/978-94-007-7217-5_19)).

The importance of pathological confirmation should be carefully weighed up in comparison with the theoretical risks of deciding chemotherapy and radiotherapy basing only on neuroradiological findings
((Nicholson JC, Punt J, Hale J, et al. Germ Cell Tumour Working Groups of the United Kingdom Children's Cancer Study Group and International Society of Paediatric Oncology: neurosurgical management of paediatric germ cell tumours of the central nervous system—a multi-disciplinary team approach for the new millennium. Br J Neurosurg 2002;2013:93–5))
((Kanamori M, Kumabe T, Tominaga T. Role of histological diagnosis of germ cell tumor in the pineal region. In: abstracts for the second International Symposium on central nervous system germ cell tumors. Neuro Oncol 2005;2013:513–33)).

===== References =====