<unk>  is a relatively rare, malignant, highly vascular neoplasm and accounts for a small proportion of all intracranial germ cell tumors. It is an aggressive tumor and has a propensity to metastasise systemically. Pure<unk>  tumors secrete β-HCG.
On microscopic histopathological analysis,<unk>  is characterized by presence of intimately related syncytiotrophoblasts and cytotrophoblasts without formation of definite placental type villi. Syncytiotrophoblasts are large multi-nucleated cells with eosinophilic cytoplasm. They often surround the cytotrophoblasts, reminiscent of their normal anatomical relationship in chorionic villi. Cytotrophoblasts are polyhedral, mononuclear cells with hyperchromatic nuclei and a clear or pale cytoplasm.<unk>  accounts for 5% of all pineal masses.
The peak age at diagnosis for<unk>  is 20-30 years.
Common complications of<unk>  include:
CSF metastasis
Intraventricular hemorrhage
Coma
Systemic metastasis
The clinical presentation of<unk>  is mainly from the obstructive hydrocephalus secondary to compression of the tectum of the midbrain and obstruction of the aqueduct. Symptoms of<unk>  include headache, vomiting, ptosis, and weakness.
Compression of the superior colliculi can lead to a characteristic gaze palsy, known as Parinaud syndrome.
Common physical examination findings of<unk>  include papilledema, signs of precocious puberty, restricted extraocular movements, sluggish pupillary light reflex, stiff neck, hemiparesis, and abducent nerve palsy.
Laboratory findings consistent with the diagnosis of<unk>  include abnormal CSF analysis, demonstrating xanthochromia.
Head CT scan and brain MRI may be helpful in the diagnosis of<unk> .
On head CT scan,<unk>  is characterized by a round, calcified, homogeneous, enhancing mass in the third ventricle associated with the dilation of the lateral and third ventricles and periventricular lucency.
On brain MRI,<unk>  is characterized by hyperintensity on T1-weighted images and signal drop-out and blooming on T2* sequences.
Biopsy is generally done to confirm the diagnosis of<unk> .
The mainstay of therapy for<unk>  is radiotherapy and/or chemotherapy. Sometimes, surgical resection may be done.
Pineal choriocarcinoma
Mixed mullerian tumor
Gonadoblastoma
Mixed Mullerian tumor
Pineal embryonal carcinoma
Endolymphatic sac tumor
Pineal germinoma
Pineal yolk sac tumor