Pineal Region Tumors
- pineal
gland consists of APUD cells and astrocytes; calcified by 16 years;
receives sympathetics from superior cervical ganglion which increase
melatonin; inhibits gonad development and regulates menstrual, adrenal,
thyroid function
- Pinealocytoma
- 30
years, M=F
- pineocytomatous
pseudorosettes
- Better
prognosis if neural or astrocyte differentiation
- Those
with neuronal differentiation are more benign and occur in older patients
- Pinealblastoma – PNET
- Small
round blue cell tumor which is equivalent to the PNET or medulloblastoma
- Highly malignant,
may seed CSF pathways
- Rx:
Surgical excision and XRT
- Prognosis:
55% of 5-year survival
- Germ
Cell Tumor
– most common
- 10-20
years
- pineal
most common location (also occurs suprasellar, third ventrical, posterior
fossa, mediastinum, retroperitoneum)
- Germinoma – most common (2/3 germ cell
tumor), 40% pineal tumors
- 10-30
years, M>F, 10% found in both pineal and suprasellar
- Equivalent
to seminoma and dysgerminoma in gonads
- large
polygonal cells without necrosis or hemorrhage
- T-cell
infiltrate with follicles
- Iso
T1, hyper T2, hyper CT, enhances
- Beta-HCG+
- Precocious
puberty in males
- Malignant,
invasive, may seed CSF pathways
- Rx:
Surgical excision and XRT
- Prognosis:
67% of 5-year survival
- Non-Germinomatous
Germ Cell Tumors
- Embryonal
carcinoma –
frequently necrosis and hemorrhage; secretes AFP and beta HCG
- Yolk
Sac Tumor (endodermal sinus) – young patients, Schiller-Duvall bodies, secretes
AFP
- Choriocarcinoma – can be primary or
metastatic, hemorrhage very common due to thin walled vessels; stains
with bHCG
- Highly
malignant, may seed CSF pathways
- Rx:
Surgical excision, XRT, ± chemo
- Prognosis:
<2 year mean survival
- Teratoma – 15% of pineal tumors,
M>F
- Mainly
benign tumors composed of components of all three embryonal layers
- May
have malignant components with poor prognosis
- Others – Astrocytoma, anaplastic
astrocytoma, GBM, ependymoma, meningioma, metastasis
- Follow
same course as in other regions of the brain