extra extra

Question 1

medulloblastoma

Answer 1

• cerebellum - dogs, cats, cows and pigs
• mestastsize via CSF
• macro = well circumscribed, soft, without bleeding
• micro = highly cellular neoplasia, roung/elongated nuclei and small amount of cytopalsm
• origin primitive neuroepithelial cells of the roof oof 4th brain ventricle

Question 2

embryonal/primitive neoplasia

Answer 2

• exceptionally rare (described in primates and calves)
• affected young animals show aggressive biological behaviour
• originate = primitive embryonal stem cells
• malignant rhabdoid tumour - subcutis, muscle + brain -> dogs and cats

Question 3

choroid plexus papilloma + carcinoma

Answer 3

• dogs (5-11yr), horses + cattle
• in 4th, 3rd and lateral ventricles
• papilloma = well circumscribed, white to red -> very similar to normal choroidal plexus
• carcinoma = invasive, increased mitosis, metastasise inside ventricular system of subarachnoid space

Question 4

astrocytoma

Answer 4

• classified according to degree of differentitation
• most common = dog (5-11yr), brachiocephalic, rare in cats
• most common location = cerebral hemisphere
• micro = large difference in appearances, specificity = tumour cells arranged around BV

Question 5

oligodendroglioma

Answer 5

• dog (5-11yr, brachycephalic), cat and cattle
• most common neuroectodermal neoplasia of CNS
• white matter
• macro = well restricted grey/pink, soft and creamy
• micro = highly cellular, expressed nucleus

Question 6

ependymoma

Answer 6

• rare of dog, cat, cattle and horse
• lateral most common, rare in 3, 4th ventricle and central canal of spinal cord
• metastasise via CSF and subarachnoid space
• macro = large with clear edges, soft and grey whithe
• micro = well vascularised, cellular

Question 7

meningioma

Answer 7

• most common mesodermal neoplasm
• older, esp cats, over 10 year, dog 7-14 yr
• cat: tela choridea, surface of hemisphere and cerebellum
• dog: brain-base, cerebellum…
• origin = arachnoidal on outer surface