Nervous System Flashcards
What are the top 3 primary brain tumours in the dog?
- meningioma (45%)
- glioma (40%)
- choroid plexus tumours (5%)
What are the most common secondary brain tumours in the dog?
- hemangiosarcoma 29-35%
- pituitary tumours 11-25%
- lymphoma 12-20%
- carcinoma 11-20%
The above compromises 77-86% of all secondary brain tumours
Which breeds are predisposed to meningiomas?
Golden, boxers, min Schnauzers, rat terriers
What is the most common intracranial tumour in the cat?
meningioma (>50%)
the majority (70%) of intracranial tumours = primary
What are the most common secondary brain tumours in the cat?
lymphoma 50%
pituitary 30%
How likely will see a dog/cat with seizures?
50% of dogs with forebrain lesions
25% of cats with brain tumours
What clinicals signs are seen with brainstem lesions?
central vestibular dysfunction
What is the most common clinical sign of intracranial lesion in cats?
abnormal behaviour (16-67%)
non-specific signs (lethargy, decreased in appeite) –> 20% of cats with brain tumours (also in dogs with pituitary tumours)
in one study:
73% behavioural/ mentation changes
68% cranial nerve deficits (ex. nystagmus)
59% gait abnormalities
only 11% presented solely for seizures
Characteristics and outcomes for 61 cats that underwent either surgery or stereotactic radiotherapy as treatment for intracranial meningioma (2005–2017). Tichenor et al 2023
How often can cats have multi-focal meningioma?
20%
How often can secondary tumours be detected on staging for dogs with brain tumours?
3-23%, chest or abdomen
but only 8% resulted in a change in treatment
What’s the accuracy of diagnosing brain tumours for dogs based on MRI?
around 70% of dogs, up to 100% for meningioma
What is a feature of glioma on MRI?
ring enhancement
cannot accurately assess the subtypes or grade though
- but one study did find moderate-to-marked contrast enhancement and a ring pattern were present in OG III but not in OG II, indicating that certain MRI features reflect histological grading in dogs (Ampimaque et al 2022)
- oligodendrogliomas were associated with smooth margins and T1-weighted hypointensity compared to astrocytomas and undefined gliomas. They were also more commonly in contact with the ventricles than astrocytomas (Jose-Lopez et al 2021)
Grading of oligodendroglioma in dogs based on magnetic resonance imaging. Amphimaque et al 2022
Clinical features, diagnosis, and survival analysis of dogs with glioma. Jose-Lopez et al 2021
What’s the risk and accuracy for brain biopsy?
with experienced clinicians and imaging guidance, there is ~5% of serious complications and 95% diagnostic yield
- one study with stereotactic biopsy for dogs found >185k platelet count to minimize risk of side effects (hemorrhage) and the incidence of side effects was 27% (transient exacerbation of preexisting neurologic deficits, transient new deficits, or permanent neurologic deficits) – 88% of side effects were transient.
Risk factors for adverse events occurring after recovery from stereotactic brain biopsy in dogs with primary intracranial neoplasia. Shinn et al 2020.
What’s the most common grade of meningioma in the cat? in the dog?
cat = grade I
dog = grade II (~40%), but all grades can invade into the parenchyma
What is the most common type of glioma in the dog and cat?
oligodendroglioma
Can the grade of choroid plexus tumours be assessed on MRI?
yes, based on intraventricular or subarachnoid metastasis
What are the distribution of grades of choroid plexus tumours in dogs?
grade 1 = choroid plexus papilloma - 40%
grade 3 = choroid plexus carcinoma - 60%
grade 2 not reported in the dog
Can CSF differentiate between neoplastic vs non neoplastic?
the CSF is often abnormal but can be difficult to distinguish between neoplastic vs. not
Which tumours can be diagnosed with CSF more readily?
- choroid plexus carcinoma (>80mg/dL of protein)
- LSA, histiocytic sarcoma (52% diagnostic rate according to Rossmeisl et al 2020)
- cats with caudal brainstem oligodendroglioma
What’s the MST for palliative treatment for intracranial tumours?
around 9 weeks
25 weeks if supratentorial
13 weeks if infratentorial
Pituitary = 51 weeks
Which chemotherapies are commonly used for intracranial tumours?
CCNU, temozolomide, hydroxyurea
What’s the MST with CCNU for intracranial tumours?
MST = 93 days
(palliative = 60 days)
What is the MST for VMAT +/- temozolomide?
420 days (with temozolomide)
383 days (without temozolomide)
What’s the outcome for surgery for feline meningioma?
MST > 2 years (23-37 months)
25% recurrence rate (3-69 months)
preferred tx option for cats with supratentorial meningioma
What’s the outcome for surgery for canine meningioma?
MST = 7 months
with ultrasonic aspirator or other techs that help with intraop visualization = 16-70 months
with radiation to follow = 16-30 months
What is the complication rate and what kind of complications can be expected with intracranial surgery?
11%
aspiration pneumonia, intracranial hemorrhage
What’s the outcome for RT for canine meningioma?
generally MST 7-23 months
extra-axial (likely meningioma = 9-19 months)
Intra-axial (ex. glioma) = 9-13 months
What’s the outcome for surgery + RT for canine meningioma?
16-30 months
How does VEGF expression and progesterone expression effect outcome of intracranial tumours?
VEGF:
> 75% MST 15m
< 75% MST 25m
Progesterone
< 24% - 2y survival rate of 91%
> 24% - 2y survival rate of 42%
What’s the treatment choice of pituitary macroadenoma?
RT
What are some negative prognostic factors for pituitary macroadenoma?
severe neurological dysfunction
relative large size
What is the distribution based on anatomical location of spinal tumours?
- extradural 50%
- intradural/ extramedullary 35%
- intramedullary 15%
What is the most common spinal tumour in the dog/cat?
meningioma
What is the most common primary and secondary intramedullary spinal tumours in the dog?
primary = ependymoma, glioma
secondary = hemangiosarcoma, iUC
What is the most common feline spinal tumour?
LSA = 2nd most common spinal cord disease in the cat and the most common feline spinal tumour (85% are secondary from multicentric LSA)
LSA can be in any spinal cord compartments
What is syringomyelic syndrome?
changes in neurological modulation due to destruction of the grey matter in the dorsal horn
How common is paraspinal hyperpathia in dogs?
68% of dogs with intramedullary tumour
Which round cell tumours can cause osteolysis of the spine?
LSA and plasma cell
Which IHC can be used for canine nephroblastoma of the spinal cord?
WT-1
Which breeds are predisposed to nephroblastoma of the spinal cord?
young (<3y) German Shepherds and gold retrievers
What’s the phenotype of primary CNS LSA and secondary LSA in the dog?
Primary CNS lymphoma - only reported in the spinal cord = diffuse large B cell (CD79a +)
Secondary spinal LSA:
55% B cell, 45% T cell
What’s the utility of CSF in spinal cord tumour diagnosis?
sensitive, but not specific, often non-diagnostic (unless it’s LSA)
What’s the outcome of chemotherapy for spinal cord tumours?
- ideal protocol for LSA is unknown
- platinum based chemo generally used for OSA
What’s the outcome of cats treated with vincristine, cyclophosphamide, and prednisone for spinal LSA?
50% response rate with 14 weeks of remission
What’s the outcome of surgery for spinal cord tumours?
Canine meningioma
MST 6-47 months, with RT up to 45 months
Feline meningioma
MST = 6-17 months
can be good for acute decompression/ palliation
What’s the MST for vertebral tumours?
dog MST = 4.5m
cat MST = 3.7m
What’s the outcome of surgery for neophroblastoma?
variable
Sx alone 71-374 days
intradural/extramedullary = 380 days
intramedullary = 140 days
Which species (cat or dog) can have more benign peripheral nerve sheath tumours?
cats
all canine PNST behave aggressively
What phenotype is more common for feline/ canine peripheral nerve LSA?
cat = usually B cell
dog = usually T cell
What are some differentials for PNST?
neuritis, hypertrophic ganglioneuritis, peripheral nerve LSA
What’s the surgical outcome for canine PNST?
MST = 6m
with complete resection MST 1303 days
What’s the RT outcome for canine PNST?
VMAT MST = 8m
What’s the surgical outcome for canine trigeminal nerve sheath tumour?
SRS/SRT MST = 175/ 441 days
RT is better at resolving neurological signs than surgery for those with brainstem involvement
(this tumour often has insidious onset and even untreated can live for 18m)
What’s the out come of canine vertebral OSA treated with surgery +/- adjunctive therapy?
Sx only MST = 42 days
with chemo and RT = 261 days
Sx + RT MST = 101 days (one dog)
Sx + chemo (carbo based) MST = 82 days
Surgical decompression, with or without adjunctive therapy, for palliative treatment of primary vertebral osteosarcoma in dogs. Dixon et al, 2019.
What’s the outcome of CFRT for young dogs with spinal nephroblastoma?
- post-op setting
- 45-50 Gy in 18-20 fractions
- MST = 1234 days (due to any cause)
Conventional fractionated radiotherapy outcomes for young dogs with nephroblastoma of the spinal cord: 5 cases. Kim et al 2023
What’s the outcome of dogs/cats treated with solitary ventricular tumour treated with RT +/- shunt?
MST = 162 days RT alone
MST = 1103 with ventriculoperitoneal shunting
Solitary intraventricular tumors in dogs and cats treated with radiotherapy alone or combined with ventriculoperitoneal shunts: A retrospective descriptive case series. Beckmann et al 2023
What’s the outcome of SRT for canine glioma?
Trageser et la 2023:
MST = 349 days
disease specific survival = 413 days
91% showed improvement in clinical signs post RT
Moirano et al 2020 (cyberknife):
MST = 636 days (one course 258 days, multiple = 865 days), with chemo (CCNU, temozolomide, hydroxyurea, Palladia) = > 658 days
Debreuque et al 2020 (CFRT, 15 x 3Gy over 5 weeks):
MST = 698 days
Efficacy of stereotactic radiation therapy for the treatment of confirmed or presumed canine glioma. Trageser et al 2023
Efficacy of frameless stereotactic radiotherapy for the treatment of presumptive canine intracranial gliomas: A retrospective analysis (2014-2017). Moirano et al 2023
Definitive-intent uniform megavoltage fractioned radiotherapy protocol for presumed canine intracranial gliomas: retrospective analysis of survival and prognostic factors in 38 cases (2013-2019). Debreuque et al 2020
What is Leptomeningeal gliomatosis and which breed is commonly affected?
- Leptomeningeal gliomatosis (LG) is characterized by the dissemination of neoplastic glial cells in the subarachnoid space, either as primary LG (PLG) or secondary LG (SLG).
- 90% = brachycephalic
-all gliomas = oligodendrogliomas
Primary and secondary leptomeningeal gliomatosis in dogs. Rissi et al 2024
What’s the outcome for intraventricular brain tumours treated with SRT?
MST = 16.9m (n =11)
2 dogs with carcinoma lived for 24 and 133 days respectively
Stereotactic radiotherapy outcomes for intraventricular brain tumours in 11 dogs. Hansen et al 2023
What’s the outcome of dogs with intracranial tumour treated with a boost CFRT protocol?
TTP:
control = 828 days
Boost = 627 days
MST:
control = 724 days
Boost = 557 days
no significant differences
Treatment of intracranial neoplasia in dogs using higher doses: A randomized controlled trial comparing a boosted to a conventional radiation protocol. Staudinger et al 2022.
What’s a prognostic feature for canine glioma?
Mitotic count
What’s the outcome of canine gliomas?
this study was Sx + autologous vaccine (Merickel et al 2021)
astrocytic tumors - MST = 743 days,with oligodendroglial - MST = 205 days
undefined tumors - MST = 144 days,
low grade glioma - MST = 734 days
high grade glioma - MST = 194 days
This one include a combo of Sx, RT and/ or chemo (Jose-Lopez 2021)
MST = 84 days vs palliative only = 26 days
Prognostic histopathologic features of canine glial tumors. Merickel et al 2021
What’s the outcome of cyberknife SRT for primary intracranial tumours in dogs?
- the median PFI was 347 days
- MST = 738 days
Cerebrum > brainstem > cerebellum for PFI
meningioma»_space;> others
CyberKnife stereotactic radiotherapy for treatment of primary intracranial tumors in dogs. Carter et al, 2021
What’s the outcome for presumed canine meningioma treated with SRS?
SRS: MST - 519 days, infratenorial tumour = shorter ST
Single fraction stereotactic radiation therapy (stereotactic radiosurgery) is a feasible method for treating intracranial meningiomas in dogs. Kelsey et al 2018.`
Which breeds have predominately primary / secondary CNS histiocytic sarcoma?
Primary: Corgi and Shelties
Secondary: Rottweilers (exclusive secondary only)
Predisposed breeds: Berners, Golden, Rotties, Corgis, and Shelties
Clinicopathological characteristics of histiocytic sarcoma affecting the central nervous system in dogs. Toyoda et al 2020.
What’s the outcome of canine primary CNS histiocytic sarcoma?
brain: ST < 145 days
spine: < 77 days
Clinicopathological characteristics of histiocytic sarcoma affecting the central nervous system in dogs. Toyoda et al 2020.
What’s the MST for canine histiocytic sarcoma of the CNS?
+/- Sx - MST = 58.5 days
+/- RT - MST = 74 days
+CCNU - MST = 97 days
Clinicopathological characteristics of histiocytic sarcoma affecting the central nervous system in dogs. Toyoda et al 2020.
How well does RT control seizure in dogs with brain tumours?
The duration of seizure freedom 24m (RT group) vs 1.7 m (medical therapy)
MST = 34.6 months vs 6.2 months
Effect of radiotherapy on freedom from seizures in dogs with brain tumors. Monteiro et al, 2020
What’s the outcome of canine macroscopic brain tumours treated with IMRT?
MST = 18 months
Definitive-intent intensity-modulated radiation therapy provides similar outcomes to those previously published for definitive-intent three-dimensional conformal radiation therapy in dogs with primary brain tumors: A multi-institutional retrospective study. van Asselt et al 2020
What’s the complication rate of cranial surgery for cats and dogs?
Mortality rate of 14.5%
Complication rate 35.2% – hypotension, anemia , neuro deficits, seizures, and aspiration pneumonia
Long-term complication rate = 39.4%
What’s the outcome of Sx or SRT for cats with meningioma?
Surgery MST = 1345 days; median time to progression = 1183 days
SRT MST = 339 days; median time to progression = 315 days
but surgery had significantly more complications than SRT
MST = 612 days even with herniation (Kouno et al 2020)
Characteristics and outcomes for 61 cats that underwent either surgery or stereotactic radiotherapy as treatment for intracranial meningioma (2005–2017). Tichenor et al 2023.
Surgical treatment of rostrotentorial meningioma complicated by foraminal herniation in the cat. Kouno et al, 2020.
What’s the most common complication of surgery for feline meningioma?
anemia 54%
decreased appetite
hypokalemia
Characteristics and outcomes for 61 cats that underwent either surgery or stereotactic radiotherapy as treatment for intracranial meningioma (2005–2017). Tichenor et al 2023
