CNS Cancer
Mark S. Schnitzer, M.D.
Center For Neurological Surgery
www.neuroservices.com
Brain Tumors
Mark S. Schnitzer, M.D.
Participants will Learn…
Diagnosis & Treatment of Patients
with Brain Tumors
Current Therapy
Future Directions
Agenda
Overview
Making the Diagnosis
Primary Brain Tumors
Metastatic Brain Tumors
Available Treatments
Future Directions
Overview
100,000 new brain tumors/year
Second leading cause of cancer death
in children & young adults
Second fastest growing cause of
cancer death among those over 65
No behavioral change has been shown
to reduce risk
Diverse group of neoplasms
Making the diagnosis…
Symptoms
Increased ICP
Focal irritation or disruption of
brain function
Immediately raise suspicion…
Usually not BT, but may be…
Imaging studies
Biopsy
Symptoms that immediately raise suspicion…
New seizure in an adult
Gradual loss of movement or sensation
in an extremity
Unsteadiness/imbalance, especially
w/HA
Loss of vision, especially peripheral
vision
Double vision, especially w/HA
Hearing loss
Speech difficulty of gradual onset
Symptoms that are probably not BT but may be…
Headache
Most common symptom of BT
Worrisome if…
Steady HA, Worse in AM
Persistant HA associated with N/V
Associated with diplopia,
weakness, or numbness
Change of behavior
Infertility or amenorrhea
Imaging studies
Computerized tomography (CT)
X-ray
Contrast
Magnetic resonance imaging (MRI)
Magnetic field (not X-ray)
Multiplanar
Contrast
Spectroscopy
Positron Emission Tomography (PET)
Primary Brain Tumors
Benign
Malignant
Current classification…
Future classification according to
genetic alterations possible
Primary Brain Tumors (cont.)
Gliomas
Astrocytomas
Well Differentiated
Anaplastic
Glioblastoma Multiforme
Ependymoma
Oligodendroglioma
Ganglioneuroma
Mixed Glioma
Brain Stem Glioma
Optic Nerve Glioma
Primary Brain Tumors (cont.)
Chordoma
Choroid Plexus Papilloma
Chraniopharyngioma
Meningioma
Pineal Tumors
Pituitary Tumors
Primitive Neuroectodermal Tumors
Schwannomas
Vascular Tumors
Primary Brain Tumors (cont.)
MRI scan (with Gd)
Glioblastoma multiforme
Primary Brain Tumors (cont.)
MRI scan (with Gd)
Meningioma
Primary Brain Tumors (cont.)
MRI scan (with Gd)
Pituitary Macroadenoma
Metastatic Brain Tumors
Often multiple
Most common sources:
Lung
Breast
Colon
Kidney
Melanoma
2/3 of mets will produce symptoms at
some time during the life of the patient
Metastatic Brain Tumors (cont.)
MRI (with Gd)
Mets from lung CA
Available Treatments
Surgery
Radiation Therapy
Chemotherapy
Other Therapies
Surgery
Techniques for tumor localization
New surgical tools
Collaborative efforts
Electrophysiological mapping
Local anesthesia
Delivery of novel treatments
Local chemotherapy (Gliadel Wafers)
Gene Therapy
Surgery (cont.)
Surgery (cont.)
Radiation Therapy
Traditional radiation therapy
Hyperfractionation
Radiosensitizers
Stereotaxis
Radiosurgery
Radiotherapy
Interstitial brachytherapy
Boron neutron capture therapy
Radiation Therapy (cont.)
Radiation Therapy (cont.)
Radiation Therapy (cont.)
Radiation Therapy (cont.)
Chemotherapy
Oral
Temodar (temozolomide)
IV
Combinations
Procarbazine, CCNU and Vincristine,
Also known as PCV
Intermission
On the Horizon…
Unfettered growth of tumor cells
requires a hospitable environment
Inhospitable environment induces
tumor survival strategies
Stop dividing and conserve energy
(G0 state)
Stimulate growth of new blood
vessels (Angiogenesis)
Seek more hospitable environment
(Invasion)
Death of a few for the good of the
many (Apoptosis, programmed cell death)
Angiogenesis Inhibitors
Tumor nodule is unable to grow beyond
a few millimeters in diameter until penetrated by new capillaries
Drugs and antibodies to block
endothelial growth factor receptor and/or fibroblast growth factor receptor
Protease (Invasion) Inhibitors
Higher grade of malignancy, higher
level of proteases
Also have antiangiogenic properties
Activation of Tumor Cell Apoptosis
DNA-damaging, cytotoxic drugs.
Drugs that effectively interfere with
important signaling pathways to effect apoptotic cell death with fewer
systemic toxic effects.
Differentiating agents
Change the malignant tumor phenotype
to a less malignant phenotype
cytostasis, not death
Immunotherapy
Inducing a systemic antitumor
response that carries immune effector functions into the CNS
Mammalian brain can be
stimulated to evolve into an "immunologically
active"
organ thereby allowing for a primary immune response in the brain
Gene therapy
Transfer of genetic material into
mammalian cells with the aim of eliciting a theraputic response
Problem is not what should be
delivered into the tumor cells, but rather how to deliver the gene into all
the tumor cells
Local delivery à
localized effect à no survival benefit
Combination Therapy
Gliomas are constituted by a
heterogeneous mixture of cancer cells
Several agents with different
mechanisms of action (apoptosis, antiangiogenic, immunogenic…etc) would
probably be necessary to kill a wide spectrum of cancer cells
Coexpression of multiple genes may
induce additive or synergistic effects
Summary of Treatment Costs for GBM and AA
Where to Get More Information
Mark S. Schnitzer, M.D.
(714) 525-7177
www.neuroservices.com
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