If your child's tumor is unresectable and surgery is too dangerous 
due to its location in the brain, then vector-producing cells will be 
placed directly into the tumor using stereotaxy. For this procedure, 
your child will be put to sleep with general anesthesia, a localizing 
device will be fixed to your child's skull and a CT scan with contrast 
injection will be obtained. Using the information from the scan, 
suitable sites in the tumor will be injected with vector-producing cells 
by passing a needle through the brain into the tumor. After this 
operation, monitoring and treatment with Cyovene will proceed as 
described above. It is possible that at some time during treatment, 
your child may become a candidate for placement of an Ommaya reservoir 
into the tumor to allow for additional treatment with vector-producing 
cells. This will require a second stereotaxic operation to allow for 
placement of the reservoir into the tumor. 
Follow-up Care and Evaluation: 
After your child finishes the course of Cytovene he/she will be 
discharged from the hospital. Two weeks after discharge, he/she will 
be required to return for follow-up studies. He/she will undergo 
neurological and physical examination and laboratory test, as were 
performed before surgery. An MR or CT scan of the brain may also be 
obtained. Following the initial visit, he/she will be seen as an 
outpatient at 2-8 week intervals for the first year. The number of 
visits after the first year will depend on the status of the tumor. We 
expect that we will receive one sample of blood per year for the 
remainder of your child's life to monitor the safety of this gene 
transfer methodology. 
POTENTIAL RISKS 
Risk of MR and CT scans: 
MR and CT brain scans are painless procedures that are very safe 
for most patients. During the scan your child will lay flat in a long 
metal cylinder, which people who fear closed spaces sometimes find a 
little frightening. Patients can be observed at all times by the 
operator and can be assisted if necessary. Your child will be moved out 
of the machine if requested. The MR machine makes a thumping sound 
while operating. 
A small proportion of people develop short-lived reactions during 
the dye administration including nausea, headache, hot flashes, and 
heart palpitations. These symptoms usually resolve spontaneously within 
minutes. A smaller group of patients are actually allergic to the dye 
and develop a rash, hives, respiratory difficulty, and in extreme cases 
pulmonary and cardiac arrest and death. Your child will be closely 
monitored and if an allergic reaction develops, he/she will be promptly 
treated with epinephrine and breathing assistance if necessary. Both 
therapies are immediately available in the room where the brain scan 
will be performed. 
Patients at risk for injury from MR are those with pacemakers, 
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