CNS 18 - 16 
6.1 Neuroimaging Evaluation 
MRI, including dynamic contrast-enhanced MR imaging (DEMRI), will be 
performed to access tumor response and to monitor for imaging evidence of 
neurotoxicity (inflammation, hemorrhage). DEMRI is an investigational 
analytical assessment of metabolic activity in and around the tumor-bone upon the 
time-related appearance of contrast. See Protocol Appendix III. 
Magentic resonance spectroscopy (MRS) is a rapidly evolving science that 
correlates measurable biochemical concentrations with metabolic changes within 
treated tumors and peritumoral brain. See Protocol Appendix III. 
6.2 Yearly Follow-up Laboratory Evaluation 
In addition to standard and investigational studies, patients will be followed once 
a year for 14 years for retroviral gene transfer safety monitoring. Studies will 
include CBC with differential and platelet count, and PCR on mononuclear cell 
DNA for vector sequences (2 ml heparinized peripheral blood. Send to GTI, 
Gaithesburg, MD.) 
6.3 Autopsy 
An attempt will be made to perform a complete autopsy on any patient who dies 
during the study. Whenever possible, tissues from the brain, tumor(s), bone 
marrow, will be evaluated for the presence of the GITKSVNa vector by PCR. 
Such specimens will be frozen at -70° and sent to GTI, Gaithersburg, MD. 
Whenever the autopsy is performed outside SJCRH, an attempt will be made to 
obtain tissue and pathological slides of the CNS for review. 
7.0 EVALUATION CRITERIA 
NO RESPONSE: 
PARTIAL RESPONSE: 
COMPLETE RESPONSE: 
8.0 TOXICITY MONITORING 
Toxicity will be monitored and graded according to the NCI Common Toxicity Criteria 
(see attached). Unacceptable toxicity is defined as a) any Grade III/IV major end organ 
toxicity and b) any irreversible cerebral dysfunction (motor, sensory, cognitive), or 
injury not clearly related to neurosurgery or not present prior to study enrollment. 
Toxicity due to ganciclovir therapy and/or neurologic complications due to CNS tumor 
itself and/or its progression, will not be considered as unacceptable toxicity. 
In the event of Grade III/IV major end organ toxicity or unique or unexplainable events, 
an adverse drug report (ADR) report will be filed. The St Jude Children Hospital IRB, 
and the principal investigator(s) at the Surgical Neurology Branch, NIH, will be notified. 
<50% decrease in size or progression of the tumor by 
MRI scan. 
>50% and <100% decrease in tumor volume on MRI 
scan. 
No remaining tumor on MRI at 3 months. 
Recombinant DNA Research, Volume 18 
[319] 
