18.0 INFORMED CONSENT 
YouA'our child are currently in remission of acute myelocytic leukemia (AMt). However, 
we know from previous experience that there is about a 65% chance that the leukemia will 
return, when the leukemia cells will be resistant to the best drugs used in first treatments. 
Because we would like to prevent this from happening we are proposing that we give 
you/your child high dose chemotherapy which we hope will destroy any remaining leukemic- 
cells. Because this treatment damages the normal marrow, we will follow the chemotherapy 
by giving back you/^our child’s own bone marrow, which has been marked to enable us to 
follow how well it grows and - in the event of relapse of disease - to learn if malignant cells 
in the marrow contributed. 
Purpose 
The treatment we are now planning is designed to kill greater numbers of leukemia cells 
early in the treatment, resulting in longer periods of remission (absence of any signs or 
symptoms of AML). Two highly effective drugs will be given to you/your child in very high 
doses. This therapy will destroy most of your/^our child’s blood cells, including the normal 
cells needed to combat infection and control bleeding. 
To prevent fatal complications from this high-dose chemotherapy, we will attempt to restore 
the normal production of blood soon after drug treatment. This will be done with infusions 
of bone marrow collected and treated at the time you or your child was in complete 
remission. 
Blood Tests for Viruses 
So that we can better measure the risks of the transplant, we will test youyyour child’s blood 
for viruses which can cause problems after the transplant. These viruses include Hepatitis B, 
which causes liver damage. Cytomegalovirus, which causes lung damage, and HIV, which 
causes AIDS. 
Marrow Marking 
Although we believe the high dose chemotherapy and bone marrow transplant will benefit 
you^our child, in many patients the leukemia returns. We do not know if this return is 
always due to malignant cells left behind in your^our child’s body after the intensive 
chemotherapy, or whether the cancer comes back because the marrow contains malignant 
cells. Nor do we know whether the marrow we given back to you really permanently 
supplies all your/your child’s blood cells or whether it acts as a temporary bridge until 
your^our child’s own marrow recovers. If we knew the answers to these questions we would 
be able to change our approach to treatment. 
A recent advance makes it possible to answer these questions. Using a method called 
retroviral mediated gene transfer we can insert a genetic marker into a small number (about 
1 in 20) of your/your child’s marrow cells before returning them to you^our child. If your 
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