BONE TUMOUR
PERFORMING A BONE MARROW TRANSPLANT
Normal bone marrow is used to replace
malignant or defective marrow. In the
allogeneic procedure, healthy marrow
is taken from a donor. In the autologous
procedure, the patient’s own healthy
marrow is used.
W ith o n e s i b l i n g
t h e r e i s a
2 5
%
c h a n c e o f f i n d i n g a
c o m p a t i b l e d o n o r .
W ith t h r e e s i b l i n g s
t h e r e a r e t h r e e
o p p o r t u n i t i e s f o r
a
2 5
% c h a n c e o f
fin d i n g a d o n o r .
Finding a donor
The more siblings one has, the greater the
chance offinding a donor. With three or more
siblings, the chances are good.
SITES OF BONE MARROW
Red or yellow in colour, bone marrow is a soft, fatty tissue
found in the cavities of bones. In newborn babies, red bone
marrow is present in all bones; during the teen years, most
is replaced by yellow marrow. The marrow used for
transplants is red.
S o ft , s p o n g y
H a rd ,
b o n e
c o m p a c t b o n e
B o n e
Bone marrow seen
m a r r o w
under the microscope
1
Before transplantation, all the recipient’s
bone marrow is destroyed by treatment
with drugs or radiation. Destroying the
marrow kills any cancer cells.
2
Using general anaesthesia, bone marrow
is aspirated from the donor's iliac crests
and/or sternum. Up to one litre is removed.
The transplanted marrow grows quickly to
occupy the bone spaces.
3
After aspiration,
the bone marrow
is transfused
intravenously into
the patient. The bone
marrow cells find their
way through the
circulation into the
patient’s marrow
cavities, where they
start to grow.
DONOR ASPIRATION
With the donor lying face down, a
hollow aspiration needle, which has a
stylet (a thin, sharp lance) within it, is
introduced into the bone (iliac crests).
The stylet is then removed. Bone
marrow is sucked out through the
cortex into a syringe connected
to the needle.
I lia c c r e s t
S t y le t
A s p ir a t i o n n e e d l e
B
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