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Burkitt's
lymphoma
Burkitt's
lymphoma (or
"Burkitt's
tumor", or
"Malignant
lymphoma,
Burkitt's
type") is a
cancer of
the
lymphatic
system (in
particular,
B
lymphocytes).
It is
associated
with the
Epstein-Barr
virus, also
the cause of
mononucleosis
as well as
other
cancers. It
is named
after Denis
Parsons
Burkitt, a
surgeon who
first
described
the disease
in 1956
while
working in
equatorial
Africa.
Children
affected
with the
disease
often also
had chronic
malaria
which is
believed to
have reduced
resistance
to the
virus. This
is known as
classical
African or
endemic
Burkitt's
lymphoma.
Disease
characteristics
include
large tumors
in the
facial or
abdominal
regions.
Outside of
central
Africa, a
type of
non-Hodgkin
lymphoma is
found where
cancer cells
have a
similar
appearance
to the
cancer cells
of classical
African or
endemic
Burkitt's
lymphoma.
This
condition is
known as the
non-African
or sporadic
type of
Burkitt's
lymphoma.
Again it is
believed
that
impaired
immunity
provides an
opening for
development
of the
Epstein-Barr
virus.
Examination
of
chromosomes
in this
tumor shows
translocation
of the myc
gene with an
Ig gene is
seen in this
lymphoma,
commonly (t:
8;14).
Microscopy
Consists of
undifferentiated,
small,
noncleaved
cells in
broad sheets
of tumor
cells.
Burkitt's
lymphoma
demonstrates
starry sky
appearance
due to the
macrophage
ingestion of
tumor cells.
Malignant B
cell
characteristics
Malignant B
cells have
identical
DNA
recombinations
of the V(D)J
region of
the
Immunoglobin
genes. This
means that
no increase
in
specificity
of Antibody
molecules is
occurring in
the
malignant
cells. These
malignant
cells are
thus clonal
populations
and can be
assayed for
by using DNA
probes
specific for
the regions
where
recombination
is expected.
Normal DNA
will be
characterized
by two high
concentration
of identical
germ line
DNA V(D)J
regions and
endless,
likely
undetectable,
non-germline
Ig V(D)J
DNA.
Lymphoma
cells have
an
additional
high
concentration
of V(D)J DNA
that is
unlike the
germline,
indicating
clonal
populations
of B Cells
that are not
undifferentiated
B Cells (Germline
DNA cells).
Assays
typically
use the
process of
Electrophoresis
and southern
blot
analysis to
determine
the
existence of
these
characteristics.
Treatment
Effect of
the
chemotherapy,
as with all
cancers,
depends on
the time of
diagnosis.
With faster
growing
cancers,
such as this
one, the
cancer
actually
responds
faster than
with slower
growing
cancers.
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