425 426 appendix b r selecled essoys for anolysis

425

426
Appendix
B
r
Selecled Essoys
for Anolysis
Were the sites
independent or linked
to one another? Further testing was
required.
But
at
the end of these
inquiries
it
remained the
opinion of the team and
particularly
the clinic's pathologist that the
cancer sites
involved identical
(metastasized)
cells.
Through this diagnostic process we
learned
that
the
judgment
of whether the cancer
had metastasized
was
based
on
judgments
of
visual
similarity. There appeared to be
no
"gold standard"-no
clear means
to
check
the
reliability of
the pathologist's
judgments. In
addition, we learned
that lung
cancer
with multiple
sites
in
the
lung
was
quite exceptional.
No
one was sure
that
such a diagnostic appearance
meant
metastasization.
Using cancer
textbooks, Medline, and an
article
in
the Scientific
Ameican, we
came
to the conclusion that the
initial
diagnosis
was
not well validated. We noted
that
the
pathologists disagreed
about the
cell
type, though the
new pathologist assured
me
he
was "90o/o
certain" that the
cells
were
identical and hence had the same source.
But
knowing there
was
no
"gold
standard,"
I
was aware
that this
"90o/o"
figure
was
just
a
subjective assessment
of confidence and
not
a
real
measure of
reliability. Based
on
my wife's reading about
DNA testing
in
a
colon and
brain
cancer study
in
the
Sci-
entific
Americar we
asked
why
DNA
testing
wasn't being done
in this
case.
For rea-
sons
still
unclear, the doctors at
the cancer agency
had not
used such
procedures
in
lung
cancer cases.
They
now
do.
When they used
DNA
testing on
my sister-in-law's
lungs,
it
became clear
(to
the amazement
of the
pathologist) that the
separate sites
were
not
from
the same source,
but
independent. The cancer had
not metastasized
and the
risk of
an
operation to remove the cancer was
iustified-it is
over four years
since her
operation and my sister-in-law
remains cancer free.
I
believe
that
the above
story is
(among other things) an educational
success
story. Our
actions
and reflections embodied the
ideal
of
a
liberal education:
intel-
lectual
autonomy.