Are there any new or emerging diagnostic tests for chronic lymphocytic leukemia that may be helpful in the future?

We're actually very lucky
to have now some good precedent with this

very fancy diagnostic prognostic test

called MRD testing
or molecular residual disease testing.

And there's a few versions
of that test. Mostly,

we use a version called clonoSEQ,
which probably has the best precedent.

And this is an extremely fancy way
of detecting

even the tiniest amount of CLL left
in the patient's blood after therapy.

So the most common way that we use it is
we sort of use the test once prior

to starting a therapy

and then once maybe at 6,
and especially 12 months into the therapy.

In fact, we mostly use it a particularly
with one therapy called venetoclax,

which we usually use in combination
with an immune therapy,

because venetoclax has been shown
to get a good number of patients,

the majority of them to be
we say MRD negative

molecular residual disease negative.

You can't even see
the tiniest bit of CLL in their blood.

We don't want to confuse that
with cure per se,

because there could even below
the threshold of the test still be

something left in a patients
might eventually relapse,

but patients have become pretty negative
by that test have a very good prognosis

and they seem to stay in remission
for years.

So we're very grateful
to have that new test

which has been around for a few years,
but really getting implemented,

especially over the past couple of years.

One test that is exciting and relatively new

is minimal residual disease
testing or MRD testing.

So this is a highly specialized test
that helps detect small amounts of cancer

cells that may remain in the body
after treatment or during remission.

Even this is a highly sensitive test
that helps in detecting residual cells

that remain after therapy,

that are not otherwise detected
by standard clinical or laboratory tests.

So the MRD testing can be valuable in

understanding the depth of response
to treatments and also in

predicting the chance of relapse
or recurrence of disease in the future.

It can provide valuable information
on the effectiveness of the treatment

and also determining for the treatment
approaches in patients with CLL.

MRD testing in CLL
typically performed using a flow cytometry

or by molecular genetic tests
such as

a polymerase chain reaction, PCR 
or next generation sequencing or NGS.

These methods target specific genes

or immuno phenotypic signatures
that are unique to CLL cells.

By detecting and quantifying these markers
in the blood and bone marrow,

MRD testing can help in determining the
presence or absence of residual disease.

So the results of the MRD tests
are reported as the number of residual

cells for a given number of normal cells
reported as a ratio or a percentage.

So a lower MRD test would indicate

better control of disease
or a lower chance of relapse

versus a higher MRD test would indicate
a higher chance of relapse

or recurrence of disease.

MRD testing can be

very useful in CLL as this disease
is characterized by a good degree

of heterogeneity, and patients
can have varying responses to treatment.

So by providing a more accurate assessment
of the treatment response,

the MRD testing can help determine
the sequence of next therapies

and thus really develop a personalized
treatment decision making for a patient.