After-Pop! What is Boron Neutron Capture Therapy?

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Hello there, and welcome back to
another episode of Naked

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Nuclear.
You are listening to the After

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Pop.
These short bonus episodes give

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us a chance to go deeper into
the science that comes up during

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our interviews.
I wasn't really sure if people

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enjoyed the After Pops, and I
recently got feedback from one

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of our listeners that he does
enjoy the After Pops.

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So here they are.
Today we're going to be diving

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into something that sounds like
it came out of a science fiction

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medical journal, but it's real.
It's boron neutron capture

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therapy, or BNCT.
Dr. Fiona Raymond, who you heard

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in the last episode, actually
did her PhD research in this

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exact area.
So today we're going to be

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breaking down what BNCT is, how
it works, who it might help, and

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why it's making a bit of a
comeback.

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And we're going to keep it
simple because that's the only

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way I can understand it.
What is BNTC?

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BNTC stands for Boron Neutron
Capture Therapy.

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At its core, it's a very precise
way to try and kill cancer cells

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using a mix of boron neutrons
and nuclear reactions.

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Now, I know radiation and cancer
in the same sentence sounds

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scary, but this is a targeted
therapy designed to hurt the

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tumor and spare the healthy
tissues.

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That's what makes it so
promising.

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BNTC is what we call a binary
treatment.

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That means it needs two parts to
work.

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Think of it like a key in a
lock.

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Alone, neither does anything,
but together they unlock

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something powerful.
The key is a drug that contains

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boron, a naturally occurring
element.

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The boron is specifically
designed to go directly into the

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cancer cells.
Not the healthy ones, just the

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bad guys.
So what is boron exactly?

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Boron is a chemical element with
the symbol B and the atomic

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number 5.
It's not a metal and it's not

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quite a non metal either.
It falls in the middle, so we

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call it a metalloid.
That means it has some of the

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properties of metals and some of
the properties of non metals.

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You can find boron in things
like laundry detergent, glass,

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ceramics, and even in your body
in small amounts.

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In BNTC, we use a specific type
of boron called Boron 10, which

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is really good at capturing
neutrons.

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The trick is to attach the boron
to a molecule that cancer cells

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are more likely to absorb.
So the boron acts like a Trojan

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horse, sneaking into the tumor
and what happens during the

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therapy?
So here is the magic or the

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science.
Boron 10, which is a stable

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version of boron, captures a
neutron.

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That's why it's called neutron
capture therapy.

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When it does, it becomes
unstable and splits, creating 2

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charged particles, A lithium
nucleus and an alpha particle.

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These two particles are high
energy, but they only travel

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about the width of a single
cell.

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That's incredibly tiny, about 5
to 10 micrometers.

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So what does that really mean?
It means that the damage they do

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is highly localized.
Only the cell that had the boron

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gets destroyed.
The neighboring cells stay

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healthy.
Compare that to other cancer

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treatments like generalized
radiation therapy, which can

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damage everything in its path.
BNTC is like a smart laser,

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super focused.
Now let's move over to the

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neutrons.
What are epithermal neutrons and

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a neutron beam?
A neutron beam sounds super

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scientific.
There are different types of

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neutrons based on how fast they
move.

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Thermal neutrons are slow.
Fast neutrons are really quick.

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Epithermal neutrons are right in
the in between.

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For BNTC.
We want epithermal neutrons

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because they can travel deeper
into the body than the slow

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ones, but they still slow down
enough when they hit the tissue

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to get captured by the boron.
So epithermal neutrons are

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basically the sweet spot, fast
enough to reach the tumor, but

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slow enough to trigger the
reaction.

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OK, so back to the neutron beam.
Neutrons don't just float around

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freely, we have to create them.
In BNTC, that usually means one

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of two things, nuclear reactors
or particle accelerators.

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Let's start with reactors.
These are research reactors

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designed to reduce a steady
stream of neutrons.

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The neutrons are slowed down and
focused into a beam that can be

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aimed at the patient.
Particle accelerators.

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These are newer and smaller
machines that can also produce

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neutrons by smashing particles
into a target.

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The result is a controlled
neutron beam that doesn't

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require a full scale reactor.
Both methods create a beam of

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neutrons that can be tailored
for therapy, especially with

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epithermal neutrons.
These beams are directed at the

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tumor after the boron has
already been absorbed into the

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cancer cell.
So who could benefit from

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BNTCBNTC is especially promising
for people with very hard to

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treat cancers like brain tumors,
especially head and neck

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cancers, melanomas like skin
cancers, and some type of liver

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and lung cancers.
Why these cancers?

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Often because they're hard to
operate on and they don't

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respond well to chemo or
standard radiation, they need

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something more targeted.
There's also potential for BNTC

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to help people who've already
had the maximum route of

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radiation their bodies can
safely handle.

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Since BNTC focuses damage so
precisely, it might offer them

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another option.
Doctor Raymond studied BNTC for

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her PhD and now says it's
gaining popularity.

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But why is it gaining
popularity?

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For a while, BNTC was kind of
stuck in the shadows.

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It was super promising, but
difficult to scale.

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You needed a nuclear reactor to
do it.

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Boron drugs weren't perfect and
the imaging tools weren't

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advanced enough.
But now that's changing.

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Better boron delivery agents are
being developed, ones that can

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seek out cancer more
efficiently.

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Compact neutron sources are
making hospital based BNTC more

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realistic.
And because the demand for

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precision cancer treatment is
growing, BNTC is starting to get

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more attention and funding.
In Japan, Finland, Argentina and

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Taiwan, there are already
clinical facilities operating or

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coming online.
And in the US and Europe there's

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a growing interest in using BNTC
alongside other therapies.

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So let's recap.
BNTC is a two-part therapy using

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boron and neutrons to precisely
kill cancer cells.

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It works by causing a tiny
nuclear reaction inside the

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tumor, neutrons hitting the
boron 10.

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The boron 10 becomes unstable,
splits apart and creates alpha

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particles and lithium.
Boron is a metalloid element

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that acts like a smart Trojan
horse.

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Epithermal neutrons are the
Goldilocks particles that help

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us do this safely and
effectively.

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Neutron beams are made using
reactors or particle

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accelerators.
And with newer technology,

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better targeting, and more
global research, the NTC could

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become a valuable tool in the
cancer treatment toolbox.

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Thanks for listening to the
Afterpop.

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Until next time, stay curious.