That has been around since 1997.  For more information and as to what type
of cancers can be treated do a Google search  ("prostate Cancer" Seeds).

I personally know two who have had the treatment in the past year,
apparently with satisfactory results.

One (75 years old) said his doctor (a Siamese native) told him that it was
"Cold as an Icicle".  When he told the doctor he wished it was hard as one,
the Dr. didn't even smile.

Radioactive stuff like that goes to where blood pools a little and kills the
area. They used to, in 1984, use a radioactive isotope to kill the thyroid
for that reason in people with overactive thyroids (Graves disease, not
goitre).

I don't much think having a "glow stick" in the dark for a dick is a great
idea.

What I actually HAVE heard that stops melanomas and looks like stopping
other cancers is the common cold pitted against a cancer. It seems to act
like a radioactive explosion in that it goes around the body killing off
other melanomas and of course the person may get a cold but that's better
than cancer. Maybe you should try and find details of that treatment on the
web.

its been around a while.  i think its called brachy therepy.