From my own personal experience (comments interspersed):

After my surgery (about three months, I think) my PSA was 0.2 and I was
ecstatic (it had been 28.4).  My surgeon didn't exactly share my enthusiasm
, however.  Three months later PSA had risen to 0.4, still pretty darned
low, I thought, but it was pointed out that it had doubled in only three
months.  For me, hormone therapy was recommended, a four-month shot of
Lupron-L.  The PSA dropped but not to zero.  Another Lupron-L shot and four
months afterward, still measurable (I forgot what).  Now radiation was
recommended.

I haven't heard of "salvage radiation."  For me, this was four years ago.

My radiation schedule took place over seven weeks, five days each week.  By
the time the program was over I was so tired that it seemed as if I were
sleeping most of the day...and night.  But the PSA is no longer measurable,
<0.1, and it's been about four years that way.  There may be side effects in
addition to lassitude.  Focusing the beam is supposed to be very precise but
it's not absolutely, perfectly precise.  There is always some possible
damage to nearby internal organs.  The position of the beam focus was
initially identified and rechecked after I was about half-way through the
therapy.

It's not exactly pleasant and it requires a part of your day, every day,
until the treatment is complete.  Forget vacation times for the period.  But
what can I say?  I worked for me.

Ken Bland

When the PSA is that low, it usually is a localized recurrence - which
is the good news inside the bad news.

You are going to go through another round of treatment, but there
is a decent chance that it will effect a cure.  If so, you'll be home
free.  If not, there's still an excellent chance that your husband will
still be there for you ten years from now, and possibly a lot longer.

A localized recurrence like this can take a long time before it
metastasizes, and another long time before it causes symptoms.
In the meantime, hormone therapy can stop the progression, possibly
for many years, and there are new therapies becoming available
that will likely stop any progression of the cancer after that.

I understand that this is terribly depressing, and it does mean that
for the next 8 weeks or so your schedules will be tied to the
radiation treatment.  But go ahead and make plans for the time
after that, and for next year, and for the year after that and the
year after that.  Plan those vacations you wanted.  You and your
husband will get to take them and will get to enjoy them.  Plan
to do those things around the house you've wanted to get done.
You'll both get to enjoy them too.

I had "regular", not salvage radiation, so I can't say whether
salvage radiation is easier, but I can say that the regular radiation
I had was not bad at all.  The main symptoms I had were rectal
itch, hemmorhoids, skin burn (like sunburn) and difficulty urinating
that caused me to get up a lot at night, but that cleared up in about
five months.  I used lots of skin lotion and Preparation H.

All in all I'd have to say that there were no debilitating side effects
or after effects - only  irritations that mostly cleared up fairly
quickly.

Other people report that they got very tired.  I fought that by
first getting in good shape and second, continuing an exercise
program during the entire period of radiation.  My running dropped
from four miles at medium speed to one mile very slowly, but
I never got so I had trouble summoning up the energy I needed
for working and living.  I continued to go to work throughout
the treatment period, just taking off time in the morning to get
the radiation done.  It usually involved about 20 minutes in the
waiting room, 10 minutes on the table, and 10 minutes to go
to the bathroom afterwards and slather myself with skin lotion
and hemmorhoid cream.

I can't answer that because I also had hormone therapy and
HDR seeding, which caused my PSA to bounce all around.  The
rad onc should be able to give you a good idea of what to expect
and some of the other people here might be able to chime in.

I think I had some loss of potency.  It's hard to say for sure
because I'm not getting a bit younger.  But I am still able to
get erections - especially with Viagra.  I am very sure that,
whatever the state of my erection, my sensitivity to stimulation
and my pleasure in sex did NOT decline.

Surgery and radiation can both damage the nerves and/or blood
vessels involved in erection.  But it is my understanding that neither
one damages the nerves involved in sexual pleasure, or interferes
with orgasm - although the ejaculate may disappear.

My personal view is that we only go around once in life.  There isn't
a reason in the world not to engage in oral sex, or anything else that
gives pleasure to two consenting adults.  Prostate cancer changes
a couple's sex life.  But it absolutely doesn't have to end it and
doesn't have to even make it any worse.

To my great surprise, I even managed to have sex while taking
hormone therapy.  I had no interest in sex at all, but once we
got started, the interest would return and I was able to fully
engage.

"...Though much is taken, much abides; and though
We are not now that strength which in old days
Moved earth and heaven, that which we are, we are,
One equal temper of heroic hearts,
Made weak by time and fate, but strong in will
To strive, to seek, to find, and not to yield."

         Alfred, Lord Tennyson
         Ulysses

Best of luck,

   Alan

I reluctantly welcome you again, this time to a more exclusive sect of the
club known as the Recurrents.

EBRT is a breeze, from my experience, if you prepare for it.  But, like all
things, it effects different people differently.

I started before the treatments.  I drank gallons of water, walked almost
100 miles in those 7 weeks, and slept an extra hour each night.  I ended up
with less diarrhea, less burning during urination, and less fatigue than
others that have reported here.  Indeed, my side effects were minor IMHO.

My report on impotence would be jaded by the inactivity thereof in my home,
but I think it adversely effected my sex life too for a short while and to a
slightly greater extent.

I am two thirds of the way through my salvage radiation treatment.  I
underwent a LRP almost 4 years ago.  My lowest post-op PSA was 0.06 but it
hovered around 0.2 for quite a long time then rose to 0.35 at which point we
decided it was time to take this step.

Thirty-six treatments in all, 5 days a week.

Side effects - nothing serious yet.  Bowel gets a little sensitive and I
suppose I am a little more tired.  I'm sure the last couple of weeks will be
a little tougher.  At worst now it feels like a mild hangover.  No worse
than that.  My treatments are first thing in the morning and I just go to
work from there.

Treatments themselves are nothing at all.  No discomfort or feeling of any
sort.  Takes about 5 - 10 minutes a day to get you lined up right and for
the machine to do it's thing.

No incontinence.  A few crumbs of Viagra still works reliably (I had one
nerve spared during surgery).

The treatments are administered by radiation therapists but I also meet with
the radiation oncologist weekly.  I'll ask him about the rate at which the
PSA should drop once treatments end.

...

You didn't say what the first treatment was.  I'm guessing that it
was a radical prostectomy and somehow, they didn't get it all.  

My rad-doc suggested that many "failures" of both surgery and rad,
roughly 10% or so, are due to extra-capsule microscopic
extensions. Not exactly metastacized but just sort-a, out there.  

That was why he recommended the 1, 2, 3 punch, Hormones, IMRT,
followed by seeds for me.  

Rad is slow.  The science is that the radiation, photons or
whatever, blasts holes in the cancer's DNA.  The cancer and the
regular prostate cells, and whatever else is nearby, survives the
radiation but is rendered incapable of reproduction.

What happens is that over the lifecycle of the cells, they run out
time and eventually die.  

This is a real problem for cells that reproduce on a short cycle.
That's cancer mostly but also the cells that line the urethra,
colon, and so on.

After rad, we gotta take it easy, give those cells time to heal and
recover.  

It also takes time for the cancer to die off.

How long?  I have no idea but it will probably be a couple years
before the docs give you the thumbs up.

Probably.  My rad-doc is relatively conservative but he said most of
his patients are fully functional without resorting to Vitamin-V or
other assists.   A percentage do need some help, I believe he quoted
30%.  

Yeah, good luck to you.