<http://www.prostatecancerfoundation.org/site/c.itIWK2OSG/b.47320/k.3A88/Managing
_Bone_Metastases_and_Pain.htm>

Managing Bone Metastases and Pain

Prostate cancer cells that spread to the bone are known as prostate cancer
bone metastases (not bone cancer). Once they settle in the bone, the
cancer cells begin to interfere with the normal health and strength of the
bones, often leading to bone pain, fracture, or other complications that
can significantly impair one’s health.

Early detection of bone metastases can help to determine the best
treatment strategy, and can help to ward off complications caused by the
metastases.

In addition, because men with prostate cancer bone metastases often
experience painful episodes, pain management and improving quality of life
is an important part of all treatment strategies for men with bone
metastases.

Treating Metastases

An important part of prostate cancer bone metastases management is
maintaining adequate calcium and vitamin D levels and exercising
regularly. Even though none of these are treatments for bone metastases,
they will all help to maintain strong bones and help to minimize bone loss
and osteoporosis, which can make treating bone metastases more
challenging.

Radiation Therapy Targeting Bone Metastases
Men who experience pain from a bone metastasis will often be treated with
radiation targeted directly to the metastasis. This will kill the prostate
cancer cells and relieve the pain. (Note that radiation therapy used to
treat bone metastases is completely unrelated to radiation therapy that
might have been used earlier in prostate cancer treatment.)

External beam radiation therapy uses x-rays to kill the cancer cells that
have settled in the bones. This type of treatment, sometimes referred to
as spot radiation, is mapped out and planned very precisely by the
radiation oncologist to ensure that the x-rays are targeting the
metastasis and are not causing damage to the surrounding bone and muscle
tissue.

Radiopharmaceuticals, or radioactive drugs, are injected into the body
through a vein and settle in the bone metastases, at which point they
release radiation to the local area and kill the cancer cells. The two
drugs used for this procedure, samarium (Quadramet) and strontium
(Metastron), are sometimes used in combination with chemotherapy.

Bone-Targeting Agents (Bisphosphonates)
Under normal circumstances, bone cells are destroyed and created at a
constant rate. Increasing the activity of osteoblasts, cells that form new
bone cells, ultimately results in an overgrowth of bone tissue; increasing
the activity of osteoclasts, cells that destroy bone cells, ultimately
results in porous, brittle bone tissue. In men with prostate cancer bone
metastases, both of these processes occur at faster than normal rates,
leading to both an overgrowth of bone tissue and weakened and brittle
bones. The combination of these two processes makes the bones unstable,
and therefore prone to fracture.

Bisphosphonates are drugs that are designed to help reset the balance in
the bone between bone growth and bone destruction. Zoledronic acid
(Zometa) is a bisphosphonate given intravenously that can delay the onset
of complications associated with prostate cancer bone metastases and
relieve pain. It is typically given once every three weeks as a 15-minute
infusion.

Other bisphosphonates are sometimes used in men with prostate cancer to
prevent or slow bone loss while taking hormone therapy. These drugs,
alendronate (Fosamax) and risedronate (Actonel), are given in pill form,
and are also used to counteract the bone loss of osteoporosis in
postmenopausal women or in women who are taking hormone therapy for breast
cancer.

Anticipating Complications

Treatment for prostate cancer bone metastases has three goals: to slow
disease progression, to relieve pain, and, perhaps most importantly, to
avoid the complications that stem from the weakened bone caused by the
metastases.

Bone that is weakened by metastases is more prone to fracture, and because
the metastases often grow around the lower back and upper legs, hip
fractures tend to be most common. Vigilant monitoring for fractures is
common; less commonly, surgery might be considered to stabilize bones at
risk. This procedure can improve the chances of not fracturing the bones,
and therefore help to stave off other complications down the road.

The most significant complication from bone metastases is spinal cord
compression. A weakening of a vertebra by a prostate cancer bone
metastasis can result in the bones of the spinal column collapsing one on
top of the other, compressing the spinal cord housed within the bones as
well as the nerves that run out from it.

Cord compression associated with metastatic prostate cancer can cause
severe nerve damage, and possibly paralysis, if not managed immediately.
Therefore, additional medications, such as steroids, might be used for men
at high risk for a spinal cord compression, and surgery to stabilize the
weakened bones might be considered. MRI scans can also be used to better
visualize the health of the spinal column and to detect early any problems
that might occur.

The symptoms of spinal cord compression are often similar to those seen
with many other medical problems. For example, because bone metastases
typically occur around the lower back and upper legs, compression of the
spinal cord at that point can cause back pain, leg pain or weakness, or
loss of bladder or bowel control. It is therefore important to recognize
and address any symptoms as soon as possible. The earlier new fractures or
a spinal cord compression is detected, the easier it is to treat.

Managing Pain

There are three general rules of pain management to always keep in mind.

1. Don’t try to be too tough or act "macho". Untreated pain takes a toll
on the body, forcing it to expend a lot of energy fighting it.

2. There might be a very simple solution to the pain. Some very simple and
easy to take medications might be enough to ease the pain.

3. Don’t worry about becoming addicted to pain medication. The most common
reason that doctors are afraid to prescribe strong pain medications and
that people are afraid to take them is fear of addiction. But that’s
mostly because people don’t understand the differences between addiction,
physical dependence, and tolerance.

Addiction is a psychological and behavioral syndrome in which there is
continual or increasing use of a drug despite negative physical,
psychological, or social consequences. Taking pain medications to feel
healthier and stronger would seem to be exactly the opposite of addictive
behavior.

Someone who is physically dependent upon a drug will not be able to cope
with its loss if it is stopped or if the dose is lowered too rapidly, and
symptoms of withdrawal will be seen. This is why doses of strong pain
medications are usually tapered, or gradually lowered, before stopping,
giving the body a chance to adjust to its loss.

After using a certain drug for a long period of time, the body will become
tolerant to it, to the point where the drug is no longer effective. Slowly
increasing the doses over time can help to avoid the onset of tolerance,
but that’s only a temporary measure, and you’ll likely have to switch to a
medication that works in a slightly different manner before you can find
relief.

Note that every pain medication, like all other medications, has its own
set of side effects. Constipation is the most common side effect of pain
medication use; other side effects can include nausea and vomiting,
sleepiness, and confusion. Knowing which side effects to expect can help
decide how best to deal with them.