Prostate Cancer and Bone Health

Bone health may be affected by prostate cancer and its treatment. It is important to understand what is going on inside your bones, why men with prostate cancer need to be aware of what can happen to their bones, and what you and your doctor can do to make sure that you maintain bone health.

Two conditions that can arise and impact your health are:

• Treatment-Induced Bone Loss which can be caused by medications that lower male hormones
• Bone Metastases which are a result of advancing prostate cancer when the disease spreads to the bones

About Your Bones

Healthy bones allow you to be more active, which in turn can make your bones healthier.

Bones perform several functions.  They provide the body’s framework and act as the attachment point for muscles, allow movement, protect your organs, store and release minerals needed for bodily functions, and produce blood

Bone is living tissue. It contains cells called osteoblasts that create bone, and cells called osteoclasts that break down the bone and release the minerals they contain. After age 30, bone breakdown occurs at a slightly faster pace than bone production. Though this is a very slow process, the deficit builds over time; hence, our bones become less dense, and therefore weaker, as we grow older.

What You Can Do to Maintain Healthy Bones

• Eat a healthy diet: Men over age 50 should get at least 1200 mg of calcium every day. Green vegetables such as broccoli and spinach, defatted soy products such as soymilk, tofu and soy protein powder are good sources of calcium.
• Take a calcium supplement: The best source of calcium is your diet but you may need to speak with your doctor or dietician to consider taking a calcium supplement to attain your daily calcium requirement.
• Get your vitamin D: Your body needs vitamin D in order to absorb calcium. Recommended daily dose is 400 IU. Some people have low vitamin D levels and will require additional supplements. You should ask your doctor about checking your vitamin D levels to determine if you need additional vitamin D.
• Do not smoke or drink alcohol: Smoking and excess alcohol weakens your bones. If you do drink alcohol, limit the amount to one to two drinks per day.
• Exercise: Try to do some type of weight-bearing exercise for 30 minutes a day, four days a week. (Weight-bearing describes any activity you do on your feet that works your bones and muscles against gravity. These exercises include walking, low impact aerobics and stair climbing.) It is important, however, to avoid the kind of exercise that puts sudden or excessive strain on the bones. Ask you health care provider about the type of exercise that is best for you.

Prostate Cancer and Osteoporosis

Osteoporosis may occur in men with prostate cancer due to decreased testosterone levels resulting from their treatment.

Osteoporosis can make bones more prone to fracture. The bones most likely affected include the bones of the hip, wrist, and spine.

There are no warning signs of osteoporosis, however, it is manageable and may be preventable.

Diagnosing Osteoporosis

To diagnosis osteoporosis, your doctor should conduct a complete medical exam and review your medical and family history. It is important to know if your parents or siblings have a history of osteoporosis or fractures

Your doctor may also order a bone mineral density (BMD) test. This is an x-ray test that measures bone density. Low bone density is associated with lower bone strength and an increased risk for future fractures.

A BMD may be ordered by your doctor prior to hormonal therapy if you are at high risk for low bone density. During hormone therapy your bone mineral density will continue to be monitored. Keep a copy of the BMD report in pocket of the back cover.

Treating Osteoporosis

Lifestyle factors make an important difference in the treatment of osteoporosis. Avoiding excessive alcohol, stopping any use of tobacco products, and getting regular exercise are important.

In addition, there are medications available that help maintain bone tissue. Most are “antiresorptives”, which means that they work by slowing down or stopping the action of the osteoclasts, the cells that break down bone tissue. The bisphosphonates are medications that slow bone loss and, in some cases, increase bone mass. f your tests determine that you have a low BMD; you may be prescribed a bisphosphonate to help improve your bone density. Fosamax® (alendronate) and Actonel® (risedronate) are two bisphosphonates that are approved in the U.S. for bone loss in men. They are taken by mouth, once a day or once a week

If you are someone who does not like to take medications daily or weekly, or who has swallowing problems or reflux disease of the esophagus, there is an intravenous bisphosphonate called Zometa® (zoledronic acid) that can be given once a year to treat bone loss. While taking Zometa®, you should also be given calcium and vitamin D.

Questions to Ask Your Doctor

• Am I at an increased risk for bone loss or osteoporosis?
• How does my prostate cancer and its treatment affect my bones?
• Am I currently taking any medication, or have I had any treatment in the past, that increases my risk for bone loss?
• Is it safe for me to exercise? If so, what exercise is best for me?
• Am I at an increased risk for bone loss or osteoporosis?
• Are there any other steps I can take to slow bone loss or increase my bone density?

Bone Metastases

Prostate cancer behaves differently in each individual. In many men, prostate cancer never spreads to any other site. If the cancer does spread, it tends to spread to the bones. Prostate cancer that spreads to the bones is still prostate cancer, not bone cancer.

Bone metastases may result in areas of weak, unstable bone that could cause debilitating pain and fractures. Finding bone involvement as soon as it occurs is important. The section below describes some common symptoms of bone metastases.

Symptoms of Bone Metastases

• Pain is the most common symptom of bone metastases, yet metastases often occur without pain or other symptoms.
• Arthritic pain can be confused with pain from bone metastases. To help distinguish between the two types of bone pain, it is important to know that the pain associated with bone metastases usually does not occur in the joints and it is a lingering pain; it doesn’t just go away by itself in a few days.
• If you are having any type of bone pain, you should discuss this with your doctor.

Diagnosing Bone Metastases

Tests used to diagnose bone metastases include:

• Radionuclide Bone Scans
• X-rays
• MRI scans
• CT scans

The tests most often used are a bone scan followed by an MRI, if needed.

Treating Bone Metastases

• Hormone therapy (androgen deprivation or ADT) is an important treatment for bone metastases. It is based on depriving the cancer cells of the growth stimulation that hormones provide.

• IV bisphosphonate therapy is an important option for the treatment of bone complications of prostate cancer. Unlike other treatments that focus on the cancer, IV bisphosphonates act on the bones directly and do not attack the cancer cells. This medication slows the bone-destroying activity that occurs with bone metastases by working directly against the cells (osteoclasts) that cause the abnormal bone destruction.
• Radiation therapy is the use of high-energy rays to kill cancer cells. It is effective in reducing bone pain and preventing fractures and is especially useful if just a single area requires treatment.

• Surgery may be used to reinforce a bone that is at risk for breaking or to repair a bone that has already broken.
• Chemotherapy is directed against the cancer itself and involves the use of anticancer drugs, which are injected into a vein or taken by mouth. These drugs enter the bloodstream and travel to the metastases to kill the cancer cells.

Summary

• You can make a difference in managing your bone health.
• Not all symptoms are from prostate cancer.
• Maintaining your bone health will help maintain your quality of life.
• Do not let symptoms scare you. See them as a signal to get more information and take action. If you have symptoms that concern you, tell your health care provider right away. The sooner your symptoms are evaluated, the more treatment options will be available to you, and the more effective those treatments will be.
• You are the expert on you. Know your body...and trust yourself.