Osteoporosis

Early menopause caused by cancer treatment may lead to osteoporosis, which is the condition of low bone mass and low bone density.  The thinning and weakening of bones caused by osteoporosis increases risk for fracture, especially the spine, wrist, and hip.  Stooped posture, weight loss, curving of the upper back, bone tenderness, or loss of 1-2 inches in height may be signs of osteoporosis.

 

What causes osteoporosis?

Post-menopausal estrogen loss can cause osteoporosis through a decrease in bone density.  Doctors should closely monitor patients who have risk factors for osteoporosis.  Some factors doctors need to watch are older age, family history of osteoporosis, smoking, low body weight, or a history of broken bones.  Breast cancer treatments that cause early menopause also increase risk of osteoporosis.  These treatments include some chemotherapy drugs, aromatase inhibitors, exemestate, letrozole, and surgical removal of ovaries.

 

Diagnosing Osteoporosis

A bone mineral density test is used to diagnose osteoporosis.  X-ray absorptiometry is a specialized low-dose x-ray technique, commonly referred to as a densitometry or a DEXA scan.  This technique is used in a bone mineral density test, which calculates density according to amount of radiation absorbed by the bone.  The testing is not painful and takes about 20-30 minutes.

 

Managing Osteoporosis

There are several things patients can do to maintain bone density and prevent osteoporosis.  Patients should ensure they are taking a sufficient amount of calcium and vitamin D.  Women with breast cancer need 1200 mg of calcium and 400-800 U of vitamin D per day, according to The American Society of Clinical Oncology (ASCO).  Avoiding smoking and regular weigh-bearing exercise may help as well.  Sunlight also aids the body in producing vitamin D.  Therefore, a few minutes in the sun everyday is suggested.

Medications are also available for prevention and treatment of osteoporosis.  Some of these drugs are alendronate sodium (Fosamax), risedronate (Actonel), ibandronate (Boniva) and zoledronic acid (Reclast).  Some of these medications are oral and can be taken daily or weekly, while other oral medications are only taken once per month.  Other medications are given as an injection once every 3 months. Some herbal supplements are marketed as preventing and treating osteoporosis, however there is not enough scientific research to be certain if this is true.  A physician should be consulted to find out what medications and what dosage schedule is best for each individual case.