Study identifies causes of bone loss in breast cancer survivors

Nov 19, 2008

Osteoporosis is a growing concern among breast cancer survivors and their doctors, because certain cancer drugs can cause bone loss.

But a new study has found that cancer drugs aren't the only culprits. Among 64 breast cancer patients referred to a bone health clinic, 78 percent had at least one other cause of bone loss, including vitamin D deficiency, excessive calcium excretion in urine and an overactive parathyroid gland.

"Doctors evaluating breast cancer patients for possible bone loss should look further than cancer drugs," said Dr. Pauline Camacho, lead author of the study in the Journal of Clinical Oncology. Camacho is an associate professor in the department of medicine, division of endocrinology and metabolism, Loyola University Chicago Stritch School of Medicine.

A co-author of the study, Dr. Kathy Albain, said breast cancer survivors "are just like the normal population as they age in that bone loss can be due to many treatable causes." Albain is a professor in the Department of Medicine, division of hematology/oncology at Stritch.

Previous studies have found that chemotherapy drugs can cause bone loss. Studies also have found that a class of breast cancer drugs called aromatase inhibitors can decrease bone mineral density and increase the risk of fractures in postmenopausal women. Aromatase inhibitors decrease the body's production of estrogen. While estrogen feeds cancer, it also protects against osteoporosis. Aromatase inhibitors include letrozole (trade name, Femara), anastrazole (Arimidex) and exemestane (Aromasin).

Researchers reviewed charts of 238 consecutive postmenopausal patients who had osteoporosis or osteopenia and were referred to the Loyola's Osteoporosis and Metabolic Bone Disease Center from 2000 to 2006. (Osteopenia is lower than normal bone mineral density, but not low enough to be classified as osteoporosis.) The patients included 64 women with breast cancer referred from Loyola's Cardinal Bernardin Cancer Center and 174 patients without breast cancer referred from primary care physicians.

Thirty eight percent of the breast cancer patients had vitamin D deficiency, compared with 51 percent of the non breast cancer patients. Another cause of osteoporosis, excessive calcium excretion in urine, was found in 16 percent of cancer patients and 8 percent of noncancer patients. And in 5 percent of patients, the parathyroid gland was overactive, producing a hormone that causes bone to lose calcium.

Vitamin D deficiency can be treated with prescription doses of vitamin D supplements. Excessive calcium excretion can be treated with a "water pill" that's also used to treat high blood pressure, Camacho said. There are various treatments for parathyroid gland disorder, depending on its cause.

In certain breast cancer patients, bone loss from cancer drugs can be treated with osteoporosis drugs such as alendronate sodium (Fosamax) and ibandronate sodium (Boniva), Camacho said.

Albain refers all her breast cancer patients for a comprehensive bone health evaluation when osteopenia or osteoporosis is discovered. "Just prescribing a medication for osteoporosis may not be enough for many of our patients," Albain said. "They deserve a thorough workup."

Patient Rosaleen O'Connor, 71, of Elmhurst, Il., learned she had osteoporosis while being treated by Albain for breast cancer. Albain referred O'Connor to Camacho, who prescribed calcium supplements, prescription vitamin D and the osteoporosis drug Boniva. Three years after O'Connor was diagnosed, her Stage 3 cancer is in remission, and she has suffered no bone fractures.

Source: Loyola University Health System

Explore further: Chronic inflammation linked to 'high-grade' prostate cancer

add to favorites email to friend print save as pdf

Related Stories

A microchip for metastasis

Feb 06, 2014

Nearly 70 percent of patients with advanced breast cancer experience skeletal metastasis, in which cancer cells migrate from a primary tumor into bone—a painful development that can cause fractures and ...

3,200-year-old skeleton found with cancer

Mar 17, 2014

Archaeologists have found the 3,200-year-old skeleton of a man with a spreading form of cancer, the oldest example so far of a disease often associated with modern lifestyles, scientists said Monday.

Tracking breast cancer cells on the move

Jun 14, 2012

Breast cancer cells frequently move from their primary site and invade bone, decreasing a patient's chance of survival. This process of metastasis is complex, and factors both within the breast cancer cells and within the ...

New sensors streamline detection of estrogenic compounds

Aug 25, 2011

Researchers have engineered new sensors that fluoresce in the presence of compounds that interact with estrogen receptors in human cells. The sensors detect natural or human-made substances that alter estrogenic signaling ...

Recommended for you

Chronic inflammation linked to 'high-grade' prostate cancer

1 hour ago

Men who show signs of chronic inflammation in non-cancerous prostate tissue may have nearly twice the risk of actually having prostate cancer than those with no inflammation, according to results of a new study led by researchers ...

Unraveling the 'black ribbon' around lung cancer

14 hours ago

It's not uncommon these days to find a colored ribbon representing a disease. A pink ribbon is well known to signify breast cancer. But what color ribbon does one think of with lung cancer?

User comments : 0

More news stories

Chronic inflammation linked to 'high-grade' prostate cancer

Men who show signs of chronic inflammation in non-cancerous prostate tissue may have nearly twice the risk of actually having prostate cancer than those with no inflammation, according to results of a new study led by researchers ...

Turning off depression in the brain

Scientists have traced vulnerability to depression-like behaviors in mice to out-of-balance electrical activity inside neurons of the brain's reward circuit and experimentally reversed it – but there's ...

Better thermal-imaging lens from waste sulfur

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...