(ABC News) -- A Colorado woman died after injecting the supplement cesium chloride into her breast as an alternative treatment for breast cancer, according to a new case study published in The Journal of Alternative and Complementary Medicine.
The 61-year-old woman, whose name was not released for privacy reasons, had been taking cesium tablets and a handful of other vitamin supplements for more than a year, according to Dr. Daniel Sessions, the medical toxicologist who treated the woman at the Rocky Mountain Poison and Drug Center in Denver.
Cesium chloride is the salt form of the element cesium. It's often used in radioactive materials and sometimes used in rodent studies to produce the abnormal cardiac rhythms that scientists study to learn about heart function. It's sold as a dietary supplement in pill form and readily available at health food stores.
Cesium has been offered up as an alternative cure for cancer as far back as the 1920s, according to American Cancer Society research. Proponents of "high pH therapy" claim the pH inside of tumor cells is usually very low, or acidic, compared to normal cells, and that cesium chloride supplements raise the pH level of tumor cells to a normal level, which slows the cancer's growth.
But there is no scientific evidence that cesium is effective for fighting breast cancer and no clinical trials have looked into its effectiveness, according to the American Cancer Society. And long-term cesium use in animal studies caused serious blood and neuromuscular side effects and even death.
Sessions said the woman was following the advice of a nutritionist and that both she and her husband also worked for a supplement company. He said that the woman's doctor found a lump in her breast about a year before she died but she refused a biopsy even though she was told it was most likely cancer.
The night before she was rushed to the emergency room in 2011, her husband helped her crush up some cesium tablets, mix them with liquid and inject it into the mass, Sessions said.
"This was the first time she had taken an injection but not long after, she started to feel sick," Sessions told ABC News. "After a few hours, she went into cardiac arrest in front of her family and was rushed to the hospital."
By the time Sessions and the rest of the medical team examined her, the woman was in a vegetative state. She never regained consciousness and died 10 days later.
Sessions said several factors were the cause of the woman's death. For one, she had abnormally high levels of cesium in her blood. She also had advanced breast cancer that had spread into her lymph nodes. And her heart malfunction is a well-documented symptom of cesium injections, he added.
"These are known, common side effects of taking cesium," he said of the woman's abnormal heart rhythm, seizures and loss of consciousness.
Sessions stressed how dangerous it is to take unproven, unregulated supplements to treat a serious health condition like breast cancer. The woman's death should be a cautionary tale for anyone else considering the same sort of treatment, he said.
If you plan on using an alternative cancer therapy, run it by your physician or call the poison control center and get more information about what you're taking," he said. "You have to know what supplements you're putting in your body."
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