Tuesday, March 22, 2011

Riddled With Metal by Mistake in a Study

March 21, 2011

Riddled With Metal by Mistake in a Study

Women participating in a study of patients with breast cancer have been inadvertently left with hundreds of tiny particles of the heavy metal tungsten in their breast tissue and chest muscles. The particles came from a device used during surgery. The device has since been recalled.
It is not known if the metal is dangerous to health because relatively little research has been done on its long-term effects in the body. But it shows up on mammograms, and may make them difficult to read, an especially troubling effect for women who have already had breast cancer and worry about recurrences. (The particles resemble calcium deposits, which can indicate cancer.)
About 30 women have been affected, according to the manufacturer of the device that caused the problem, the Axxent FlexiShield Mini. The women are in a quandary. At least one, fearing that the tungsten could cause cancer or another illness, is trying to decide whether to get rid of the particles by having her breast and its underlying tissue removed in a radical and disfiguring operation.
Twenty-seven of the cases occurred at Hoag Memorial Hospital Presbyterian in Newport Beach, Calif. Eleven of those women have had mammograms, and all 11 showed tungsten. Hospital officials declined interviews, but issued a statement acknowledging that the problem had occurred.
Two other women were treated in a study at Karmanos-Crittenton Cancer Center in Rochester Hills, Mich. A hospital spokeswoman said that both patients had been informed of the recall and the potential problem but had not returned to the hospital.
The episode casts doubt on the safeguards for people who participate in medical research and on the Food and Drug Administration’s ability to protect the public from flawed medical devices.
The Axxent FlexiShield Mini had been cleared by the agency in June 2009 in an abbreviated process used for devices that are considered equivalent to products already on the market. That process, known as 510(k), takes less time than the procedure used to approve a new device, and it generally does not require tests on humans. The FlexiShield Mini equipment was recalled last month. Neither its manufacturer nor the F.D.A. could explain what went wrong with the device.
Karen Riley, a spokeswoman for the agency, said it was just beginning its review of the device and the recall. So far, she said, F.D.A. toxicologists had found no evidence that the tungsten was toxic or that patients were harmed.
Ms. Riley said the 510(k) process was used to avoid “reinventing the wheel” for products that were essentially the same as others that had already passed muster with the agency.
The women who were exposed to the tungsten were taking part in a study of a radiation technique that some doctors predicted would be a big advance in the treatment of breast cancer. Unlike the usual five to seven weeks of daily radiation sessions, the newer method delivers the entire course of treatment in one dose while the woman is still in the operating room after undergoing a lumpectomy for breast cancer.
But in the study, a device that was temporarily placed in the women’s incisions during the radiation treatment was apparently flawed, and riddled their breasts with tungsten. The Axxent Flexishield Mini, a $100 disk made of tungsten and silicone, was used to shield healthy tissue from the radiation.
The first patient to take part in the study at Hoag said the events had shattered her faith in the vigilance of the drug agency, the hospital and her surgeon, who she said enthusiastically talked her into participating, emphasizing how convenient it would be to finish radiation treatment before she even woke from surgery.
“I do work, so it was appealing,” said the woman, a 57-year-old psychologist with a busy practice who did not want her name used for privacy reasons.
The purpose of the study was not to test the new radiation treatment itself, but rather to determine whether imaging studies could correctly predict which women would be candidates for it. The device’s manufacturer did not pay for the study.
It never occurred to the first patient that the equipment might be faulty, she said, because she knew that it had been approved by the F.D.A. She also trusted the doctor and hospital to ensure that the study was safe.
“I had this illusion, like most people do, that the F.D.A. wouldn’t allow this to happen,” she said. “I definitely feel like a lab rat now.”
The manufacturer, Xoft, which was bought in December by iCad, intended the shield to be used with its portable radiation device, the Axxent Electronic Brachytherapy System.
The president of iCad, Ken Ferry, said his company bought Xoft because the idea of giving radiation treatment during surgery seemed so promising. A study published last summer showed good results from a different radiation machine using the same technique. Mr. Ferry said he thought the procedure might eventually be used to treat half of the 270,000 women a year in the United States who develop breast cancer.
“We think the growth of the procedure will be dramatic over the next three years,” Mr. Ferry said. “That’s what really drove us to acquire the company.”
But iCad also acquired the tungsten problem, which became apparent only a week or two after the deal was closed.
“Dumb luck, if you want to use that word, is what it feels like to iCad that we ran into it,” Mr. Ferry said. But, he added, “it doesn’t diminish our enthusiasm.”
The psychologist is suing Hoag and the manufacturer.
She first learned that something was wrong in December, when she had a routine follow-up mammogram six months after her lumpectomy and radiation.
The image showed hundreds of tiny spots scattered inside her breast and along the muscle at the back of her chest wall. Doctors did not know what the spots were, but her radiologist said some resembled the calcifications that can indicate cancer. “I was terrified,” she said. “It looked like it was snowing inside my breast.”
A biopsy found the tungsten.
“I went to my oncologist,” she said. “He just was beside himself. He just said: ‘You’ve got to get this out of you. It’s toxic. You can’t have this in your system.’ ”
He urged her to have a mastectomy and recommended a surgeon, who told her that to remove the tungsten, he would have to remove her entire breast and some of the chest muscles.
“I would have a dent in my side,” she said. “He said he didn’t really want to move ahead until there was more information because it would be so disfiguring. That made me physically ill. I’d kind of gotten myself used to the idea of having a mastectomy, but not being disfigured.”
ICad has offered to pay for toxicology consultations for the exposed women, along with blood and urine tests to measure tungsten. The company has also said it will consider paying for mastectomies, and it commissioned a report to examine the scientific data on tungsten. The report said its toxicity appeared low, but that long-term studies were lacking.
Dr. Steven Markowitz, a physician at Queens College in New York who specializes in occupational and environmental medicine, said there was not much information about the effects of pure tungsten like that used in the shields. Most research, he said, involves workplace exposure to tungsten compounds.
“Given this unorthodox route of exposure, it’s hard to say a whole lot about likely consequences,” Dr. Markowitz said.
The first patient in the Hoag study said she had consulted a toxicologist, who told her little was known about the long-term health effects of tungsten but said that she (the toxicologist) would probably not leave it in her own body. The patient said that she was leaning toward having the surgery. But, she added, “I would love to hear there’s evidence that there’s nothing to worry about.”

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