Oversight of Dangerous High-Dose Medical Radiation
A rare and revealing sentence in the February 10 New York Times reported what Nukewatch and other watchdog groups like Public Citizen have warned about for years: "Patients today receive far more radiation than ever before. The average lifetime dose of diagnostic radiation—excluding therapeutic radiation—has increased sevenfold since 1980, prompting widespread concerns that certain procedures are overused and that they needlessly expose patients to an increased risk of cancer. Children and women are particularly vulnerable." The warning was part of last winter’s announcement by the U.S. Food and Drug Administration that it would expand its lax and often unenforced regulation of medical radiation procedures that expose patients to high doses, in particular CT scans which can dose individuals with the equivalent of 400 chest X-rays.
The FDA’s oversight decision came on the heels of several critical studies and after hundreds of radiation overdoses caused by poorly calibrated (and mostly unmonitored) radiation machinery and by undertrained operators. The FDA is investigating why over 300 patients at 4 different hospitals were exposed to as much as 8 times as much radiation as intended by powerful CT machines used to detect strokes. The largest overdoses were administered in 2009 at Cedars-Sinai Medical Center in Los Angeles and at two other California hospitals. (The gross radiation exposures were only discovered after some patients lost their hair.) In an April 8 announcement, the FDA admitted that it had reviewed over 1,000 reports of radiation exposure errors filed over the last 10 years.
California’s overdoses were echoed by similar events in Missouri at the CoxHealth hospital in Springfield, and at the Moffitt Cancer Center in Tampa, Florida. At CoxHealth, over a 5-year period, 76 patients, most with brain cancer, were "overradiated" according to a February 25 report. At Moffitt, 77 brain cancer subjects received 50 percent more radiation than what was ordered between 2004 and 2005.
As the Times’s January exposé said, these overdoses were caused by new equipment that was miscalibrated and by "hospitals that violate safety rules, injure patients, and fail to report mistakes." CoxHealth president and CEO Robert Bezanson made public a letter he sent in February to the FDA warning that its recent decision to toughen oversight of diagnostic radiation was too limited: "The initiative should be broadened to include regulation of medical radiation therapy as well."
In April, the FDA seemed to take stock of the advice and announced it would work to prevent overdoses in radiation therapy and, in particular, halt the use of "streamlined approval" for new machines. Some skepticism about the announcement was voiced by Dr. Howard Amols at Memorial Sloan-Kettering Cancer Center in New York, who told the Times, "It’s not clear that FDA has the expertise to police this," considering serious nationwide shortcomings in staffing, competency, and hospital quality control programs.
The new emphasis on oversight has also been clouded by allegations of FDA retaliation against one of its scientists, Dr. Julian Nicholas, who says he was fired after he recommended against the approval of CT scanners for routine colon cancer screening. "Nicholas said he objected to exposing otherwise healthy patients to the cancer risks of radiation," the AP reported.
A 2009 study in the New England Journal of Medicine said 4 million people in the U.S. get dangerously high doses of radiation from CT and PET scanners and that 400,000 get very high doses. The over-use of medical scans are "unnecessary, wasteful and dangerous" and may be "causing tens of thousands of additional cancers," according to Dr. Atul Gawande, a surgeon at the Dana-Farber Cancer Institute, and Dr. Rita Redberg, a cardiologist at UC San Francisco.
The FDA says it hopes to reduce unnecessary radiation exposures from three principal medical imaging systems: CT scans, which create three-dimensional images; radioactive ingestion studies, in which patients are given radioactive substances that doctors watch move through the body; and fluoroscopies, in which a radiation-emitting device projects an internal image on a monitor. "These types of imaging exams expose patients to ionizing radiation, a type of radiation that can increase a person’s lifetime cancer risk," the FDA now warns. A 2007 study published in the New England Journal of Medicine reported that as many as 2 percent of all future cancers in the U.S. may be due to radiation from CT scans given now.
The group Public Citizen and others have repeatedly charged that the FDA allows manufacturers to sell the imaging machines "without first having to prove their safety." Now, the FDA says it might require manufacturers of scanners and fluoroscopic machines to build in new safeguards and provide better training to operators. FDA-proposed improvements include: that the equipment display, record, and report calibration settings and radiation doses; that an alert be issued when radiation exposures exceed the optimal dose; and that machines be required to capture and transmit radiation dose information to a patient’s electronic medical record and to national dose registries.
Dr. James Thrall, professor of radiology at Harvard Medical School and chair of the American College of Radiology, told the Times that a major hazard with most scanners is that, "There is nothing on the machine that tells the technologist that they’ve dialed in a badly incorrect radiation exposure."
John LaForge is on the Nukewatch staff and edits its quarterly newsletter.