SPRINGFIELD — Half of the patients who received a specific cancer treatment in the last five years from CoxHealth were exposed to dangerous levels of radiation, the hospital confirmed Wednesday.
Hospital officials said they can't yet determine if the overdoses caused or contributed to any deaths, but they are examining records to determine if they did.
"It is totally unacceptable to us that an error like this ever occurred," said John Duff, senior vice president of hospital operations for CoxHealth. "We intend that no such error will occur ever again in the future."
Of the 152 patients who received treatment from a specific piece of technology, 76 were given between 20 and 70 percent more than their prescribed dose of radiation. The others received what is considered safe, or "therapeutic," levels of radiation — which could be as much as 10 percent more than what was prescribed.
Of the entire group of patients treated with the improperly programmed BrainLAB attachment, 90 died, which is 59 percent. In the group that received more than 10 percent too much radiation, 48 patients — or 63 percent — died.
At a press conference, officials were asked if the rate of death in the overly radiated group was higher than what might be expected.
"In many cases, the tumors that these patients had were very serious, and many of these patients had a poor prognosis when they began their treatments," Duff said. "A review of patient records is ongoing and not yet complete, so it would be premature to say the overexposure had any impact on the current medical condition or, of those patients who are deceased, if it was a contributing factor in those deaths."
The error was the result of a physicist — a board-certified technician — using the wrong tool to calibrate the BrainLAB attachment on the radiation machine. The error went undetected for five years, when in September 2009 a newly hired second physicist questioned the calibrating tools used by the chief physicist. All BrainLAB treatments were suspended at that time.
An internal and subsequent outside audit confirmed that the machine was calibrated correctly for all target areas except for those 1.1 centimeters or smaller. The hospital resumed the treatment for larger tumors in November.
After further data showed that the variances in the radiation levels were off by high percentages, the entire program was suspended in January 2010. Duff said the program will remain suspended indefinitely.
CoxHealth received the final results after an analysis of all 152 patients' radiation levels Feb. 16. Duff said the hospital has been contacting patients since then.
The physicist who calibrated the machine no longer works at CoxHealth, but Duff declined to say whether the individual was fired or left voluntarily. He said hospital policy has changed to ensure more safeguards and more trained staff monitoring radiation technology.
Duff said staff who periodically checked the machine used the same tool the original physicist did, which showed there were no problems. He said hospital staff had no reason to think anything was wrong since no patients exhibited any alarming symptoms.
The BrainLAB stereotactic radiation therapy system is an attachment and corresponding software used on a device that emits radiation to treat tumors. The program is designed to target the tumor and avoid the tissue around the area, said John Clouse, the medical director of radiation and oncology at the Hulston Cancer Center.
Clouse said the damage caused by radiation can look like a tumor, which will make it difficult to determine whether the radiation was a cause of death.
The health care industry has come under fire, along with governmental groups that advocates say should be regulating them, for allowing too many radiation technology machines and corresponding software to go unregulated.
Duff said the hospital has reported to the Joint Committee — the hospital's accrediting association — and the Department of Health and Senior Services. He said the hospital intends to work with the Food and Drug Administration on measures to prevent future mistakes.
"There are no federal agencies or state agencies that require reporting radiation overexposure," he said. "Some states do have such agencies — Missouri does not."
Clouse said surviving patients will be monitored for possible damage, as it can take years for symptoms to emerge. CoxHealth will absorb the related costs.
Cox officials say they've notified patients or their families in about 70 of the 76 overdose cases.