Federal investigators are scrutinizing a series of flawed brachytherapy implants at the Veterans Affairs (VA) hospital in Philadelphia as well as those at other VA hospitals. According to a June 21 report in the New York Times, over a span of more than six years, 92 of 116 brachytherapy treatments had botched dosing during the procedures.

The implant errors resulted from a system-wide failure, in which none of the safeguards that were supposed to protect veterans from poor medical care worked, the NY Times reported.

Most implants were performed by radiation oncologist, Gary Kao, MD, who has since stopped seeing patients and is now performing lab work for the University of Pennsylvania School of Medicine in Philadelphia. In 2003, in treating one patient with prostate cancer at the VA hospital in Philadelphia, Kao implanted 40 radioactive seeds in the patient's healthy bladder instead of the prostate. According to investigators, he rewrote his surgical plan to match the number of seeds in the prostate.

The patient underwent a second implant, which failed as well. This time, the dose was implanted in the patient's rectum. The NY Times reported that two years later, Kao rewrote another surgical plan after putting half the seeds in the wrong organ.

The Nuclear Regulatory Commission (NRC) said that the implant program lacked a "safety culture," and that Kao and other members of his team were not properly supervised or trained.

The NY Times reported that the implants in Philadelphia were reported to the nuclear commission. With no investigation, this meant that many patients were unaware for weeks, months and sometimes years that their cancer treatments were flawed.

The two incidents in Philadelphia have prompted the NRC staff to propose allowing revisions to surgical plans only before an implant is done, according to the NY Times. The Philadelphia prostate unit has been closed and has yet to reopen.  Additionally, the VA has also suspended the implants at hospitals in Jackson, Miss., and Cincinnati.