Major Radiation Overdoses at Florida Cancer Center

In the typical fashion of releasing bad news when most people are not focusing on the news, on Friday, April 2 H. Lee Moffitt Cancer Center & Research Institute released information that 77 patients received 50% higher radiation doses than prescribed. Whoa!

This is what we would call a major misadministration and the one thing that every Radiation Oncology professional fears. Boy, I can imagine the puckering sounds resonating in the executive and legal offices of that center. I'd say it is probably safe to say that there will be a few lawsuits filed in this case.

The technique used for these misadministrations is referred to as Stereotactic Radiosurgery. Basically this is a procedure that allows us to give higher doses of radiation by utilizing stereotactic techniques that minimize radiation doses to surrounding healthy tissues while delivering a therapeutic dose to the defined tumor volume. This is usually done in 1 to 5 fractions (treatments) instead of the normal 33 fractions for conventional Radiation Therapy. There are varying stereotactic techniques of which some require a frame screwed into the skull while others just require a thermoplastic mask that is molded into the shape of the patients head along with some type of bite block inserted into the mouth.

In most cases where a misadministration occurs, it is limited to a few patients. But in this case, it affected 77 patients from May '04 until last month. Not all of these were cancer patients. 21 of the patients were treated for benign processes such as AVM (arteriovenous malformation) or Acoustic Neuroma. Unlike most brain cancer patients, these individuals are expected to continue to live long healthy lives after their procedures are completed.

It was stated in the article that 12 patients have already died but didn't show any side effects of the overdose before passing. I would guess that these were most likely metastatic patients who were probably some of the first patients treated. Usually when initiating high risk procedures like this, you select patients that are going to die regardless of the results of the procedure. I know that probably sounds morbid but, the number one rule in medicine is to cause no more harm to a patient's condition than already exists. And in something like this, you sure want to have all possible problems eliminated before you perform the procedure on a curative or benign condition patient.

What is really sad about this unfortunate incident is that the effects of these misadministrations will not be realized for months or years in these patients. Radiation has a latent effect which means injury will not appear until a later time.

How did this happen? Good question. A place like Moffitt has at least 2 Medical Physicists and one Medical Dosimetrist. Probably more than that. That being said, if this staff was experienced, one would think that they would have questioned the higher than normal monitor units for the doses given. Monitor units are a measurement unit that we use to give the radiation doses on a linear accelerator.

Scuttlebutt in the field is stating that during the commissioning process of the new equipment there was data was converted to an MS Excel file and the cells were not protected. One of unprotected cells was then accidentally changed without anyone's knowledge. All subsequent QA was based on this incorrect data resulting in the dose errors.

There was an incident similar to this that occurred in a Nashville hospital in the early 90's. In that case a Medical Physicist inadvertently inserted a calibration factor twice. Luckily, this mistake was corrected early but still not until several patients had received large overdoses. A physician I knew saw one of these patients for a consultation to review the damage and it was not pretty.

Thank God for the RPC (Radiological Physics Center) in Houston. They are the organization that discovered this most recent error. This is an organization that tests Radiation Oncology facilities to assure that when they state they are giving a certain radiation dose they are indeed giving that dose. At major sites that perform clinical research protocols, they visit ever so often to test your equipment and check your QA. Our center participates in this program for the reasons mentioned above.

In the end, this will end up an expensive mistake that will cost the hospital lots of money, probably some people their jobs but most of all cost many patients their well being. One can only hope that the physicians were kind and caring physicians. Studies have shown that patients are least apt to sue if they fill that physician is caring and just made an honest mistake.