According to an article in the New York Times, investigators running a trial to determine whether CT screening for lung cancer is effective in reducing mortality rates cannot locate 90% of the informed consent forms, casting doubt on whether consent was appropriately obtained for tens of thousands of patients who were subjected to significant quantities of radiation.
According to the article: "In medical experiments on human beings, every patient must sign an “informed consent” form acknowledging the risks, and researchers are required to keep track of those statements. But the doctors who conducted a controversial, widely publicized lung cancer study involving more than 50,000 patients at numerous hospitals were unable to locate 90 percent of the consent forms, according to a confidential review provided to The New York Times. The finding casts further doubt on a clinical trial that made headlines in 2006 when it concluded that fully 80 percent of lung cancer deaths could be prevented through wide use of CT scans."
A scientific reviewer who was called in to assess the situation is quoted in the article as stating that he has no confidence that informed consent was actually obtained for tens of thousands of patients: "One reviewer, Dr. David P. Carbone, a professor of medicine and cancer biology at Vanderbilt, said in an interview that he and the other reviewers never found out 'whether these consents were obtained and lost or whether they weren’t obtained at all.'"
One medical journal that published work from the research - entitled the International Early Lung Cancer Action Program (ELCAP) - stated that it would be forced to retract that article if the consent forms cannot be located: "Dr. Bruce A. Chabner, director of clinical research at Massachusetts General Hospital Cancer Center and editor in chief of The Oncologist journal, said he would ask Weill Cornell for an explanation of the problems outlined in the 2008 scientific review, as well as a follow-up to the report. His journal has published research by Dr. Henschke, and 'if we find there was no informed consent for those patients, the paper would have to retracted,' he said."
The Rest of the Story
This appears to be a very serious violation of responsible research conduct. It is particularly troubling because this is not a minimal risk study. Subjects in the ELCAP trial are subjected to significant doses of radiation, which itself presents a small cancer risk. If subjects were entered into the trial without informed consent, this would be a major ethical breach.
A single CT scan can expose a patient to the equivalent amount of radiation as up to 442 chest x-rays. Some researchers have estimated that radiation delivered by CT scans in one year will result in a total of 29,000 future cases of cancer. Thus, the risks to which patients were exposed in the ELCAP trial are not trivial and the failure to be able to document informed consent is a major problem.
Long-time readers of the Rest of the Story may recognize that this is not the first time this research has been the subject of a commentary. The institution where the bulk of the research was conducted - the Weill Cornell Medical College - was awarded my Pants On Fire Runner-Up Award in 2009 for falsely claiming that an apology was made for its investigators' failure to disclose a significant conflict of interest in their article on the role of low-dose CT scans in screening for lung cancer.
That financial interest: the principal investigator of the study receives royalties from General Electric on intellectual property she invented which involves the use of CT scanning for early diagnosis of lung cancer, intellectual property which was licensed to General Electric.
Thus, the investigator stands to gain financially if CT scanning is found to be effective in reducing cancer mortality. I wonder if this fact was disclosed to study participants. My personal view is that it would have been unethical not to inform patients of this financial conflict of interest.
Sadly, the rest of the story is that the researchers cannot even document that informed consent was obtained, much less that the financial conflict of interest was disclosed to potential study participants.