NEJM Published A Third Correction To A Lung Cancer Study. The New England Journal of Medicine just published an unbelievable third correction to a controversial medical study on the advisability of lung cancer screening. Although the study has long been in question over its ties to the tobacco industry, this third correction only serves to further weaken the study’s findings.
In March we reported that in late 2006, Dr. Claudia Henschke of Weill Cornell Medical College released a study revealing that the majority—80 percent—of lung cancer deaths could be prevented through widespread use of CT scans. The study was published in The New England Journal of Medicine and indicated—in small print at the end of the piece—that the work was financed, in part, by the Foundation for Lung Cancer: Early Detection, Prevention & Treatment. A tax record review later revealed the foundation was almost entirely underwritten by $3.6 million in grants from the parent company of the Liggett Group—the Vector Group—maker of Liggett Select, Eve, Grand Prix, Quest, and Pyramid cigarette brands. From 2000 to 2003, the foundation received four grants from Vector.
Regular cancer screening is not common for lung cancer as it is in colon and breast cancers, despite that lung cancer is the largest cancer killer. Also, no study thus far has clearly proven lung cancer screening would reduce its death rate. Henschke’s 2006 study is the leading study to favor such screening. In that study, researchers scanned over 30,000 patients with a computed tomography machine and found first-stage cancers in 407 and, among those in whom cancer was detected, the majority underwent surgery to remove their cancers within a month, experiencing a 92 percent chance of surviving for 10 years. Allegedly.
Study Lacked A Comparison Group
The study lacked a comparison group, so interpretation was difficult. Also difficult was determining if those patients would have lived for 10 years without screening and surgery. And, based on other patients’ records, estimates have ranged widely—between 50 or 70 percent. Meanwhile, the study noted that in a group of eight patients found to have first-stage cancer but who did not receive surgery, all eight died within five years. Henschke has quoted the eight-patient figure in several follow-up articles discussing and defending the study.
The data was wrong. Henschke wrote in a letter that the Journal just released on its Web site that not eight, but three patients, were in the group, rendering the comparison significantly less reliable. Henschke’s also disclosed that one of the hospitals participating in the study did not follow the study’s protocol, causing the need for a variety of other data adjustments. The letter is the third correction the Journal has published to the study. Previously, Henschke and a colleague acknowledged they received undisclosed royalties related to screening machines and that the study was partly funded by tobacco giant Vector Group Ltd.
In March, Dr. Jeffrey M. Drazen, the Journal’s editor-in-chief expressed surprise at the study’s funding, “In the seven years that I’ve been here, we have never knowingly published anything supported by” a cigarette maker. Prominent cancer researchers and journal editors were also stunned to learn of the study’s tobacco link.