It was only a couple of months ago that an article was published in the New England Journal of Medicine that claimed spiral CT scans for the early detection of lung cancer could significantly decrease deaths from this disease.
Now, a study reported in this week's Journal of the American Medical Association says that there is no evidence that screening for lung cancer with chest CT scans does anything to reduce deaths from lung cancer.
It does substantially increase the number of cancers detected and the number of surgeries performed, and exposes patients to significant risks for no net gain in survival.
Why all the confusion?
This past October, the New England Journal study indicated spiral CT scans were able to reduce deaths from lung cancer by finding nodules early. The survival rates of the patients with lung cancers found had been outstanding, according to the report --much better than had ever been seen previously.
Although hailed by many experts and advocates as the answer to our prayers to reduce the suffering and loss of life from this terrible disease, there were those at the time who felt the study did not provide sufficient evidence to recommend universally that current and former smokers rush out to get screened.
Left unanswered in that study was the possibility that the investigators were diagnosing lung cancers that never would have made a difference to the patient.
That's hard to believe, but it is a real concern.
This week's JAMA report adds some credibility to that argument, claiming that the evidence does not support the conclusion that lung cancer screening with CT scans reduces deaths from lung cancer.
In this study, the authors reported on the results of spiral CT scanning performed on over 3,200 patients screened at three academic medical centers, two in the United States and one in Italy.
They carefully examined the number of lung cancers diagnosed, the number of surgeries performed, the stage of the lung cancer at diagnosis and the rates of death from lung cancer in the patients who were screened. They then compared these rates with a set of data based on previous lung cancer trials to find out how many surgeries and deaths were observed compared to how many were expected.
The results were astonishing, to say the least.
In patients screened with spiral CT scans for the early detection of lung cancer, lung cancers were diagnosed three times more than would have been expected.
The number of surgeries to remove a lung cancer was 10 times (yes, 10 times) greater than what was expected.
Even with all of those lung cancers that were diagnosed and all those surgeries that were performed, there was no evidence that fewer people were diagnosed with advanced lung cancers than were expected.
Most important, the number of deaths from lung cancer was almost exactly the number of deaths predicted.
We have always thought of lung cancer as an almost uniformly fatal disease. That's because chest X-rays don't find these small nodules early, and most patients aren't diagnosed with lung cancer until they develop symptoms. When that happens, the disease is usually advanced and beyond the hope of cure with currently available treatments.