For years, physicians and smokers have wondered whether medical scans could be used to detect lung cancer in its earliest stages, potentially saving thousands of lives.
Now, a study released today provides the most definitive answer yet, showing that screening of heavy smokers can indeed reduce deaths from lung cancer, a finding with major implications for the treatment of the cancer that kills more Americans than any other form.
The preliminary conclusions were made public last fall, but the new study in the New England Journal of Medicine presents the data in greater detail. Overall, the study of 53,000 current or former smokers showed that screening with a form of medical imaging known as low-dose CT cut lung cancer deaths by 20 percent. The study authors estimated that for every 320 people screened, one cancer death was prevented.
Cancer specialists and patient advocacy organizations cautioned that much remains to be determined, including official recommendations for who, exactly, should be screened, when, and how often, and whether insurance will cover the test. The new results do not mean everyone should seek lung cancer screening, nor do they suggest that it is safe to continue smoking because a test exists that might prevent some deaths. But Boston hospitals are preparing for calls and questions from patients — and some are offering the screening, even though it is not yet covered by most health insurance.
“Most of us treat people with advanced disease, and most of our patients die from it,’’ said Dr. Bruce Johnson, a lung cancer specialist at Dana-Farber Cancer Institute. “Having something introduced into our field that can cut down on the number of deaths by picking up cancer earlier and curing it is a paradigm changer.’’
Johnson, a board member of the American Society of Clinical Oncology, said professional organizations will now use the full data to formulate official screening recommendations. He added that if cost were not an issue and he was advising a friend or family member who was similar to study participants — they were 55 to 74 years old and current or former heavy smokers — he would recommend screening.
Brigham and Women’s Hospital recently started a lung cancer screening program that will be available at a community imaging center, Coolidge Corner Imaging in Brookline.
“For those who want to be screened — just like people did for mammography before there were guidelines — you can discuss it with your physician if you decide to book the appointment,’’ said Dr. Francine Jacobson, a thoracic radiologist at the Brigham and medical director for lung cancer screening at Coolidge Corner Imaging, where the screening will be available for $400.
At Mass. General, a low-dose CT screening program is also available, according to Dr. Lecia Sequist, an oncologist.
“Patients that have a doctor at MGH can have them order a screening CT, but they should check with their insurance to see if it’s covered so that they know the full situation before having the test,’’ Sequist wrote in an e-mail. The test will cost about $300 to $400, she said.
Dr. Thomas Lynch, director of the Yale Cancer Center, said the New Haven, Conn., hospital has already begun to set up a clinic to do such screens and respond to people who want the scan.
The guidelines on who should be screened are still being developed, as medical societies and federal agencies weigh the new data, but doctors said this was the beginning of a transformative shift in the treatment and prevention of lung cancer. Lung cancer kills about 160,000 people in the US each year. Because 7 million people in the U.S. fit the patient criteria used in the study, even a 20 percent decrease in deaths among that subset of heavy smokers could save thousands of lives.
The study is a first step; it shows deaths can be prevented with screening. Now analysts begin the delicate balancing of costs and benefits to determine how widely recommended the screening should be.
The new study had been eagerly awaited after a provocative study partially funded by a tobacco company first suggested that CT scans could prevent lung cancer deaths.
Today’s study revealed that there were a high number of false-positives in the low-dose CT screening, which required follow-ups that included invasive diagnostic procedures or further scanning. The study concluded that the risk of death from invasive follow-up procedures was “a rare occurrence.’’
The radiation exposure from CT scans poses some health risks, but doctors noted that the risk was much less for older patients like the ones in the study.
“This is the ‘mammogram’ for lung cancer we’ve been waiting for for years,’’ Lynch said. “The magnitude of reduction of the risk of death is as great as colonoscopy screening, and probably greater than mammograms.’’