The usage of low-dosage CT scans to screen for lung cancer has grown over the past decade, to the point where it is recommended by major health organizations for not just the most at-risk populations, but some of the low-risk ones as well.
However, as Memorial Sloan Kettering head of thoracic oncology Paul Paik, M.D., told his virtual audience at July’s Black Health Matters Summit, more information is needed on how effective the usage is for diagnosing the disease among Black patients. The flaw is familiar to medical researchers in every field: clinical trials that still do not represent all demographics.
The 2011 study that led to the increase in CT scan usage in lung cancer screening had about 53,000 participants, Paik said, but only some 4.5 percent were African American. The main culprit was proximity to the trial location, he said, illustrating his point with a map of the areas that matched high-concentration areas of lung cancer among Black patients, with widespread lack of access to screening-related trials.
“You see big deserts, big patches, where there is no clinical trial access, where there is a significant proportion of African Americans who have been diagnosed with lung cancer,’’ Paik said. “So this gets at the issue, again, of disparity; it gets at the issue of proximity, it gets at the issue of why we’re talking about this (now).’’
Memorial Sloan Kettering Cancer Center’s Lung Cancer Screening Program helps solve the problem in its geographic area, and the center’s website and that of other cancer advocacy organizations can direct potential participants to available trials.
In addition, Paik is leading two phase II clinical trials at the center for drugs to treat non-small-cell lung cancer, the most common version of the disease.
The effort to get the screening to the most people possible is absolutely worth it, Paik said, because according to the 2011 study, the CT scanning has led to 20 percent fewer lung cancer-related deaths as compared to diagnoses revealed through conventional chest X-rays.
The Memorial Sloan Kettering screening program focuses on patients aged 55 to 80 who have smoked the equivalent of one pack a day for 30 years, and are either current smokers or have quit within the past 15 years. Research still indicates that having quit for 15 years or more decreases the chances of a lung cancer diagnosis, Paik said.
With that, he added, the percentage of that form of lung cancer among non-smokers, or very light or long-stopped smokers (“collegiate smokers,’’ Paik called that category) remains stubbornly high.
Even with the number of smokers continuing to decrease, the percentage of non-smokers diagnosed stays around 20 percent, and that complicates results of studies of CT screening, because they fall outside of the high-risk category. Paik said researchers continue to work to find ways to best use CT screening to bring that number down.
One of the larger concerns of those considering CT screening, Paik said, was the level of radiation—but, he said, the test lasts just about 10 minutes, and the exposure is roughly the same as “if you fly from New York to California and back.’’
More of an obstacle, he said, was the still-widespread, historically grounded skepticism from Black potential trial participants that they are being used as lab experiments. More open communications with, and from, their health-care providers can ease that skepticism, he said.
“The decision-making process is going to be a shared one,’’ Paik said. “It’s something that you’ve got to feel comfortable with. It has to make sense for you.’’
—David Steele
