By Linda Carroll

Current lung cancer screening guidelines may need to be less restrictive when it comes to African American smokers, a new study suggests.

Researchers found that cutoff criteria that work for white smokers may lead to missed cancers in blacks, according to the report in JAMA Oncology.

“Our current lung cancer screening guidelines are woefully inadequate in providing equal opportunity for African Americans to be eligible for screening,” said Melinda Aldrich, an assistant professor at the Vanderbilt University Medical Center in Nashville, Tennessee, who led the study.

“It’s time to move the needle. If the guidelines continue as they are, they will potentially exacerbate racial disparities in lung cancer outcomes.”

The new study, which looked at new lung cancer cases in a predominantly low-income and black population, found that under criteria in current U.S. Preventative Services Task Force (USPSTF) guidelines, many African Americans diagnosed with lung cancer would not have been eligible for early screening because they didn’t have a high enough number of cigarettes or years of smoking in their history.

To take a closer look at how the criteria impacted black smokers, Aldrich and her colleagues turned to data from the Southern Community Cohort Study, an ongoing observational research project designed to examine health disparities in low-income African Americans.

Between March 25, 2002 and September 24, 2009, the SCCS enrolled 84,522 adults, of whom some 48,000 were current or former smokers: 32,463 of them black and 15,901 white. Researchers followed the participants until December 31, 2014, by which time 1,269 new lung cancers had been diagnosed.

Participants had been asked about their lifetime smoking history, which researchers quantified in “pack years,” the number of packs of cigarettes a smoker consumed daily multiplied by the number of years they smoked. So, for example, two packs per day for one year or one pack a day for two years would equal two pack years.

The current guidelines suggest lung cancer screening for smokers with 30 pack years or more. Aldrich would like to see that lowered. “This (study) is a wakeup call for the community to make people aware who are currently evaluating the guidelines,” she said.

Among the black participants who were current or former smokers, half had about 25 pack years or more, and only 17% would qualify for screening under the current guidelines, while among whites, half had 48 pack years or more and 31% would qualify for screening.

Among people diagnosed with lung cancer during the study period, 32% of the black and 56% of the white participants would have qualified for screening.

While commending the Vanderbilt team on their research, cancer experts said the issue is more complicated than simply altering a pack-year cutoff.

“As the authors point out, the Task Force recommendations were made on the basis of data that did not include adequate representation of African Americans, so this type of study is important to help us identify and address sources of racial inequality in cancer screening,” said Jaimee Heffner, an assistant member of the cancer prevention program at the Fred Hutchinson Cancer Research Center in Seattle, Washington.

“The study results are a red flag that we should pay attention to, but it would be premature to recommend changing the guidelines on the basis of this study alone,” Heffner said in an email. “We need to consider not just the potential benefits, but also the potential harms, like false positive results and complications from invasive diagnostic procedures. It’s not clear how earlier initiation of screening at lower pack-year levels for African Americans would impact the benefit-to-harm ratio.”

You factor in the dangers associated with the screening, agreed Dr. Otis Brawley, Bloomberg Distinguished Professor at the Johns Hopkins Kimmel Cancer Center in Baltimore, Maryland. “For every 5.4 patients saved, one is lost due to a hospital- or screening-based intervention,” he said.

The task force’s recommendations were based on studies “at 32 of the finest hospitals in the U.S.,” Brawley said. “You have to wonder what the data would be in a county hospital in Georgia, for example, and what the lung cancer screening benefit-to-risk ratio would be at an average hospital in the U.S.”

SOURCE: JAMA Oncology, online June 27, 2019.