Blood Testing for Lung Cancer May Address Inadequate Screening Utilization

Despite the fact that early detection of lung cancers significantly improves survival, low-dose computed tomography (CT) utilization is significantly lower compared with screening for other cancers, according to Ali H. Zaidi, MD.

CancerNetwork spoke with Zaidi, medical director of Esophageal and Lung Research at the Allegheny Health Network Cancer Institute, about how lung cancer screening would be enhanced through the use of cell-free DNA (cfDNA) liquid biopsy, FirstLook.

He contrasted the prognosis for patients based on how early lung cancer is detected, with lung cancer detected at stage I associated with a 5-year survival rate greater than 55% and a survival rate of less than 5% for late-stage lung cancers. Furthermore, he emphasized a need to increase utilization of screening for lung cancer to match other cancers. He illustrated this by explaining that screening rates for breast, cervical, colorectal, and prostate cancers fell between 60% and 70%, whereas screening rates for lung cancers falls between 5% and 10%.

Zaidi then listed reasons why a common lung cancer screening system, low-dose CT, had low utilization rates. The most prominent concern is a stigma around smoking, which Zaidi claims results in underreporting of smoking, and which may subsequently make patients ineligible for screening. Additionally, Zaidi underscored a plethora of issues impacting utilization, which include perceived lack of insurance, a lack of standardized screening protocols across health care systems, and patient fear of radiation exposure.

Regarding adoption, Zaidi highlighted an accessibility and capacity issue. He explained that scheduling concerns; including lack of same-day availability for screening, scheduling delays, and patients attaining time off from work; may prevent patients from utilizing low-dose CT. Zaidi concluded by expressing that low lung cancer screening rates was an unmet need that might be met with noninvasive blood tests for lung cancer screening.

Transcript:

If you look at the extent of the problem, at the combined numbers from other cancers which are routinely screened, which include breast, cervical, colorectal, and prostate cancer, the combined numbers are less than people who die from lung cancer. We also know that typically, if lung cancer is detected late, the 5-year survival rate is less than 5%. If it is detected as stage I disease, 5-year survival rates are up above 55%. There is a huge unmet need and an impact we can do by finding patients early.

Unfortunately, low-dose CT [...] adoption has been lagging. The adoption rates for low-dose CT are in the 5% to 10% range. Now, if you look at other established screening programs, their screening rates are between 60% to 70%. There is a lot of room for improvement.

The reason why there are some natural barriers associated with the screening guidelines, [is due to] stigma associated around smoking. Many people who, in the lung cancer screening guidelines, unlike other cancers, which are just screened based on age categories, we have a documented smoking history requirement of 20 pack years. This is an issue because of the stigma associated with smoking. [Often] people underreport it, or it is not captured appropriately within our electronic health records by physicians. These patients may be deemed as ineligible. This is a big issue.

Then there are others, like perceived lack of insurance. Then we have non standardized protocols for screening implemented across the different health systems. When you come to look at low-dose CT, people are concerned about radiation exposure. These are perceived misconceptions.

In addition to that, there is a big issue with adoption, primarily because low-dose CT programs have a capacity issue as well as an access issue. These patients who need to be scheduled for low-dose CT, they lack availability of same-day appointments, [they experience] scheduling delays––logistics around going in for a scan, getting time off from work and things like that, which impact the click rate. There is definitely a huge unmet clinical need and to fill these gaps and shortfalls, noninvasive blood tests has good potential.