麻豆传媒

CHICAGO -- A system of scoring lung lesions observed in screening studies was reviewed here by researchers for the American College of Radiology (ACR) who hope the new tool will be as successful for lung cancer screening as ACR's BI-RADS has been for breast cancer.

"We wanted to make the LungRADS as familiar to radiologist as BI-RADS so we continued to use a scale of 0-4," explained , professor of radiology and chair of the Radiology Service Excellence Program at the University of Michigan, Ann Arbor.

LungRADS was released in April 2014, and is expected to be used in compiling data on patients in line with lung screening diagnoses and in mandated registries, Kazerooni said here during a Hot Topics session at the 100th anniversary meeting of the Radiological Society of North America. She said the program will be rolled out in January.

She outlined the categories of lesions detected with CT scans during the screening process:

• Category 0: Incomplete -- refers to incomplete studies that cannot be evaluated due to technical or missing information. These patients should have additional lung cancer screening CT images and/or comparisons to prior chest CT examinations if needed.
• Category 1: Negative – refers to findings of no nodules and definitely benign nodules. Patients should continue to have annual screening with low-dose CT.
• Category 2: Benign appearance or behavior – refers to nodules with a very low likelihood of becoming a clinically active cancer due to size or lack of growth. Patients should continue to have annual screening with low-dose CT.
• Category 3: Probably benign – refers to probably benign findings but a short-term follow-up is suggested; includes nodules with a low likelihood of becoming a clinically active cancer. Patients should be screened every 6 months with low-dose CT.
• Category 4A and 4B: Suspicious – refers to findings for which additional diagnostic testing and/or tissue-sampling is recommended. In 4A, patients should have low-dose CT at 3 months; PET/CT may be used when there is an 8-mm or larger solid component to a lesion. In 4B, patients should undergo chest x-ray, PET/CT and/or tissue sampling depending on the probability of malignancy and comorbidities. PET/CT may be used when there is an 8-mm or larger solid component.

The categories also come with modifiers, Kazerooni explained. An "S" modifier suggests the screening examinations discover "clinically significant or potentially clinically significant finding that are non-lung-cancer" such as emphysema. A "C" modifier refers to patients with prior diagnoses of lung cancer who return for screening.

Kazerooni said that LungRADS also describes how nodule size, nodule consistency, benign and benign behavior versus active cancer can further narrow the cases, and perhaps reduce the false positive findings from one in four cases, as seen in the National Lung Screening Trial (NLST), to one in 10 cases.

Reducing those false positives is critical, she said because "40% of the National Lung Screening Trial subjects had at least one false positive over 3 years. Among patients with a positive screen who underwent a diagnostic procedure, 1.4% experienced a complication."

LungRADS was built on the NLST outcomes that showed early screening of asymptomatic at-risk individuals could detect early-stage lung cancer and could lead to a 20% decrease in lung cancer mortality and a 6.9% decrease in all-cause mortality. That was followed by a recommendation by the U.S. Preventive Service Task Force to screen people 55-79 years old with a cumulative smoking history of at least 30 pack-years and who still smoke or who have quit smoking in the past 15 years.

Kazerooni said that, although the LungRADS offers a guide to the likelihood of cancer, the ACR guidelines still state that "[t]he best way to reduce lung cancer is to stop smoking." The guidelines also indicate that, in order to receive accreditation, a program "must have a mechanism in place to refer patients for smoking cessation counseling or to provide smoking cessation materials."

The HotTopics session also featured speakers who described the ongoing negotiations on the maze of regulations and reimbursements for the screening program, as well as the integrated efforts between researchers, clinicians, and patient advocates that helped win official endorsements of routine screening.

Comment