A pair of editorials published online this week in JAMA Internal Medicine took another look at the evidence and issues facing the Centers for Medicare & Medicaid Services (CMS) as it prepares to make a final decision on coverage for low-dose CT screening for lung cancer. Coming from both sides of the issue, the articles offer a set of closing arguments, in a sense, to the ongoing coverage debate.

Douglas E. Wood, MD, of the University of Washington in Seattle, takes the position that current evidence supports a benefit of lung cancer screening with low-dose CT for current and former smokers at high risk, and he argues that a screening program that is patient-centered and minimizes unintended harms could be responsibly implemented.

“Since 70 percent of lung cancer occurs in patients 65 years or older, CMS should cover low-dose CT, thus avoiding the situation of at-risk patients being screened up to age 64 through private insurers and then abruptly ceasing screening at exactly the ages when their risk for developing lung cancer is increasing,” wrote Wood, alluding to the fact that under the Affordable Care Act, private insurers will be compelled to cover screening.

Wood summarized the findings of the National Lung Screening Trial (NLST), which was stopped early when an interim analysis demonstrated a 20 percent lung cancer mortality benefit from screening. Follow up analyses did recalculate the overall benefit down slightly—to 16 percent benefit—but also revealed that women receive a substantially greater benefit and that the mortality benefit was similar for patients whether they were younger or older than 65 years, according to Wood.

The 320 individuals needed to screen to save one life with lung cancer screening also compares favorably with the 2,000 needed to screen to save one life from breast cancer and the 1,200 needed to screen with regard to colon cancer, explained Wood.

When it comes to minimizing risks of screening, Wood wrote that screening should be limited only to those at high risk of developing lung cancer and that an evidence-based algorithmic approach should be used to manage lung nodules.

Arguing for more caution before covering screening in the Medicare population, Steven H. Woolf, MD, MPH, of Virginia Commonwealth University in Richmond, and colleagues wrote that CMS should not offer coverage until better data becomes available.

“Until better data are available for older adults who are screened in ordinary (nontrial) community settings, CMS should postpone coverage of low-dose CT screening for Medicare beneficiaries,” wrote Woolf et al. They noted that 73 percent of NLST participants were younger than 65 and the benefit-harm ratio could vary markedly based on age.

They outlined four reasons for caution:

• The magnitude of benefit from widespread low-dose CT screening is uncertain, Woolf and colleagues argue, because current estimates are based on only one study and some follow up simulations.
• Harms of screening could affect a large population as more than one-third of U.S. adults are current or former smokers. This means that many could undergo imaging and face the potential harms of false-positives, anxiety, radiation exposure and procedure complications.
• The specific conditions of the NLST (protocols, screening participants, screening setting, etc.) would rarely exist in routine practice.
• Ultimately, the decision to screen and whether benefits outweigh harms is a judgment call, with the U.S. Preventive Services Task Force recommended shared decision making between patient and physician before screening is ordered.

While Woolf and colleagues suggest the best course of action is for CMS to postpone a coverage decision until better data is available, they did say that if Medicare were to cover low-dose CT screening, it should place conditions on coverage. Potential conditions included limiting the number of screens, offering coverage only following documented shared decision making with patients, and making centers document proper qualifications and referral protocols.

Following the publication of the dueling editorials, the American College of Radiology issued a statement criticizing the article from Woolf et al, saying it relied on “unsubstantiated or ambiguous claims and fails to accurately portray the current state of CT lung cancer screening.”

The ACR pointed out that subsequent analysis of NLST results showed that screening works similarly well for those over 65 as it does for those who are younger, and that two published studies have shown CT lung cancer screening is cost-effective in the Medicare population and the privately insured.

“Questions regarding CT lung cancer screening effectiveness, cost and patient acceptance are answered. Obfuscation of current screening capabilities and the lifesaving benefit of these exams is not helpful and may ultimately cost lives. It is time for Medicare to move forward with full coverage for low-dose CT lung cancer screening,” said Ella Kazerooni, MD, FACR, chair of the American College of Radiology Lung Cancer Screening Committee and American College of Radiology Thoracic Imaging Panel.

In April, the Medicare Evidence Development & Coverage Advisory Committee voted that it had low confidence that there is adequate evidence saying screening benefits outweighed harms in a Medicare population. A final decision from CMS is expected in 2015.