Why Are Oncologists Deviating From Best Evidence in Stage III NSCLC?

Two years ago at the World Conference on Lung Cancer, investigators proudly declared concurrent chemoradiation (cCRT) followed by consolidation durvalumab as a new standard of care in stage III non–small cell lung cancer (NSCLC). Many outside experts agreed. Yet when I recently reviewed a web-based survey of practicing US medical oncologists' approach in this setting, I was struck by the discordance between what the literature tells us is best evidence-based treatment and the varied practices described by the survey's 150 respondents.

Multidisciplinary discussion is key for guiding treatment decisions in this indication, yet respondents said they presented only 55% of patients at live or virtual tumor boards. Despite the guidance offered by the PACIFIC trial, cCRT was used for only 48% of patients and, when actually administered, was followed by durvalumab for only 55%. Two thirds of the respondents reported a preference for consolidation chemotherapy following cCRT in a subset of patients, even though evidence indicates that such an approach adds toxicity and provides no demonstrated improvement in efficacy.

Of course, survey results are not actual practice data. However, we would expect that self-reported results would have a bias toward greater conformity with evidence-based standards rather than against them. And although these results were derived from a limited sample of oncologists, respondents had significant experience in managing lung cancer and were overall representative of US practice, with 82% based in community settings and 18% in academic centers.

There are several factors, though, why these results diverge from evidence-based consensus. Clinical trials may set new standards, but they often fail to address how difficult it is to implement these approaches in real-life cancer care.

Oncology practices have varied degrees of available resources, and many community-based cancer centers have poor access to even a general oncology tumor board.

Stage III NSCLC is remarkably heterogeneous,and those surveyed reported that patients were often too frail and had too many comorbidities to pursue cCRT, or that patients themselves declined to undergo it for various reasons, primarily toxicity concerns.

There is also an array of practical barriers, ranging from limited support from other specialists to patients' inability to comply with recommended treatments due to restrictions on their time based on travel, work, or family.

Additionally, data from a post-hoc subset analysis of PACIFIC revealed no benefit from durvalumab in patients with tumors demonstrating programmed death ligand 1 (PD-L1) expression < 1% or whose tumor harbors an EGFR mutation. Although this unplanned analysis drew from a limited number of patients and had notable imbalances between the arms, it nonetheless leaves durvalumab's efficacy in certain patients an open question that may be reflected in these survey results.

Finally, as new trial data are shared at a remarkable pace, there is a potential lag time before practice changes, particularly among oncologists who treat many types of cancer every day.

Devika Das, MD, a hematologist-oncologist who is section chief at the VA hospital affiliated with the University of Alabama at Birmingham, and a member of the American Society of Clinical Oncology's International Quality Task Force, confirmed that such variables may indeed contribute to care falling outside the clinical guidelines. The way to address this, she said, is to help practices develop personalized approaches.

"Having solutions that are tailored to individual practices, helping individual practices recognize their barriers while giving them tools to work with, is probably the best way to address the disparities in lung cancer care delivery," said Das, who is currently finishing her master's degree in healthcare quality and safety, with the focus of her research on how to evaluate and overcome gaps in delivery of optimal cancer care for oncology practices.

In recent years, researchers have highlighted great advances in the treatment of NSCLC, yet obstacles remain in ensuring that these then become routine in appropriate patients. Understanding where and why we're falling short requires turning our attention to the delivery of care and identifying the specific barriers for different practices. Only with these efforts can we tackle the individualized solutions needed to deliver cancer care that is as close to the best evidence-based practices that patients can get.

H. Jack West, MD, associate clinical professor and executive director of employer services at City of Hope Comprehensive Cancer Center in Duarte, California, regularly comments on lung cancer for Medscape. Dr West serves as web editor for JAMA Oncology, edits and writes several sections on lung cancer for UpToDate, and leads a wide range of continuing education programs and other educational programs, including hosting the audio podcast West Wind.

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