Brendan T. Heiden, MD, MPHS

Adhering to surgical quality metrics may improve overall survival and recurrence-free survival for patients with early-stage non-small cell lung cancer (NSCLC) who undergo resection with curative intention, according to findings published in JAMA Surgery.

“We sought to understand what defines a ‘high-quality’ or ‘good’ lung cancer operation,” Brendan T. Heiden, MD, MPHS, told Physician’s Weekly. “In particular, we were interested in understanding the relationship between various surgical quality metrics, like avoiding a delayed operation and sampling the correct number of lymph nodes, and long-term outcomes among patients with lung cancer receiving curative-intent surgery.”

Dr. Heiden and colleagues conducted a retrospective cohort study using data from US veterans diagnosed with stage 1 NSCLC who underwent surgery between October 2006 and September 2016. They determined five surgical quality metrics according to current treatment standards, including timely surgery, minimally invasive approach, anatomic resection, adequate lymph node sampling, and negative surgical margin. Based on the association between these metrics and overall survival, the researchers developed a surgical quality score that was then validated with data from the National Cancer Database. They also assessed the link between surgical quality score and recurrence-free survival.

Overall Survival Increases With More Quality Metrics Met

The study included 9,628 veterans (mean age, 67.6; 96.4% men). Most patients (82.7%) were White and slightly more than half of the cohort (58.4%) identified as current smokers at the time of surgery. Approximately half of the tumors (53.3%) were adenocarcinomas and most had higher-grade features (tumor grades II-IV; 81.7%).

Regarding the quality metrics defined by the researchers, most patients underwent timely surgery (68.9%), including lobectomies (71.1%) or wedge resections (21.8%); segmentectomy was performed in fewer patients (5.5%). The most widespread surgical approach was thoracotomy (58.6%), followed by minimally invasive surgery (41.4%). Adequate nodal sampling (defined as ≥10 lymph nodes) was attained in 3,278 patients (34.0%), and most procedures (96.7%) resulted in negative surgical margins.

Dr. Heiden and colleagues developed an integer-based score, termed the Veterans Affairs Lung Cancer Operative quality (VALCAN-O) score by the researchers, ranging from 0 (no quality metrics met) to 13 (all metrics met). Higher scores indicated progressively better risk-adjusted overall survival.

Median overall survival varied between score ranges (0-5 points: 2.6 years; 6-8 points, 4.3 years; 9-11 points, 6.3 years; and 12-13 points, 7.0 years; P<0.001). Risk-adjusted recurrence-free survival improved in a stepwise manner between score categories (multivariable-adjusted HR for 6-8 vs 0-5 points, 0.62 [P<0.001]; 12-13 vs 0-5 points, 0.39 [P<0.001]). In the validation cohort, which included 107,674 non-veterans, the score retained its association with overall survival.

‘Substantial Improvement’ in Surgical Quality Measures

The study “demonstrates that what happens in the operating room can dramatically impact long-term outcomes after lung cancer surgery,” Dr. Heiden says.

It also emphasizes “the critical importance of adhering to evidence-based surgical quality metrics when treating early-stage lung cancer,” he continues. “Efforts to standardize and optimize these surgical quality parameters may disproportionately impact long-term survival rates among patients with lung cancer receiving surgery.”

Dr. Heiden notes that “further efforts are needed to ensure that guideline-concordant treatment parameters are followed as frequently as possible in surgical practice settings across the US” while “applauding” the thoracic oncology community.

“Our results demonstrated a substantial improvement in surgical quality measures over the last decade,” he says. “This is particularly important as new, exciting treatments continue to be discovered in the lung cancer arena.”