Real-World Practice Upholds Lobectomy for Early-Stage Lung Cancer

LOS ANGELES — Surgeries to remove small tumors in stage IA non-small cell lung cancer (NSCLC) were associated with varying odds of long-term survival depending on the amount of lung removed, based on real-world data collected from across the country.

In routine practice, unadjusted 10-year overall survival (OS) for lobectomy reached 44.8%, while for segmentectomy it was 44.2%, and for wedge resection 41.4%, according to Christopher Seder, MD, of Rush University Medical Center in Chicago, at the annual meeting of the Society of Thoracic Surgeons (STS).

Lobectomy was associated with a significantly lower risk of all-cause mortality relative to sublobar resections in general (HR 0.87, 95% CI 0.83-0.92), though on closer inspection, this was really an advantage over wedge resections (HR 0.84, 95% CI 0.80-0.88) but not segmentectomy (HR 0.96, 95% CI 0.88-1.03). Segmentectomy was associated with fewer deaths than wedge resection (HR 0.88, 95% CI 0.81-0.95), Seder’s group reported.

“This research is a significant step forward in understanding the long-term implications of surgical choices for lung cancer patients. Using real-world data to complement [randomized controlled trial] findings offers surgeons additional context for tailoring treatment strategies,” Seder said in a press release.

The study was based on the STS General Thoracic Surgery Database. Findings were similar for lung cancer-specific survival, according to the authors.

For early-stage NSCLC, lobar resection has been the gold standard since 1995 with publication of the LCSG trial. Given that many people do not meet criteria or cannot tolerate the procedure, however, there are alternatives in the less invasive sublobar resection surgeries, namely wedge resection or segmentectomy.

Some research goes as far as to suggest that sublobar resections are the new standard of care for selected patients.

In 2022, the CALGB randomized trial showed that sublobar resection performed as well as lobectomy for NSCLC tumors ≤2 cm. Around the same time, the JCOG 0802 trial reported that, in patients with NSCLC ≤2 cm, segmentectomy was not inferior to lobectomy in terms of the primary endpoint of OS.

Seder pointed out the questionable generalizability of these studies. JCOG included 44% never-smokers and mostly adenocarcinoma, and the median forced expiratory volume in 1 second was over 2L. CALGB was characterized by strict inclusion criteria, upfront node dissection, and confirmation of N0 status by means of frozen-section examination.

Thus, his group opted to perform a study using real-world data.

“I want to stress that these data should not be seen as contradictory to the CALGB trial or the JCOG trial, but instead complementary,” Seder told the audience. He pointed out that in the real world, 20% of wedge resections don’t have nodal dissections and there is overall less station sampling.

“The take-home message here is really that if you expect trial results, the very strict selection criteria that are used on-trial need to be applied in the intraoperative protocol of sending your nodes first and so on and so forth,” he said.

The ostensibly inferior results of the wedge resection group also prompted session discussant John Mitchell, MD, of the University of Colorado School of Medicine in Aurora, to ask what the data might suggest about other treatments such as stereotactic body radiotherapy (SBRT) for NSCLC.

Seder responded with the advantages of surgery, citing the surgeons’ track records of safety and lymph node dissections that can help pathology reporting. “However, is SBRT worse than a wedge [resection] with 1 mm margin and one node taken? I can’t say for sure.”

He urged that thoracic oncology teams put more patients on trials trying to answer the question of whether the alternative forms of treatment are better than lung surgery, especially for high-risk patients.

The STS database used for the present study covered 346 participating institutions, with data spanning the years 2012 to 2022. Included were 32,340 adults undergoing lung resection surgery for clinical stage IA NSCLC 2 cm or smaller, excluding high-risk patients.

In the registry cohort, 61.2% underwent lobectomy, 13.2% segmentectomy, and 25.6% wedge resection.

To determine the long-term vital status of these patients, the investigators linked the STS database to national death and hospitalization records from the CDC and CMS.

In sensitivity analyses excluding pathologic-upstaged cases, Seder and colleagues found that lobectomies were associated with improved long-term survival versus sublobar resection, wedge resection, and segmentectomy.

Seder acknowledged the study’s potential for residual confounding. “There are multiple factors that may affect long-term survival that are not collected and cannot be accounted for,” he cautioned.