Segmentectomy should be the standard surgical approach for patients with stage IA non-small cell lung cancer (NSCLC) who have small, peripheral tumors, according to researchers. 

Results of a phase 3 trial showed that segmentectomy prolongs 5-year overall survival (OS), when compared with lobectomy, in this patient cohort. These results were published in The Lancet.

In this phase 3 trial, researchers aimed to assess the noninferiority of segmentectomy to standard lobectomy in terms of OS in patients with clinical stage IA NSCLC tumors that were small (diameter of 2 cm or smaller; consolidation-to-tumor ratio less than 0.5) and peripheral (located in the outer one-third of the pulmonary parenchyma). 

Continue Reading

The study included 1106 patients in Japan who were randomly assigned to lobectomy (n=554) or segmentectomy (n=552). Ultimately, 22 patients assigned to segmentectomy were switched to lobectomies, and 1 patient underwent wide wedge resection. 

A minority of patients in both arms received postoperative adjuvant therapy — 67 in the lobectomy arm and 44 in the segmentectomy arm.

At baseline, the median age was 67 years in both arms (overall range, 32-85 years), 52.7% of patients were men, and 87.5% had adenocarcinoma histology. The patients had a median tumor diameter of 1.6 cm (range, 0.6-2.0 cm), and 50.0% had a consolidation-to-tumor ratio of 1.0.


The median follow-up was 7.3 years. The 5-year OS rate was 94.3% in the segmentectomy arm and 91.1% in the lobectomy arm (hazard ratio, 0.66; 95% CI, 0.47-0.93; P <.0001 for noninferiority, P =.0082 for superiority). 

The researchers observed a consistent OS benefit with segmentectomy vs lobectomy across all predefined subgroups. 

On the other hand, there was no improvement in relapse-free survival (RFS) with segmentectomy. The 5-year RFS rate was 88.0% for the segmentectomy arm and 87.9% for the lobectomy arm (hazard ratio, 0.99; 95% CI, 0.75-1.32; P =.9889). 

In fact, locoregional relapses occurred more frequently in the segmentectomy arm than in the lobectomy arm — 10.5% and 5.4%, respectively (P =.0018).

The rate of grade 2 or higher postoperative complications was similar following segmentectomy and lobectomy — 27% and 26%, respectively. No deaths were reported at 30 days or 90 days after surgery.

In a multivariate analysis, the predictors of pulmonary complications (including grade 2 or higher air leak and empyema) were complex segmentectomy (odds ratio, 2.07, 95% CI, 1.11-3.88; P =.023) and a smoking history of 20 pack-years or more (odds ratio, 2.61; 95% CI, 1.14-5.97; P =.023).

More patients died from causes other than lung cancer in the lobectomy arm than in the segmentectomy arm — 63% and 47%, respectively. The main causes of death were other cancers, respiratory disease, and cerebrovascular disease.

“To our knowledge, this study was the first phase 3 trial to show the benefits of segmentectomy versus lobectomy in overall survival of patients with small-peripheral NSCLC,” the researchers concluded. “The findings suggest that segmentectomy should be the standard surgical procedure for this population of patients.”

Disclosures: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of disclosures.


Saji H, Okada M, Tsuboi M, et al. Segmentectomy versus lobectomy in small-sized peripheral non-small-cell lung cancer (JCOG0802/WJOG4607L): A multicentre, open-label, phase 3, randomised, controlled, non-inferiority trial. Lancet. 2022;399(10335):1607-1617. doi:10.1016/S0140-6736(21)02333-3