# Segmentectomy Versus Wedge Resection for Stage IA Lung Adenocarcinoma—A Population-Based Study

## TL;DR

This study finds that segmentectomy improves survival for larger early-stage lung tumors compared to wedge resection, based on a large population dataset.

## Contribution

The study fills a knowledge gap by comparing two sublobar resection techniques for stage IA lung adenocarcinoma using a population-based approach.

## Key findings

- Segmentectomy was associated with better overall survival than wedge resection for tumors larger than 2 cm.
- For tumors smaller than 2 cm, segmentectomy and wedge resection had comparable outcomes.
- Younger age and smaller tumor size were linked to better survival outcomes.

## Abstract

This study utilizes Taiwan’s robust cancer registry to compare segmentectomy and wedge resection for Stage IA lung adenocarcinoma, the most common type of lung cancer. Results indicate that segmentectomy improves survival for tumors over 2 cm. Notably, this research addresses a critical gap in the knowledge left by two landmark trials, JCOG0802 and CALGB140503. While these trials established the non-inferiority of sublobar resection to lobectomy for small tumors, they did not definitively answer the question of whether segmentectomy or wedge resection is the superior sublobar approach. This study’s strength lies in its large, representative sample and rigorous propensity score matching, enabling reliable conclusions and informing individualized treatment strategies. By providing insights into the optimal surgical technique within the sublobar resection category, this research contributes valuable knowledge with the potential to improve patient care and inform future investigations.

Background: Sublobar resection (SLR), including segmentectomy and wedge resection (WR), is an alternative to lobectomy for early-stage lung cancer due to its potential benefits in preserving lung function. However, the comparative outcomes between segmentectomy and WR for stage IA lung adenocarcinoma are equivocal. This population-based study aimed to compare overall survival between segmentectomy and WR. Methods: Data on patients with clinical stage IA lung adenocarcinoma were collected from the Taiwan Cancer Registry between 2011 and 2018. The primary endpoint was overall survival. Further subgroup survival analyses were conducted based on tumor size. Propensity score matching (PSM) was used to balance baseline differences such as age and tumor stage between the two groups. Predictors of survival other than the surgical procedure were analyzed using a Cox regression model. Results: In total, 6598 patients with stage IA lung adenocarcinoma undergoing SLR between 2011 and 2018 were enrolled, including 2061 and 4537 receiving segmentectomy and WR, respectively. The mean age was 60.3 ± 11.7 years, 66.2% were female, and 81.5% never smoked. After PSM, segmentectomy was associated with significantly better overall survival than WR (p = 0.019), especially for tumors larger than 2 cm (p < 0.001). Aside from segmentectomy, age ≤ 75 years, well-differentiated tumors, small tumor size, and the absence of nodal metastasis were associated with better overall survival. Conclusions: Segmentectomy offered superior overall survival for patients with tumors larger than 2 cm. For tumors smaller than 2 cm, the outcomes of segmentectomy and WR were comparable, offering flexibility in surgical decision-making. These findings highlight the need for individualized surgical approaches based on tumor characteristics.