# Limited benefit of adjuvant chemotherapy for Asian patients with stage IB lung adenocarcinoma: implications for clinical practice

## TL;DR

Adjuvant chemotherapy benefits non-Asian but not Asian patients with stage IB lung adenocarcinoma, suggesting different treatment approaches may be needed for these populations.

## Contribution

This study reveals that adjuvant chemotherapy does not improve survival in Asian stage IB lung adenocarcinoma patients, unlike in non-Asian populations.

## Key findings

- Adjuvant chemotherapy improved overall survival in non-Asian but not Asian stage IB lung adenocarcinoma patients.
- Propensity score matching confirmed no benefit of adjuvant chemotherapy in Asian patients with high-risk features like VPI.
- Results from Chinese medical centers showed no improvement in disease-free or overall survival with adjuvant chemotherapy in Asian patients.

## Abstract

The benefit of adjuvant chemotherapy for patients with stage IB lung adenocarcinoma remains unclear. We compared adjuvant chemotherapy outcomes in Asian and non-Asian stage IB lung adenocarcinoma patients using multi-source clinical data.

Patients with stage IB lung adenocarcinoma from the 2004–2015 Surveillance, Epidemiology, and End Results (SEER) database and the 2020–2021 thoracic surgery department of three Chinese medical centers were included. Patients were divided into adjuvant chemotherapy and observation groups. Propensity score matching (PSM) was performed to reduce confounding bias. Survival curves were plotted and compared using the Kaplan–Meier method and log-rank test, respectively.

In the SEER data, 3408 patients met the inclusion criteria, overall survival (OS) was significantly better in the adjuvant chemotherapy group than in the observation group. In the non-Asian population, OS was significantly better in the adjuvant chemotherapy group, both before and after PSM. In the Asian population, OS did not significantly differ between the two groups before or after PSM. Among 690 patients from the three centers, disease-free survival (DFS) and OS in the adjuvant chemotherapy group were not better than those in the observation group, before or after PSM and in patients with high pathological grade or visceral pleural infiltration (VPI).

Adjuvant chemotherapy can significantly improve the prognosis of non-Asian patients with stage IB lung adenocarcinoma. In Asian patients, adjuvant chemotherapy does not improve prognosis, even in patients with high pathological grade or VPI.

The online version contains supplementary material available at 10.1186/s12957-025-03907-x.