Background: It is imperative to identify potential prognostic markers that predict recurrence of non-small cell lung cancer (NSCLC). Reactive oxygen species modulator 1 (Romo1) is a novel protein that regulates the production of intracellular reactive oxygen species.

Objective: Whether tissue Romo1 expression was associated with clinical outcomes in epidermal growth factor receptor (EGFR)-mutated and surgically resected lung adenocarcinoma.

Materials and Methods: A single-centered and retrospective study included 98 patients with EGFR-mutated and surgically resected lung adenocarcinoma from July 2008 to June 2021. Romo1 expression in tumor tissues was examined by immunohistochemistry and evaluated by histologic score (H-score). Univariate and multivariate analyses were performed to identify the clinicopathologic parameters associated with disease-free survival (DFS).

Results: High Romo1 expression was significantly associated with a more advanced stage (p <.0001). The median DFS of the high Romo1 group was significantly shorter than that of the low Romo1 group (31.2 vs 72.1 months, p <.0001), which is also confirmed through multivariate analysis (hazard ratio 2.63, 95% confidence interval 1.13?6.09, p = 0.0243).

Conclusions: Romo1 overexpression was associated with early recurrence in surgically-resected, EGFR-mutant lung adenocarcinoma. Therefore, our data highlight that Romo1 could be a potential predictive biomarker for this patient population.

Abbreviation: NSCLC= non-small cell lung cancer, Romo1= reactive oxygen species modulator 1, EGFR= epidermal growth factor receptor, H score= histologic score, DFS= disease-free survival