Introduction: Laryngeal squamous cell carcinoma remains a major clinical challenge, and conventional margin assessment may overlook molecular alterations associated with residual disease and field cancerization. DUSP1, a regulator of MAPK signaling, may contribute to tumor behavior. This study aimed to assess DUSP1 expression levels in tumor and surgical margin samples of LSCC.

Material and methods: This descriptive cross-sectional study was conducted in 2024 at Tabriz University of Medical Sciences on 50 patients with laryngeal squamous cell carcinoma, selected through convenience sampling based on the Cochran formula for single-group studies. DUSP1 expression was measured in paired tumor and surgical margin samples, alongside demographic, clinical, and pathological variables, including age, sex, smoking status, tumor site, grade, TNM stage, lymph node involvement, and margin status.

Results: In this study of 50 patients with laryngeal squamous cell carcinoma, mean DUSP1 expression was significantly higher in tumor tissue than in paired surgical margins (2.73 ± 0.68 vs. 1.41 ± 0.37; P=0.001). Tumoral DUSP1 expression was also greater in smokers, poorly differentiated tumors, advanced-stage disease, node-positive cases, and positive surgical margins, indicating a consistent association between elevated DUSP1 levels and more aggressive clinicopathological characteristics.

Conclusion: DUSP1 was significantly overexpressed in LSCC tumor tissue compared with surgical margins and was associated with adverse clinicopathological features. These findings suggest that DUSP1 may serve as a promising molecular indicator of tumor aggressiveness and local disease extension.