The Thorny Question of Early Diagnosis in Lung Cancer: Should the IP-10 Cytokine be Brought to Trial?

[BACKGROUND] Lung cancer remains the leading cause of cancer mortality worldwide, underscoring the need for non-invasive early diagnostic tools. IP-10, a cytokine involved in inflammation and angiogenesis, is a promising candidate. The present study aims to assess the relevance of IP-10 in lung cancer early diagnosis.

[METHODS] In this cross-sectional study, we measured serum IP-10 levels using Luminex assays in 52 treatment-naïve lung cancer patients without comorbidities and 14 healthy controls. Based on the non-normal distribution of data, group comparisons were performed using Wilcoxon rank-sum tests. Multivariate linear regression was used to adjust for cofounders.

[RESULTS] IP-10 levels were significantly elevated in lung cancer patients compared to healthy controls (median: 189.69 pg/mL vs. 108.78 pg/mL, p = 0.001). This significance persisted in the early-stage subgroup (stages 0-IIA; median: 192.49 pg/mL vs. 108.78 pg/mL, p = 0.001), even after multivariate adjustment (p = 0.018). Levels peaked in evolved early-stage disease (median: 241.42 pg/mL) before declining in advanced stages, while remaining elevated above controls.

[DISCUSSION] The rise in IP-10 levels in early-stage lung cancer patients emphasizes its potential to serve as an early diagnostic biomarker. Meanwhile, the peak-and-decline pattern during phases of disease is consistent with its postulated dual role in early antitumor immunity and later tumor promotion.

[CONCLUSION] IP-10 can potentially be used as a supplemental serum biomarker for early lung cancer diagnosis. This finding calls for additional validation in bigger, multi-center cohorts to define diagnostic thresholds and investigate their incorporation into multi-marker panels.