Interleukin-38 serum levels in breast cancer: A comparative analysis of women under 40 and over 50.

Background: Interleukin-38 (IL-38) is an anti-inflammatory cytokine with immunomodulatory properties, but its role in breast cancer (BC) is unclear. This study aimed to evaluate IL-38 serum levels in BC patients aged ≤40 and ≥50 years and to correlate the findings with clinicopathological features. Methods: IL-38 levels were measured using an enzyme-linked immunosorbent assay (ELISA) in the serum of 30 BC patients aged ≤40, 30 aged ≥50, and 30 healthy controls. Non-parametric tests were used for statistical comparisons, and Spearman's correlation was used to examine the correlation between IL-38 and age and tumor size. Results: There was no significant difference in serum IL-38 levels between patients aged ≥50 and those aged ≤40 or their age-matched controls. However, patients aged ≤40 years had significantly lower IL-38 levels than healthy individuals of the same age (P=0.003). In addition, serum IL-38 levels were significantly different between healthy individuals aged ≤40 and ≥50 years. Patients with stage I and II BC had significantly lower serum IL-38 levels than healthy controls (P=0.04 and P=0.003, respectively). However, there were no significant associations between IL-38 serum levels and histological grade (P=0.09), nuclear grade (P=0.11), lymphovascular invasion (P=0.72), perineural invasion (P=0.21), lymph node involvement (P=0.71) and tumor size (P=0.70). Conclusion: Our results suggest that any change in IL-38 serum levels is likely to affect the anti-inflammatory response in BC patients, especially those under 40 years of age. However, this is a preliminary study, and further studies with larger cohorts are needed to validate these findings.