Transcript Abundance of IL6, CXCL9, LIF and LIFR in Glottic Lesions: Relationship to Histology and to Narrow-Band Imaging Vascular Patterns

Background: Narrow-band imaging (NBI) is an established adjunct in laryngeal lesion assessment, but the molecular processes underlying high-risk vascular patterns are poorly defined. We compared IL6, CXCL9, LIF, and LIFR transcript abundance between glottic carcinoma and non-cancerous lesions, related it to NBI patterns, and tested whether IL6 adds diagnostic information to NBI. Methods: In this prospective single-center exploratory study, 62 patients operated on for glottic lesions (33 squamous cell carcinomas, 29 non-cancerous lesions) underwent preoperative NBI (European Laryngological Society and Ni classifications); transcripts were quantified by RT-qPCR. Results: IL6 was higher in carcinoma (median 5.97 vs. 0.30; p = 0.004), also with non-detects set to the detection limit (p = 0.001) and among ever-smokers only (p = 0.0008). Sex adjustment attenuated the association (OR 1.78 per 10-fold increase, 95% CI 0.98–3.23; p = 0.06); smoking could not be adjusted for, as all carcinomas occurred in ever-smokers. CXCL9, LIF, and LIFR did not differ. Adding IL6 to NBI did not improve discrimination (ΔAUC 0.00–0.02; bootstrap 95% CIs including zero). Within non-cancerous lesions, IL6 was nominally higher in high-risk NBI patterns (n = 5–7), but no stratified comparison survived false-discovery-rate correction. Conclusions: IL6 transcript abundance was higher in glottic carcinoma, but the difference was sensitive to sex adjustment and, when measured in bulk tissue, may reflect lesion composition, including inflammatory infiltrate. IL6 showed no evidence of diagnostic value beyond NBI, and its link with vascular morphology remains a hypothesis.