Association of non-melanocytic tumors of the eyelid with demodex folliculorum

Purpose: Demodex is a parasite that lives in the hair follicles or sebaceous glands of the eyelid. There are two species that live in humans. These are Demodex follicularum and Demodex brevis. Demodex mites have been found to be associated with many inflammatory diseases such as blepharitis, chalazion, and rosacea. The role of the inflammatory environment in the pathogenesis of cancer development is also known. Our aim in this study was to investigate the role of Demodex mites and inflammation in eyelid tumors. Materials and methods: Basal cell carcinoma, squamous cell carcinoma, and tumor-free control tissues were included in our study. In these cases, the presence and number of Demodex and the presence and severity of inflammation were evaluated. In addition, the demographic characteristics of the tumors and prognostic data such as tumor size and invasion depth were evaluated. Results: No significant difference was found between the tumor and control groups in terms of the presence of Demodex. However, a significant relationship was found between the inflammation caused by Demodex mites in basal cell carcinomas and tumor size and invasion depth. Conclusion: Demodex mites may create an inflammatory tumor environment and play a role in tumor growth and progression.