UNLABELLED: The etiology of papilloma formation is multifactorial. There is a strong association between human papillomavirus (HPV) and the development of these conjunctival lesions. HPV is tumorigenic and commonly produces benign tumors with low malignant potential. Papillomas rarely go through malignant transformation. MATERIAL AND METHODS: Retrospective study of patients with a diagnosis of conjunctival papilloma or squamous cell carcinoma. RESULTS: From a collection of 125 patients with conjunctival non-pigmented tumours in the period from 2007 to 2017, in 119 (95.2%) patients histological examination confirmed papilloma and in 6 (4.8%) patients it confirmed carcinoma. Of the total number of patients, 39 were women (31.2%) and 86 men (68.8%). The mean age of patients was 68.4 years (range 20-94 years). Localization of lesions: bulbar conjunctiva - 65 (52.0%), upper eyelid tarsal conjunctiva + fornix - 6 (4.8%), lower eyelid + fornix - 27 (21.6%), caruncle - 20 (16.0%) and plica semilunaris - 7 (5.6%) patients. In the patient cohort we recorded 2 papillomas that were transformed into squamous cell carcinoma. HPV16 was positive in these patients, the carcinomas were from the area of the bulbar conjunctiva, and the surgical solution was associated with the perioperative administration of Mitomycin C. In one case, the inverted papilloma developed into orbital carcinoma within 2 years of primary excision, and the patient underwent radical surgical procedure (partial exenteration of the orbit) followed by radiotherapy. CONCLUSION: Transformation of the papilloma into the carcinoma is rare, but it must always be taken into consideration in case of a recurrence of the disease. HPV can infect the conjunctiva. The ophthalmologist, in collaboration with a pathologist, may recommend appropriate laboratory tests to confirm the diagnosis. Long-term outpatient follow-up of patients after excision of the conjunctival papilloma is also necessary. Key words: epibulbar tumors, conjunctival tumors, papilloma, carcinoma.

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