Comparison of the prognoses of laryngeal preneoplastic lesions based on Ljubljana and World Health Organization classifications.

BACKGROUND: The aim of this study is to evaluate the prognosis of patients with laryngeal preneoplastic lesions based on Ljubljana classification (LC), Revised LC, World Health Organization Dysplasia System (WHO-DS) 2005 and WHO-DS 2017. METHODS: Patients diagnosed with a laryngeal preneoplastic lesion in our clinic between 2005 and 2018 were included in the study. Biopsy preparations of patients were reexamined by the pathology unit and classified based on LC, Revised LC, WHODS 2005, and WHO-DS 2017. Patients with carcinoma were identified during follow-up. The prognosis of preneoplastic lesions was statistically analyzed based on carcinoma development and duration using these four different classifications. RESULTS: Carcinoma developed in 16 of 142 patients after repeated biopsy. The risk for carcinoma development was found to be more statistically significant in atypical hyperplasia than in squamous cell hyperplasia and basal-parabasal cell hyperplasia according to LC (p: 0.027 and 0.035), no statistically significant difference was observed between squamous and basal-parabasal cell hyperplasia and CIS groups. The risk of carcinoma development was more statistically significant in high-grade squamous intraepithelial lesion (SIL) than in low-grade SIL according to revised LC (p: 0.04); in severe hyperplasia than in other groups according to WHO-DS 2005; and in highgrade dysplasia than in low-grade dysplasia according to WHO-DS 2017 (p: 0.013). The Cox regression analysis demonstrated that the risk of developing carcinoma statistically increased with age in all classifications, independent of the severity of dysplasia (p < 0.01). According to Cox regression analysis, there was no effect of sex on carcinoma development. DISCUSSION: : In revised classifications, such as the revised LC and WHO-DS 2017, it is seen that facilitating clinical use is achieved by reducing the number of subgroups by combining the subgroups that do not statistically differ in terms of carcinoma development.