Pityriasis lichenoidesPopadić, Svetlana (Avtor) inflammatory diseasepityriasis lichenoidespolymorphous inflammatory diseasepruritusrare skin diseaseIntroduction: Pityriasis lichenoides (PL) predominantly affects children and young adults. Its etiology is unclear, and the condition ranges from a harmless inflammatory disease to possible progression or pre-manifestation of cutaneous T-cell lymphoma. Methods: A long-term cohort included 242 patients with PL of all age groups diagnosed and treated at our department from 2009 to 2019. Follow-up lasted until 2024. We analyzed the disease duration, demographic and clinical features, and outcomes in our patients. Results: The cohort of PL patients studied included 107 adults and 135 children. A total of 221/242 (91%) patients were followed for 5 to 15 years (the median follow-up period was 9.9 years). No statistically significant difference (p > 0.05) in disease duration or lesion distribution was found between different PL forms in children or adults. The results show a male-to-female ratio of 1.7:1 for pediatric patients and 0.6:1 for adults, with a higher incidence of male patients among children (p < 0.01). During the follow-up period, no progression to cutaneous T-cell lymphoma was established. Conclusions: PL encompasses a spectrum of papulosquamous disorders with male predominance among children and female predominance in adults. In addition, the study results underscore the benign course of PL.Združenje slovenskih dermatovenerologov20252026-06-09 08:38:23Neznano29915slNa spletni strani revije navedeno: Acta Dermatovenerologica Alpina, Pannonica et Adriatica (ISSN 1318-4458) is an open access medical journal published quarterly by the Association of Slovenian Dermatovenerologists (https://acta-apa.mf.uni-lj.si/index.php); Authors publishing in our journal retain copyright of their work under the Creative Commons Attribution License (CC BY 4.0). This license allows unrestricted use, distribution, and reproduction of the work in any medium, provided the original author(s) and copyright holder(s) are appropriately credited, and the original publication in the journal is properly cited, following established academic practices (https://acta-apa.mf.uni-lj.si/submissions.php).