Dermatológia pre prax 4/2025
Rare skin cancers – primary cutaneous lymphomas
Primary cutaneous lymphomas (PCLs) are defined as non-Hodgkin lymphomas that occur in the skin without evidence of extraneous disease at the time of diagnosis. According to the cells of their origin, we distinguish between cutaneous T-cell lymphomas (CTCL) and cutaneous B-cell lymphomas (CBCL). The different subtypes of PCL differ in their prognosis and are classified according to the criteria of the World Health Organization (WHO) in its latest revised 5th edition of skin and haematopoietic tumours from 2022. Diagnosis and classification are based on a combination of clinical, histological, immunophenotypic and genetic data. Demonstrating a clonal T-cell receptor or immunoglobulin gene rearrangements in skin lesions or peripheral blood helps to establish a diagnosis, but clinical and histopathological features are the most important factor in planning treatment. Dermal lymphoid hyperplasia and atypical lymphocytic infiltrate require strict distinction from malignant lymphoma. Due to the rare occurrence of PCL, patients with this diagnosis should be managed by a multidisciplinary team of dermatologists, pathologists, haematologists and radiation oncologists.
Keywords: cutaneous T- and B-cell lymphomas, mycosis fungoides, Sézary syndrome, staging, treatment, cutaneous pseudolymphomas
