[Paraneoplastic dermatoses]

Paraneoplastic dermatoses are important cutaneous markers of internal malignancies. They form a heterogenous group of skin diseases, where tumor induced immunologic factors, hormones, metabolic disorders and epidermal growth factor may play a role in the onset of the symptoms. The paraneoplastic skin disorder frequently refers to the type, localization and prognosis of the underlying tumor. The course of the tumor and that of the skin disease is generally parallel, which means that the cutaneous symptoms disappear when the tumor is treated and reappear in case of recurrence or metastasis. Seven rare obligate paraneoplastic dermatoses are known, where the skin marker is associated with neoplasia in almost 100% of the cases. The facultative paraneoplastic dermatoses are more common skin disorders, with a wider spectrum, and they are only associated with tumors in 3-30% of the cases. Authors present an overview of the clinical characteristics, etiopathogenesis and the underlying tumor of the most important paraneoplastic dermatoses.