[Classification and pathogenesis of cutaneous paraneoplastic syndromes].

The associations between skin conditions and malignant tumours are reviewed and classified in two groups: indirect associations (predisposing genetic factor or carcinogenic agent), and direct associations with parallel evolutions corresponding to the true paraneoplastic syndromes. Occasional associations are also mentioned. The cutaneous paraneoplastic syndromes can be classified according to their pathogenic mechanisms, although these are mostly hypothetical, allowing those of secretory, immunological, deficient and neurovascular origins to be distinguished.