Malignant tumours and psoriasis: climatotherapy at the Dead Sea.

In this retrospective, nation-wide cohort study, the risk of cancer was assessed for 1738 Danish patients with psoriasis subjected to climatotherapy at the Dead Sea during 1972-93, by linkage to the Danish Cancer Registry. The overall risk of cancer in patients treated at the Dead Sea (standardized incidence ratio, SIR = 1.59) was higher than that expected in the general population, owing to an excess risk of non-melanoma skin cancer (NMSC) [SIR = 4.