[Skin disorders as markers of internal disease. Paraneoplastic dermatoses]

Paraneoplastic dermatoses are markers of internal malignancy characterised by being relatively uncommon, associated with certain forms of cancer and occurring in connection with the cancer either before, during, or after the diagnosis has been made. Furthermore, the skin symptoms typically run a parallel course with the cancer. Most paraneoplastic dermatoses disappear when the primary tumour is removed and reappear in the case of recurrence or metastases of the cancer. Adult dermatomyositis is especially associated with breast and lung cancer. Necrolytic migratory erythema is seen in patients with a glucagon-producing tumour in the pancreas. Bazex's syndrome is associated with cancer in the upper respiratory and digestive tracts. Erythema gyratum repens is an annular erythema associated with lung, breast, stomach and oesophageal cancer. Acquired hypertrichosis lanuginosa, which is extremely rare, is a specific marker of internal malignancy, especially lung and colon cancer. Acanthosis nigricans and Leser-Trélat's sign are cutaneous markers of stomach cancer. Sweet's syndrome is in some cases associated with acute myeloid leukaemia, but not as frequently as formerly believed. Acquired ichthyosis, scleromyxoedema, amyloidosis, paraneoplastic pemphigus, woody hands, and Trousseau's syndrome are mentioned.