LEUKEMIC-CELLS WITHIN SKIN-LESIONS OF PSORIASIS IN A PATIENT WITH ACUTE MYELOGENOUS LEUKEMIA

We report on an 81-year-old man with acute myelo-monocytic leukemia (F AB M4) and a long-standing history of psoriasis, Biopsy of psoriatic p laques revealed the coexistence of characteristic histopathologic aspe cts of psoriasis together with an infiltrate of blasts with features o f myelo-monocytes, suggestive of a specific leukemic infiltrate within plaques of psoriasis. Immunohistologic stainings showed positivity of blasts for LN2 (CD74), MT1 (CD43), and lysozyme, consistent with a my eloid lineage of these cells. To the best of our knowledge, this is th e first report on the association of psoriasis with myelogenous leukem ia, The presence of leukemic cells within psoriatic skin plaques may b e explained by non-specific recruitment of recirculating malignant cel ls to the skin. Alternatively, as psoriasis is an inflammatory disease involving granulocytes among other cell types, it may be hypothesized that leukemic cells retain to some extent their capability to respond to physiologic stimuli and enter the skin in response to specific che motactic factors. (C) Munksgaard 1997.