[Pyoderma gangrenosum and hemopathies. Apropos of 2 cases].

Pyoderma gangrenosum (PG) is an uncommon ulcerative disease of the skin. The cause is unknown but the condition is often associated with other diseases such as rheumatoid arthritis, ulcerative colitis, Crohn's disease or monoclonal gammopathy. The association between PG and haematological malignancies (acute leukaemia, Myeloproliferative disorders) is infrequent.