Skin metastasis in patient with hairy cell leukemia: case report and review of literature.

The reported case of Hairy cell leukemia (HCL) refers to a 47-year-old man with pancytopenia, splenomegaly, a month and a half history of dyspnea on mild effort and in common daily activities and a purplish-brown cutaneous node on the back of the left hand at the time of hospital admission. Bone marrow aspiration showed an infiltration by a lymphoproliferative malignancy and the following cytochemical studies on bone marrow sample led to diagnosis of HCL. The biopsy of the skin lesion revealed a infiltrate of medium and large-size cells in the dermis with the the same cytologic features of leukemic blasts appearing in the bone marrow, upon which the diagnosis of Leukemia cutis was established. The differential diagnosis of leukemia includes other neoplastic hematopoietic disorders, such as lymphoma, myelodysplastic syndromes, multiple myeloma, aplastic anemia, severe megaloblastic anemia, severe lymphocytosis, severe monocytosis, and bone marrow failure. In our case, the skin lesion was surgically removed and then left to heal by secondary intention due to the presence of bacterial infection by Staphylococcus aureus and Streptococcus pyogenes. The wound was finally medicated to total healing with Promogran®, an advanced dressings which consists of a sterile, freeze-dried matrix composed of collagen and oxidised regenerated cellulose. The importance of our case lies in the fact that cases with association of HCL with leukemia cutis are very rare, and furthermore that after the excision of the skin lesion of the left hand, the surgeons heal to let the wound close by secondary intention.