Bone marrow involvement in cutaneous mastocytosis

Background Cutaneous mastocytosis is considered a relatively benign and ind olent form of mast cell disease, which either ultimately regresses, remains stable or is only slowly progressive. Previously, it has been purported th at no more than 60% of adult patients with cutaneous mastocytosis will have occult bone marrow involvement. Objectives To investigate the frequency of bone marrow involvement in patie nts with mastocytosis but without systemic symptoms. Methods Bone marrow aspirate and trephine biopsy were performed in 13 conse cutive patients with cutaneous mastocytosis attending our department. Results All but one of these patients had evidence of bone marrow involveme nt. Bone marrow cytogenetic abnormalities have been found in patients with cutaneous mastocytosis: all our patients who were analysed showed a normal karyotype. Conclusions Bone marrow involvement is common in adults with cutaneous mast ocytosis.