title: Cutaneous extramedullary hematopoiesis in a patient with idiopathic myelofibrosis.
abstract: Idiopathic myelofibrosis (IM) is a chronic myeloproliferative disorder and some cases of IM have extramedullary hematopoiesis. Extramedullary hematopoiesis is commonly seen in the liver, spleen and lymph nodes, but cutaneous extramedullary hematopoiesis (CEH) is very rare in cases of IM. We report a case of CEH in a 65-year-old Japanese woman with IM. This patient had many hard brownish nodules on her chest, abdomen and scalp. Histopathological examination of the nodule on her chest showed the existence of various stages of immature erythrocytes, leukocytes and megakaryocytes indicating that these hard nodules showed extramedullary hematopoiesis in the dermis. The proliferation of these immature cells in the dermis plays an important role in the pathogenesis of CEH. CEH is a very rare manifestation of IM and progresses slowly.
authors.affiliation: Department of Dermatology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan. tosikomi@med.kitasato-u.ac.jp
authors.forename: Toshiko
authors.initials: T
authors.lastname: Miyata
authors.forename: Mikio
authors.initials: M
authors.lastname: Masuzawa
authors.forename: Kensei
authors.initials: K
authors.lastname: Katsuoka
authors.forename: Masaaki
authors.initials: M
authors.lastname: Higashihara
mesh_terms: D000368:Aged; D005260:Female; D006411:Hematopoiesis, Extramedullary; D006801:Humans; D055728:Primary Myelofibrosis / Q000150:complications* / Q000473:pathology; D012871:Skin Diseases / Q000209:etiology* / Q000473:pathology*