Gelatinous bone marrow transformation in a case of idiopathic myelofibrosis: a morphological paradox.
A 74-year-old woman with severe, but asymptomatic weight loss was found to have splenomegaly, thrombocytosis, and neutrocytosis. A trephine biopsy showed a hypercellular bone marrow with a proliferation of abnormal megakaryocytes, mild reticulin fibrosis, and osteosclerosis, i.e., features of an early stage of idiopathic myelofibrosis. In contrast to this predominant pattern, the marrow also contained a distinct hypocellular focus of gelatinous transformation (GMT) in which hematopoietic and fat cells were replaced by gelatinous substances that were characterized as hyaluronic acid mucopolysaccharides histochemically. GMT is a rare disorder of unknown pathogenesis, and is an unspecific indicator of severe illness which most often occurs in patients with a background of weight loss. This is the first reported case of gelatinous changes in an otherwise fibrotic bone marrow, a constellation which a priori seemed to be incompatible.
Böhm
J
J
Institute of Pathology, University of Freiburg, Germany. jboehm@ukl.uni-freiburg.de
Schmitt-Gräff
A
A
D000273:Adipose Tissue / Q000473:pathology; D000368:Aged; D001853:Bone Marrow / Q000378:metabolism / Q000473:pathology*; D017809:Fatal Outcome; D005260:Female; D005780:Gelatin; D006801:Humans; D006820:Hyaluronic Acid / Q000378:metabolism; D010026:Osteosclerosis / Q000473:pathology; D055728:Primary Myelofibrosis / Q000378:metabolism / Q000473:pathology*
D005780:Gelatin; D006820:Hyaluronic Acid