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Updated: Jul 18, 2026

Transduction-Transplantation Mouse Model of Myeloproliferative Neoplasm
Published on: December 22, 2016
Synovial tumefactive extramedullary hematopoiesis associated to polycythemia vera
Hugo Alvarez-Argüelles Cabrera1, José Luis Carrasco Juan, María Candelaria García Castro
1Department of Pathology, Canary University Hospital, Tenerife, Canary Islands, Spain.
Abstract:
The case of a 66-year-old male patient with a chronic myeloproliferative type polycythemia vera disorder, who after 2 years of evolution is developing a tumefactive extramedullary hematopoiesis (TEH) located in the synovial of the articulation in the right knee, is described. The tumor histologically consists of a relatively lax and edematous synovial structure diffusely infiltrated by mature and semimature hematopoietic cellular population. The simultaneous study of the bone marrow reveals medullar spaces full of hematopoietic cellularity, with a predominance of megakaryocytic and red series, and with the addition of severe reticulin fibrosis, facts that suggest a progression toward myelofibrosis. The TEH developed in tissues without a reticulum endothelial system is very uncommon. We provide data about the first case located in the synovial membrane and we review the literature regarding this pathologic entity.
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