The effects of hematopoietic stem cell transplant on splenic extramedullary hematopoiesis in patients with myeloproliferative neoplasm-associated myelofibrosis.
Publication/Presentation Date
9-1-2016
Abstract
BACKGROUND/OBJECTIVE: Hematopoietic stem cell transplant (HSCT) is the only curative treatment for myeloproliferative neoplasm-associated myelofibrosis (MPN-MF). The main clinical manifestation of MPN-MF is splenomegaly secondary to extramedullary hematopoiesis (EMH). The effects of HSCT on splenic EMH and associated vascular and stromal changes are unknown. This study compares the findings seen in spleens following HSCT with those of nontransplanted patients, normal controls, and matched bone marrow (BM) samples.
METHODS: This study included three transplanted MPN-MF spleens, three nontransplanted MPN-MF spleens, and three normal controls. Spleens were assessed for: (a) presence/extent of EMH; (b) presence of Gamna-Gandy bodies; (c) splenic fibrosis; (d) CD34-positive microvessel density; (e) CD8-positive sinusoids; (f) frequency of smooth muscle actin-positive myoid cells; and (g) nerve growth factor receptor-positive adventitial reticulum cells. In two cases, matched BM samples were assessed for cellularity, presence of atypical megakaryocytes, and fibrosis.
RESULTS: Compared with normal controls, all MPN-MF spleens were larger in size, had EMH, red pulp fibrosis, higher CD34-positive microvessel density, and decreased CD8-positive sinusoids. Compared with nontransplanted cases, post-HSCT spleens showed disappearance or reduction of EMH. Gamna-Gandy bodies were increased; no differences in the remaining parameters were found. A reduction of splenic EMH was associated with normalization of BM cellularity and megakaryopoiesis.
CONCLUSION: HSCT reduces/abrogates splenic EMH and is associated with an increased number of Gamna-Gandy bodies, which may suggest vascular damage. The lack of stromal changes in spleens removed shortly after transplant is in line with similar observations in the BM, where a longer interval is often necessary for resolution of fibrosis.
Volume
9
Issue
3
First Page
96
Last Page
104
ISSN
2589-0646
Published In/Presented At
Pizzi, M., Gergis, U., Chaviano, F., & Orazi, A. (2016). The effects of hematopoietic stem cell transplant on splenic extramedullary hematopoiesis in patients with myeloproliferative neoplasm-associated myelofibrosis. Hematology/oncology and stem cell therapy, 9(3), 96–104. https://doi.org/10.1016/j.hemonc.2016.07.002
Disciplines
Medicine and Health Sciences
PubMedID
27521149
Department(s)
Department of Medicine, Hematology-Medical Oncology Division, Lehigh Valley Topper Cancer Institute
Document Type
Article