Factor XIII Subunit A Immunohistochemical Expression is Associated With Inferior Outcomes in Acute Promyelocytic Leukemia

Coagulation factor XIII subunit A (FXIIIa) intracellular expression has been described in platelets, megakaryocytes, monocytic cells, and leukemic blasts. Flow cytometric-based studies have suggested prognostic implications of FXIIIa expression, especially within the acute promyelocytic leukemia (APL) subgroup of acute myeloid leukemia (AML); however, its prognostic correlate by immunohistochemistry (IHC) is unknown. The aims of this study were to (1) define the clinicopathologic features of FXIIIa IHC-positive AML and (2) compare APL with other AML subtypes. Eighty-seven bone marrow biopsies or clot/particle preparations from our institution were evaluated with FXIIIa IHC. The study cohort consisted of bone marrow evaluations of 36 consecutive pretherapy APL, 42 selected pretherapy non-APL AML, and 9 negative staging cases. FXIIIa IHC expression was correlated with clinical and pathologic features and overall survival (OS). Leukemic blast FXIIIa cytoplasmic positivity was noted in 56% (20/36) APL and 74% (31/42) non-APL AML (P=0.10). FXIIIa IHC expression was associated with inferior OS within the APL cohort (P=0.04). No OS differences were noted in comparing FXIIIa IHC expression in all AML (P=0.17), or FXIIIa IHC expression within favorable, intermediate or adverse cytogenetic groups (P=0.14, 0.22 and 0.87, respectively). FXIIIa IHC expression is observed among a broad spectrum of AML subtypes and is not characterized by specific pathologic features. However, within the AP...
Source: Applied Immunohistochemistry and Molecular Morphology - Category: Chemistry Tags: Research Articles Source Type: research