Spleen enlargement is a risk factor for thrombosis in essential thrombocythemia: Evaluation on 1,297 patients

Abstract

Spleen enlargement, present in 10–20% of Essential Thrombocythemia (ET) patients at diagnosis, is a feature clinically easy to assess, confirmable by echography with a very low chance of misinterpretation. Nonetheless, the clinical and prognostic role of splenomegaly has been seldom evaluated. From 1979 to 2013, 1297 ET patients retrospectively collected in the database of the Lazio Cooperative Group and Bologna University Hospital were evaluable for spleen enlargement at diagnosis and included in the analysis. On the whole, spleen was enlarged in 172/1297 (13.0%) patients; in most cases (94.8%) splenomegaly was mild (≤5 cm). Patients with splenomegaly were younger, predominantly male, presented higher platelet count and JAK2V617F allele burden and had a lower incidence of concomitant cardiovascular risk factors. At least one thrombotic event during follow‐up occurred in 97/1,125 (8.6%) patients without spleen enlargement compared to 27/172 (15.7%) patients with spleen enlargement (P = 0.003). Despite comparable use of cytoreductive/antiplatelet therapies in the two groups, the cumulative risk of thrombosis at 5 years was significantly higher in patients with baseline splenomegaly (9.8% versus 4.4% in patients without splenomegaly, P = 0.012). In multivariate analysis exploring risk factors for thrombosis, splenomegaly retained its negative prognostic role, together with previous thrombosis, leucocyte count and male gender. Baseline splenomegaly seems to be an independent additional risk factor for thrombosis in nonstrictly WHO‐defined ET patients. This data could be useful in the real‐life clinical management of these patients. Am. J. Hematol. 91:318–321, 2016. © 2016 Wiley Periodicals, Inc.

Splanchnic vein thrombosis in myeloproliferative neoplasms: risk factors for recurrences in a cohort of 181 patients

“…This result is consistent with other observations reporting a role of splenomegaly for new episodes of thrombosis in patients without SVT as well, 29, 30 even though this finding has not been confirmed by other researchers. 31 It has been speculated that splenomegaly should be considered an index of more intensive myeloproliferation; however, its association with recurrent SVT may also be due to a more extensive occlusion of the hepatic-portal venous axis.…”

Assessing the thrombotic risk of patients with essential thrombocythemia in the genomic era

“…In a large retrospective analysis (N = 1297) splenomegaly was independently associated with the occurrence of thrombotic events. 43 This finding, however, was not confirmed in a similar study (N = 560), perhaps due to differences in diagnostic criteria used and/or length of follow-up. 44 …”

Characteristics and outcomes of young adults with Philadelphia‐negative myeloproliferative neoplasms

“…Splenomegaly as a prothrombotic factor was described in different series across all age groups. 32,33 Our study has several limitations; it is retrospective, and it lacks a comparison group. Furthermore, mutations in CALR and MPL which are routinely done in current practice were not available in most patients.…”