Premium
The risk of thrombosis in essential thrombocythemia is associated with the type of CALR mutation: A multicentre collaborative study
Author(s) -
Pérez Encinas Manuel M.,
Sobas Marta,
GómezCasares María Teresa,
Abuin Blanco Aitor,
Noya Pereira María Soledad,
Raya José María,
AndradeCampos Marcio M.,
Álvarez Larrán Alberto,
Lewandowski Krzysztof,
Łukasz Szukalski,
Hernández Boluda Juan Carlos,
FerrerMarín Francisca,
Fox María Laura,
Gołos Aleksandra,
Gasior Kabat Mercedes,
Magro Mazo Elena,
Czyż Anna,
Martín Martín Alejandro,
Bellosillo Paricio Beatriz,
Quinteiro García Celsa,
González Martín Jesús María,
Stuckey Ruth
Publication year - 2021
Publication title -
european journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.904
H-Index - 84
eISSN - 1600-0609
pISSN - 0902-4441
DOI - 10.1111/ejh.13561
Subject(s) - essential thrombocythemia , medicine , gastroenterology , thrombosis , venous thrombosis , incidence (geometry) , calreticulin , risk factor , oncology , polycythemia vera , genetics , biology , physics , optics , endoplasmic reticulum
Objectives In patients with essential thrombocythemia (ET), after the JAK2 V617F driver mutation, mutations in CALR are common (classified as type 1, 52‐bp deletion or type 2, 5‐bp insertion). CALR mutations have generally been associated with a lower risk of thrombosis. This study aimed to confirm the impact of CALR mutation type on thrombotic risk. Methods We retrospectively investigated 983 ET patients diagnosed in Spanish and Polish hospitals. Results With 7.5 years of median follow‐up from diagnosis, 155 patients (15.8%) had one or more thrombotic event. The 5‐year thrombosis‐free survival (TFS) rate was 83.8%, 91.6% and 93.9% for the JAK2 V617F, CALR ‐type 1 and CALR ‐type 2 groups, respectively ( P = .002). Comparing CALR ‐type 1 and CALR ‐type 2 groups, TFS for venous thrombosis was lower in CALR ‐type 1 ( P = .046), with no difference in TFS for arterial thrombosis observed. The cumulative incidence of thrombosis was significantly different comparing JAK2 V617F vs CALR ‐type 2 groups but not JAK2 V617F vs CALR ‐type 1 groups. Moreover, CALR‐ type 2 mutation was a statistically significant protective factor for thrombosis with respect to JAK2 V617F in multivariate logistic regression (OR: 0.45, P = .04) adjusted by age. Conclusions Our results suggest that CALR mutation type has prognostic value for the stratification of thrombotic risk in ET patients.