In patients with BCR-ABL-negative myeloproliferative neoplasms (MPN), arterial or venous thromboembolic events (ATE/VTE) are a major burden. In order to control these complications, vitamin K antagonists (VKA) are widely used. There is no robust evidence supporting the use of direct oral anticoagulants (DOAC) in MPN patients. We therefore compared the efficacy and safety of both anticoagulants in 71 cases from a cohort of 782 MPN patients. Seventy-one of 782 MPN patients (9.1%) had ATE/VTE with nine ATE (12.7%) and 62 VTE (87.3%). Forty-five of 71 ATE/VTE (63.4%) were treated with VKA and 26 (36.6%) with DOAC. The duration of anticoagulation therapy (p = 0.984), the number of patients receiving additional aspirin (p = 1.0), and the proportion of patients receiving cytoreductive therapy (p = 0.807) did not differ significantly between the VKA and DOAC groups. During anticoagulation therapy, significantly more relapses occurred under VKA (n = 16) compared to DOAC treatment (n = 0, p = 0.0003). However, during the entire observation period of median 3.2 years (0.1–20.4), ATE/VTE relapse-free survival (p = 0.2) did not differ significantly between the two anticoagulants. For all bleeding events (p = 0.516) or major bleeding (p = 1.0), no significant differences were observed between VKA and DOAC. In our experience, the use of DOAC was as effective and safe as VKA, possibly even potentially beneficial with a lower number of recurrences and no increased risk for bleedings. However, further and larger studies are required before DOAC can be routinely used in MPN patients.

In patients with bcr‐abl‐negative myeloproliferative neoplasms (MPN), concerns are often raised about the use of anticoagulants because of an increased bleeding risk. However, there are few MPN studies focusing on bleeding. To investigate bleeding complications in MPN, we report our retrospective, single‐center study of 829 patients with a median follow‐up of 5.5 years (range: 0.1–35.6). A first bleeding event occurred in 143 of 829 patients (17.2%), corresponding to an incidence rate of 2.29% per patient/year. During the follow‐up period, one out of 829 patients (0.1%) died due to bleeding. Regarding anticoagulation, most bleeding occurred in patients on antiplatelet therapies (60.1%), followed by patients on anticoagulation therapies (20.3%) and patients not on anticoagulation (19.6%). In multivariate analysis, administration of antiplatelet (HR 2.31 [1.43, 3.71]) and anticoagulation therapies (HR 4.06 [2.32, 7.09]), but not age, gender or mutation status, was associated with an increased bleeding risk. Comparing the “probability of bleeding‐free survival” between the MPN subtypes, no significant difference was observed (p = 0.91, log‐rank test). Our retrospective study shows that antiplatelet and anticoagulation therapies significantly increase the risk of bleeding in MPN patients without affecting mortality. However, there is no reason to refrain from guideline‐conform primary or secondary anticoagulation in MPN patients.

Objectives Pregnancies in women with polycythemia vera (PV) are associated with an increased risk of PV‐related maternal complications and often result in miscarriage. Recommendations for the management of PV pregnancies are mainly based on studies with a small number of patients. A correlation between pregnancy outcome and postpartum course has been reported for essential thrombocythemia, but corresponding data for PV are lacking so far. Methods In 41 PV pregnancies, the pregnancy outcome, the use of PV‐specific therapies (ie, acetylsalicylic acid, low‐molecular weight heparin and/or interferon‐alpha), and the postpartum PV course were investigated. Results A live birth rate of 51.2% (21/41 pregnancies) was observed. 43.9% of pregnancies ended in spontaneous abortion and 4.9% in stillbirth. A significantly increased live birth rate occurred in pregnancies with PV‐specific therapies compared to standard antenatal care (69.0% vs. 8.3%; P < .0019). The use of PV‐specific therapy significantly increased the number of maternal hemorrhages (P = .021) without increasing the risk of fetal complications. During the median postpartum follow‐up period of 1.2 years (range 0.1‐13.7), complicated postpartum PV occurred significantly more often after miscarriages (P = .035). Conclusions According to our analysis, PV‐specific therapy improved the live birth rate. Significantly more complicated postpartum PV courses were observed after miscarriages.

Recently, there has been increased concern about a risk of secondary malignancies (SM) occurring in myelofibrosis (MF) patients receiving ruxolitinib (RUX). In polycythemia vera (PV), on the other hand, only limited data on the risk of SM under RUX treatment are available. To investigate the association between RUX therapy in PV and SM, we conducted a retrospective, single-center study that included 289 PV patients. RUX was administered to 32.9% (95/289) of patients for a median treatment duration of 48.0 months (range 1.0–101.6). Within a median follow-up of 97 months (1.0–395.0) after PV diagnosis, 24 SM occurred. Comparing the number of PV patients with RUX-associated SM (n = 10, 41.7%) with the 14 (58.3%) patients who developed SM without RUX, no significant difference (p = 0.34, chi square test) was found. No increased incidences of melanoma, lymphoma, or solid “non-skin” malignancies were observed with RUX (p = 0.31, p = 0.60, and p = 0.63, respectively, chi square test). However, significantly more NMSC occurred in association with RUX treatment (p = 0.03, chi-squared test). The “SM-free survival” was not significantly different by log rank test for all 289 patients (p = 0.65), for the patients (n = 208; 72%) receiving cytoreductive therapy (p = 0.48) or for different therapy sequences (p = 0.074). In multivariate analysis, advanced age at PV diagnosis (HR 1.062 [95% CI 1.028, 1.098]) but not administration of RUX (HR 1.068 [95% CI 0.468, 2.463]) was associated with an increased risk for SM (p = 0.005). According to this retrospective analysis, no increased risk of SM due to RUX treatment could be substantiated for PV.