FMOD expression in whole blood aids in distinguishing between chronic lymphocytic leukemia and other leukemic lymphoproliferative disorders. A pilot study.

BACKGROUND: Within the hematopoietic compartment, fibromodulin (FMOD) is almost exclusively expressed in chronic lymphocytic leukemia (CLL) lymphocytes. We set out to determine whether FMOD could be of help in diagnosing borderline lymphoproliferative disorders (LPD). METHODS: We established 3 flow cytometry-defined groups (CLL [n = 65], borderline LPD [n = 28], broadly defined as those with CLLflow score between 35 and -20 or discordant CD43 and CLLflow, and non-CLL LPD [n = 40]). FMOD expression levels were determined by standard RT-PCR in whole-blood samples. Patients were included regardless of lymphocyte count but with tumor burden ≥40%. RESULTS: FMOD expression levels distinguished between CLL (median 98.5, interquartile range [IQR] 37.8-195.1) and non-CLL LPD (median 0.012, IQR 0.003-0.033) with a sensitivity and specificity of 1. Most borderline LPDs were CD5/CD23/CD200-positive with no loss of B-cell antigens and negative or partial expression of CD43. 16/22 patients with available cytogenetic analysis showed trisomy 12. In 25/28 (89%) of these patients, FMOD expression levels fell between CLL and non-CLL (median 3.58, IQR 1.06-6.21). DISCUSSION: This study could suggest that borderline LPDs may constitute a distinct group laying in the biological spectrum of chronic leukemic LPDs. Future studies will have to confirm these results with other biological data. Quantification of FMOD can potentially be of help in the diagnosis of phenotypically complex LPDs.

Indications and use of, and incidence of major bleeding with, antithrombotic agents in myelodysplastic syndrome.

Myelodysplastic syndrome (MDS) and antithrombotic medication both increase the risk of bleeding. We set out to analyze the prevalence of use, indications and bleeding risk of antithrombotic therapy in patients with MDS in a retrospective, single-center study including all patients with MDS with >20 × 109/L platelets. 193 patients (59% male, median age 75 years) were included; 122 did not receive antithrombotic treatment, 51 received antiplatelet agents and 20 received anticoagulants. The cumulative incidence of major bleeding was higher in both the antiplatelet group (11.8% at 4 years, 95% confidence interval [95%CI]: 4.7-22.3%) and the anticoagulation group (21.2% at 4 years, 95%CI 6-42.5%) than in the control group (2.8% at 4 years 95%CI: 0.7-7.3%). The prevalence of use of antithrombotic medication in this cohort of patients with MDS was high and bleeding risk was increased in these patients.