Prognostic Irrelevance of Vitamin D Insufficiency in Myeloproliferative Neoplasms and De Novo Myelodysplastic Syndromes
Authors: Pardanani Animesh , Drake Matthew T. , Finke Christy , Lasho Terra L , Rozell Shaina A , Jimma Thitina , Tefferi Ayalew 
Published: October 2019

Abstract
Abstract 5158

Background:
Vitamin D insufficiency is commonly observed in clinical practice. Observational studies have suggested an association of vitamin D insufficiency with increased risk of cancer development. Further, vitamin D insufficiency has been associated with poorer prognosis in solid tumors as well as hematologic malignancies, including non-Hodgkin lymphoma and chronic lymphocytic leukemia. In this study, we examined the clinical and prognostic correlates of low plasma levels of 25-hydroxyvitamin D (25[OH]D), which reflects whole-body vitamin D stores, in a cohort of myeloproliferative neoplasm (MPN) and myelodysplastic syndrome (MDS) patients.

Methods:
We studied a total of 409 patients: 247 (60%) had primary myelofibrosis (PMF), 74 (18%) de novo MDS, 63 (15%) polycythemia vera (PV) and 25 (6%) essential thrombocythemia (ET). Inclusion criteria required availability of archived plasma, bone marrow aspirate and biopsy and cytogenetic information at the time of first referral to our institution. Vitamin D measurements were performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). For the purposes of this study, plasma 25(OH)D levels <10 ng/mL indicated severe deficiency, <25 ng/mL insufficiency, and 25–80 ng/mL optimal levels.

Results:
Patient characteristics were as follows: (i) PMF: median age=63 years, >65 years=41%, males=68% and serum creatinine above the upper normal limit (UNL)=15%; (ii) MDS: median age=72 years, >65 years=77%, males=69% and creatinine >UNL=12%; (iii) PV median age=61 years, >65 years=37% and males=50%; and (iv) ET: median age=48 years, >65 years=10% and males=28%.
Median (range) plasma 25(OH)D levels (ng/mL) were as follows: PMF 25 (0–60), PV 27 (6.8–51), ET 31 (6–50) and MDS 30 (7.7–72) (p=0.005). The proportion of patients with 25(OH)D insufficiency were: PMF 48%, PV 43%, ET 28% and MDS 28% (p=0.01). Similarly, the proportion of patients with severe 25(OH)D deficiency were: PMF 9%, PV 3%, ET 12% and MDS 1% (p=0.05).
In PMF and MDS, 25(OH)D insufficiency was not significantly correlated with age (≤65 vs. >65 years), gender, red cell transfusion need, DIPSS-plus/IPSS category, hemoglobin (<10 vs. ≥10 g/dL), thrombocytopenia (<100 vs. ≥100 × 109/L), circulating blasts, unfavorable karyotype, serum creatinine >UNL, or JAK2V617F (PMF only) (p>0.05).
25(OH)D insufficiency was not predictive of inferior overall survival (OS) in PMF, MDS, PV, or ET (p>0.05). Similarly, in PMF and MDS, 25(OH)D insufficiency was not predictive of inferior leukemia-free survival (LFS) (p>0.05). Severe 25(OH)D deficiency was infrequently observed in MDS or PV patients; in PMF or ET patients, there was no prognostic impact of severe 25(OH)D deficiency on OS or LFS (p>0.05).

Conclusions:
Vitamin D insufficiency is relatively common in PMF, PV, ET and de novo MDS however this finding had no prognostic value for OS in the aforementioned patients. In PMF and MDS patients, low 25(OH)D levels had no clearly identifiable clinical correlates and further did not have prognostic value for LFS.

Disclosures:
No relevant conflicts of interest to declare.