Insufficient recruitment rate; technical issues with sample storage

Recent data have shown that the inadequate vitamin D status plays a role in the manifestation of the haematologic tumors and serum vitamin D level has a prognostic role also as it determines the tumor mortality. But data have not proved a causal relationship between the inadequate vitamin D status and the unfavourable outcomes so far. It is also still unknown, whether the normalization of vitamin D status in patient with vitamin D inadequacy is able to improve the prognosis and survival.

In this study the investigators examine the role of the adequate vitamin D substitution in the improvement of the outcomes of haematologic disorders.

Inclusion Criteria:

• at least 18 years old male or female
• chronic lymphoid leukaemia, any Rai stage
• 25-OH-Vitamin-D3 level between 10 and 30 ng/mL

Exclusion Criteria:

• serum calcium > 2,60 mmol/l
• 24 hour calcium urine excretion > 0,1 mmol/kg/day
• serum phosphate > 1,45 mmol/l
• eGFR < 30 ml/min/1,73m2
• nephrolithiasis
• receiving parenteral vitamin-D3 in past 6 months
• activated vitamin-D3 treatment