A study of the prevalence of vitamin K deficiency in patients with cancer referred to a hospital palliative care team and its association with abnormal haemostasis.

BACKGROUND: Many patients with advanced cancer are malnourished. Anorexia is common, as is the use of chemotherapy, which may cause nausea and poor appetite. Ten per cent of these patients experience haemorrhagic events.

AIM: Since vitamin K deficiency (VKD) causes bleeding, to establish the prevalence of VKD in patients with advanced cancer receiving palliative care.

METHODS: Serum concentrations of vitamin K(1) and undercarboxylated factor II (PIVKA-II) were determined in 46 (17 male/29 female) inpatients aged 26-85 (mean 58) years. INR and liver function tests (bilirubin, ALT, GGT and ALP) were also performed.

RESULTS: Vitamin K(1) was below the lower limit of the reference range (0.33 nmol/l) in 22% of patients. 78% of patients had some degree of functional VKD indicated by raised (>0.2 AU/ml) PIVKA-II. Six patients (13%) had a prolonged INR, all of whom had raised PIVKA-II and GGT; 4 also had vitamin K(1) <0.33 nmol/l. Three patients (6.5%) had clinically significant VKD characterised by INR >1.5, PIVKA-II >10 AU/ml, and undetectable vitamin K(1).

CONCLUSIONS: Patients with advanced cancer are prone to VKD which, while usually subclinical, may develop to a clinically relevant prolongation of the INR. Serum measurements of vitamin K(1) and PIVKA-II can be used to detect VKD and monitor vitamin K status before an increased risk of bleeding develops.