Thiamine deficiency in patients with B-chronic lymphocytic leukaemia: a pilot study

Malignancy associated primary thiamine deficiency has been documented in se veral experimental tumours, sporadic clinical case reports, and in a number of patients with fast growing haematological malignancies. Thiamine status was assessed prospectively in 14 untreated B-chronic lympho cytic leukaemia (CLL) patients, and in 14 age matched control patients with nonmalignant disease. Patients with any known cause of absolute, relative, or functional thiamine deficiency were excluded. High (>15%) thiamine pyrophosphate effect (TPPE), indicating thiamine defic iency, was found in five out of 14 CLL patients (35.7%) and in none of the controls (p=0.057). Mean (SD) TPPE in the thiamine deficient patients group was 21.6 (3.4)%. In all the patients, thiamine deficiency was subclinical. No correlates for the thiamine deficiency have been found save for an incr ement of more than 20% in the total leucocyte count over the preceding thre e months, which was found in all five thiamine deficient patients compared with only one of the nine nonthiamine deficient CLL patients. Thus, CLL patients may be prone to develop primary thiamine deficiency poss ibly promoted by the increased leucocytes span, which may increase thiamine consumption. Since even subclinical thiamine deficiency may be detrimental to the patient's clinical course, and in view of the theoretical danger of thiamine promoted tumour cell proliferation, further large scale studies a re warranted to confirm this observation, and to elucidate the issue of thi amine supplementation to CLL patients.