No association between lithium therapy and leukemia

Failure of lithium to reduce period of neutropenia during induction therapy of acute myeloid leukemia

Fifty-four patients treated with daunorubicin, cytosine arabinoside and thioquanine for acute myeloid leukemia were randomly assigned to receive oral lithium carbonate 1200 mg daily or no lithium. The duration of neutropenia (less than 0.5 x 10(9)/L) was similar between controls (median 22.5 days) and patients treated with lithium (median 24 days). The number of remissions, relapse-free survival and survival were similar for the lithium treated and control groups of patients. There was no apparent clinical efficacy in the use of lithium to reduce the period of neutropenia in patients undergoing remission induction therapy for acute myeloid leukemia.

Lithium and immune function

Lithium has potent antiviral and immunostimulating properties which are probably consequences of its actions on prostaglandin synthesis. Although lithium has considerable potential in the prophylaxis of some viral illnesses and other manifestations of defective immune function, it is, paradoxically, capable of activating autoimmune mechanisms in predisposed patients.

Cancer risk from inorganics

Inorganic metals and minerals for which there is evidence of carcinogenicity are identified. The risk of cancer from contact with them in the work place, the general environment, and under conditions of clinical (medical) exposure is discussed. The evidence indicates that minerals and metals most often influence cancer development through their action as cocarcinogens. The relationship between the physical form of mineral fibers, smoking and carcinogenic risk is emphasized. Metals are categorized as established (As, Be, Cr, Ni), suspected (Cd, Pb) and possible carcinogens (Table 6), based on the existing in vitro, animal experimental and human epidemiological data. Cancer risk and possible modes of action of elements in each class are discussed. Views on mechanisms that may be responsible for the carcinogenicity of metals are updated and analysed. Some specific examples of cancer risks associated with the clinical use of potentially carcinogenic metals and from radioactive pharmaceuticals used in therapy and diagnosis are presented. Questions are raised as to the effectiveness of conventional dosimetry in accurately measuring risk from radiopharmaceuticals.