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

Effect of lithium on chemotherapy-induced neutropenia in Egyptian breast cancer patients; a prospective clinical study

PURPOSE

Myelosuppressive chemotherapy-induced neutropenia (CIN) remains a major limitation of cancer treatment efficacy, necessitating very expensive supportive care. Lithium carbonate, an inexpensive drug, can increase the number of neutrophils, possibly providing an efficacious and cost-effective alternative for treating CIN. The aim of this study was to determine whether lithium therapy can attenuate chemotherapy-induced neutropenia and leukopenia in breast cancer patients.

METHODS

A total of 50 breast cancer patients were enrolled in this prospective, interventional, randomized, controlled, and single-blind study. The patients were divided into two groups: a control group (group 1, N = 25 patients) and a lithium-treated (treatment) group (group 2, N = 25 patients). Group 1 patients were further subclassified into a non-neutropenic control group (N = 16) and a neutropenic control (N = 9) based on the subsequent development of severe neutropenia, or not. The control group received 4 cycles of doxorubicin or epirubicin plus cyclophosphamide followed by 2 cycles of paclitaxel. The treatment group received the same regimen as the control group as well as oral lithium carbonate throughout the chemotherapy cycles.

RESULTS

The results showed that the absolute neutrophil count (ANC) was increased in the lithium-treated group, while it was markedly reduced in both the non-neutropenic and neutropenic control groups (by 55.56% and 65.42% post-4 chemotherapy cycles, and by 19.57% and 39.90% post-6 cycles, respectively). The same pattern of alterations was observed for the total white blood cell count in both the control and treatment groups. In addition, the incidence and period prevalence were greatly reduced in the lithium-treated group compared to non-neutropenic and neutropenic control groups.

CONCLUSION

Lithium therapy ameliorated chemotherapy-induced leukopenia and neutropenia in breast cancer patients. This may provide a new strategy for cost-effective treatment of CIN, particularly in Egyptian cancer patients.

Lithium in Cancer Therapy: Friend or Foe?

Lithium, a trace element important for fetal health and development, is considered a metal drug with a well-established clinical regime, economical production process, and a mature storage system. Several studies have shown that lithium affects tumor development by regulating inositol monophosphate (IMPase) and glycogen synthase kinase-3 (GSK-3). Lithium can also promote proliferation and programmed cell death (PCD) in tumor cells through a number of new targets, such as the nuclear receptor NR4A1 and Hedgehog-Gli. Lithium may increase cancer treatment efficacy while reducing side effects, suggesting that it can be used as an adjunctive therapy. In this review, we summarize the effects of lithium on tumor progression and discuss the underlying mechanisms. Additionally, we discuss lithium's limitations in antitumor clinical applications, including its narrow therapeutic window and potential pro-cancer effects on the tumor immune system.

Review of lithium effects on brain and blood

Clinicians have long used lithium to treat manic depression. They have also observed that lithium causes granulocytosis and lymphopenia while it enhances immunological activities of monocytes and lymphocytes. In fact, clinicians have long used lithium to treat granulocytopenia resulting from radiation and chemotherapy, to boost immunoglobulins after vaccination, and to enhance natural killer activity. Recent studies revealed a mechanism that ties together these disparate effects of lithium. Lithium acts through multiple pathways to inhibit glycogen synthetase kinase-3beta (GSK3 beta). This enzyme phosphorylates and inhibits nuclear factors that turn on cell growth and protection programs, including the nuclear factor of activated T cells (NFAT) and WNT/beta-catenin. In animals, lithium upregulates neurotrophins, including brain-derived neurotrophic factor (BDNF), nerve growth factor, neurotrophin-3 (NT3), as well as receptors to these growth factors in brain. Lithium also stimulates proliferation of stem cells, including bone marrow and neural stem cells in the subventricular zone, striatum, and forebrain. The stimulation of endogenous neural stem cells may explain why lithium increases brain cell density and volume in patients with bipolar disorders. Lithium also increases brain concentrations of the neuronal markers n-acetyl-aspartate and myoinositol. Lithium also remarkably protects neurons against glutamate, seizures, and apoptosis due to a wide variety of neurotoxins. The effective dose range for lithium is 0.6-1.0 mM in serum and >1.5 mM may be toxic. Serum lithium levels of 1.5-2.0 mM may have mild and reversible toxic effects on kidney, liver, heart, and glands. Serum levels of >2 mM may be associated with neurological symptoms, including cerebellar dysfunction. Prolonged lithium intoxication >2 mM can cause permanent brain damage. Lithium has low mutagenic and carcinogenic risk. Lithium is still the most effective therapy for depression. It "cures" a third of the patients with manic depression, improves the lives of about a third, and is ineffective in about a third. Recent studies suggest that some anticonvulsants (i.e., valproate, carbamapazine, and lamotrigene) may be useful in patients that do not respond to lithium. Lithium has been reported to be beneficial in animal models of brain injury, stroke, Alzheimer's, Huntington's, and Parkinson's diseases, amyotrophic lateral sclerosis (ALS), spinal cord injury, and other conditions. Clinical trials assessing the effects of lithium are under way. A recent clinical trial suggests that lithium stops the progression of ALS.

Post consolidation therapy for adult patients with acute myeloid leukaemia

One hundred and sixteen adult patients aged 14-73 with previously untreated acute myeloid leukaemia received induction and consolidation chemotherapy with daunorubicin, cytosine arabinoside and thioguanine. Two novel approaches to post consolidation therapy have been investigated. Patients aged 50 years or less who had no suitable matched allogeneic donor were considered for autologous bone marrow transplantation (BMT) using bone marrow which had been cultured in vitro for 14 d. Patients over the age of 50 years with normal bone marrow cellularity and peripheral blood count were treated with a single oral dose of busulphan 100 mg/m2 (without BMT rescue) 3 months following the completion of consolidation therapy. Eighty-seven patients (75%) achieved a complete remission. Of 70 patients who completed consolidation therapy, 40 were aged less than or equal to 50 years and 30 were greater than 50 years. Forty-three patients went on to receive post consolidation therapy in first CR (autologous BMT 12, allogeneic BMT 7, busulphan therapy 24). The event-free survival at 4 years was 47% for autologous BMT, 34% for allogeneic BMT and 45% for busulphan-treated patients. The survival for the older cohort of patients who received post consolidation therapy with single dose busulphan therapy was encouraging, and this agent should be considered for future post consolidation strategies.

Leukemia in bipolar mood disorder: is lithium contraindicated?

The ability of lithium to cause leukocytosis has led to concern that it may also stimulate leukemic cells and hence cause the development of leukemia. This concern has mostly been associated with anecdotal case reports and in vitro studies. In contrast, epidemiology studies and in vivo data fail to affirm this concern. Overall, there is not enough information linking lithium to leukemic development to substantiate such an association.