A presentation on May 15, 2008 at the 44th annual meeting of the American Society of Clinical Oncology revealed that calcium and magnesium administered intravenously to patients undergoing chemotherapy results in a significant reduction in neurotoxicity, a common side effect of chemotherapeutic drugs. The condition is characterized by pain in the extremities that can be severe enough to prevent cancer patients from continuing their treatment.
Researchers with the North Central Cancer Treatment Group administered intravenous calcium and magnesium before and after treatment with the chemotherapeutic drug oxaliplatin to 50 of 102 patients with advanced colon cancer. The remaining 52 patients received oxaliplatin with an intravenous placebo. The research team found a significant reduction in neurotoxicity incidence, severity, and time to onset associated with the use of calcium and magnesium compared with the placebo group.
"We designed a double-blind, placebo-controlled study that confirmed the effectiveness of calcium plus magnesium in reducing debilitating neurological sensitivity associated with oxaliplatin, such as pain in the hands, fingers, feet and toes," explained study co-chair Daniel Nikcevich, MD, PhD, who is an oncologist at St. Mary's Duluth Clinic in Minnesota. "In the past, these side effects have caused patients to stop treatment and, therefore, not receive critical therapy."
"Some initial reports from other studies claimed that the use of calcium and magnesium reduced the activity of oxaliplatin-based chemotherapy," added co-chair Axel Grothey, MD of the Mayo Clinic. "However, we have definitive results from an independent, blinded radiologic review which demonstrates no negative influence of calcium and magnesium on the outcome for oxaliplatin-based chemotherapy."
"Now that we have shown the effectiveness of calcium and magnesium in reducing oxaliplatin-induced neurotoxicity, a further step may be to evaluate the benefit of calcium and magnesium in reducing neurotoxicity caused by other medications," Dr Nikcevich stated. "Many other commonly used chemotherapy agents cause neurological sensitivity. By applying our study design, we can test the effectiveness of calcium and magnesium when used with other treatments."
Related Health Concern: Cancer chemotherapy
Cancer chemotherapy is known to produce severe side effects such as heart muscle damage, gastrointestinal damage, anemia, nausea, and lethal suppression of immune function.
Nutrients and hormone therapies can be used to mitigate the toxicity of chemotherapy. Bolstering the immune system may help alleviate or reduce the severity of the complications associated with chemotherapy.
Melatonin has been shown to protect against chemotherapy-induced immunosuppression. Melatonin mediates the toxicity of chemotherapy and inhibits free-radical production (Lissoni et al. 1999). In a randomized study to evaluate the effect of melatonin on the toxicity of chemotherapy drugs, patients receiving melatonin with chemotherapy had lower incidences of neuropathies, thrombocytopenia, stomatitis, alopecia, malaise, and vomiting. The appropriate dose of melatonin was between 30-50 mg at bedtime (Lissoni et al. 1997a; Lissoni et al. 1997b). Adding melatonin to a chemotherapy regimen may prevent some toxic effects of the chemotherapy drugs, especially myelosuppression (suppression of blood cells production in bone marrow) and neuropathies (abnormality of nerve functioning both within and outside the central nervous system).
Melatonin may also be an especially effective and safe therapy to correct thrombocytopenia, a condition characterized by a decrease in the number of blood platelets. In patients who randomly received chemotherapy alone or chemotherapy plus melatonin (20 mg each evening), thrombocytopenia was significantly less frequent in patients treated with melatonin (Lissoni 2002). Malaise and lack of strength were also significantly less frequent in patients receiving melatonin. Finally, stomatitis (inflammation of the mouth area) and neuropathy were less frequent in the melatonin group.