Chay, WY., Tan, SH., Lo, YL, Ong, S.Y., Ng., H.C., Gao, F., . . . Choo, S.P. (2010). Use of calcium and magnesium infusions in prevention of oxaliplatin induced sensory neuropathy. Asia Pacific Journal of Clinical Oncology, 6, 270–277.

The purpose of the study was to evaluate the neuropathy-protective effects of calcium and magnesium infusions in patients receiving oxaliplatin.

Patients were randomized to a treatment group with calcium gluconate 1 g plus 1 g of magnesium sulfate in 100 ml normal saline infused before and after oxaliplatin, or a placebo group with infusions of normal saline.

• The sample consisted of 19 participants with a mean age of 54 years.
• The amount of men (52%) slightly outnumbered the amount of women (48%).
• All of the participants had colorectal cancer and were receiving oxaliplatin-based chemotherapy with a life expectancy of more than three months.
• Exclusion criteria included previous treatment with platinum-based chemotherapy and/or a preexisting neurologic disease or metastases.
• Seventy-eight percent of the patients received 600 mg/m² of oxaliplatin.
• The median follow-up was 8.7 months.

The study was conducted in a single-site location in Singapore.

• Active treatment
• Late effects

The study was a blinded, placebo-controlled, randomized phase II design.

Measurements included the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0] and oxaliplatin-specific toxicity scale nerve conduction studies.

Incidence of grade 1 and 2 neurotoxicity was higher in the placebo group, but there was a higher proportion of grade 3 cumulative numbness in the treatment group. No differences were noted between groups for tingling and cold sensitivity. In addition, no difference was noted in time to onset of symptoms. Conduction studies showed lower median score at the end of the study in the treatment arm (p = 0.02). Of note, the study was ended prematurely.

This study does not provide strong evidence regarding the efficacy of calcium and magnesium infusion for the reduction of chemotherapy-associated peripheral neuropathy.

• A small sample size (less than 30 participants).
• Findings and reported conclusions can be confusing since median end of study nerve conduction scores suggested increased abnormal conduction in the treatment group, as noted by the authors.
• A correlation between nerve conduction findings and subjective patient symptoms are unclear.
• No information was provided regarding chemotherapy treatment delays or dose reductions.
• Given the question of cumulative effects, it may be more useful to look at symptoms at oxaliplatin dose levels rather than time.

Because of a small sample size, this current study does not provide strong evidence regarding use of calcium and magnesium infusions. Neuropathic symptom effects appear to be mixed, with higher prevalence of grade 3 with treatment, but overall prevalence lower with treatment. Some symptoms appear to be affected and some do not, and the relationship between nerve conduction findings and symptoms are unclear. Additional research in this area is needed to clarify the actual impact of calcium and magnesium for protective effects with neurotoxic treatment.