The aim of this work was to evaluate the correlation between the serum levels of lactate dehydrogenase (LDH) and magnesium (Mg) alone or in report Ca/Mg, among patients with diagnosed malignant diseases who were admitted to the oncology department of a county hospital. Results:Among the patients in this study, 55 patients (73%) exhibited normal serum levels of Mg (normal range value = 1.60-2.3 mg/dL; mean value = 2.2 mg/dL; SD = 0.2; p = 0.02), normal values for Ca (range 9.1 -10.8 mg/100 m, mean value = 9.90, SD = 2.5, P = 0.05) and normal report Ca/Mg (range 4.5-7), following cancer therapy with good results, in the stage of remission tumor. A number of 12 patients (16%), which was discovered in onset of cancer diseases, displayed high levels of serum Mg (range =2.6-3.27 mg/dL; mean value = 2.89 mg/dL), high values of Ca, (mean value = 11.2 mg/dl), and low values of report Ca/Mg ( range = 1.7- 3.8). Six patients (8%), with bad prognostic, unfavorable cancer therapy and frequent relapses, exhibited low levels of Mg (range = 0.60-1.50 mg/dl; mean value = 1.05 mg/dL), low values of Ca (8.2-8.8 mg/dl) but high report Ca/Mg (range = 8.3-23.5). High Ca/Mg ratio was also significantly associated with high-grade cancer. The levels of serum lactic dehydrogenase (LDH) were also evaluated in patients newly diagnosed with cancer and in patients with unfavorable responses to the cancer therapy (range = 240-1330 U/L; mean value = 787 U/L; SD =1.33; p = 0.002; normal values 135-225 U/L). Conclusion: The total serum LDH, Mg and report Ca/Mg levels can be used as markers for the onset of malignant diseases and for monitoring the response to cancer therapy.
