Selenium as Cancer Treatment The use of selenium compounds as a cancer treatment predates most conventional treatments currently in use.91 In spite of this, comparatively little is known regarding the use of selenium as a cancer therapy in living systems. Subcutaneous injection of 2 mcg/g selenium into tumor-bearing mice led to a 75-percent reduction in tumor mass compared to controls.92 This inhibitory effect of selenium was confirmed in human breast cancer cells in vitro.93 In an open trial of 32 patients with treatment refractory brain tumors, intravenous infusion of selenium (1000 mcg/day for 4-8 weeks) was associated with a slight to definite improvement in all participants. Symptomatic decrease was seen in nausea, emesis, headache, vertigo, and seizure activity. Although the results are largely credited to the selenium treatment, it should be noted these patients were concurrently receiving chemotherapy, oxygen therapy, vitamins E and A, dietary changes, and psychotherapy.94 Unpublished research from the 1950s outlines the treatment of over 1000 malignancies with selenium compounds, reportedly with beneficial results.95 Unfortunately, a study of this magnitude has yet to appear in the peer-reviewed literature. Selenium with Radiation Little is known about the interaction between selenium supplementation and radiotherapy. In the one human trial available, patients with advanced rectal cancer were given daily supplementation with 400 mcg of selenium after treatment. The selenium was well-tolerated, but the researchers presented no data regarding interaction between the two treatments.96 An animal study suggests that selenium depletion reduces the lethal dose of radiation.97 Until more is known regarding the effect of selenium on radiotherapy, pharmacological doses (above 400 mcg/day) cannot be advised. Selenium with Chemotherapy Interactions between selenium and platinum-containing chemotherapy agents have been extensively studied. In a mouse study, selenium decreased nephrotoxicity of cisplatin, while simultaneously increasing its anti-tumor activity.15 Other animal studies confirmed these findings.16,98 A randomized crossover trial in humans looked at the effect of selenium (4000 mcg/day from four days before until four days post-chemotherapy) on the toxicity of cisplatin. Selenium consumption was associated with a higher WBC count, even with less consumption of granulocyte stimulating factor. Nephrotoxicity, measured by urine enzymes, was also significantly less in patients taking selenium. No mention is made in this study of any effect of selenium intake on the therapeutic activity of cisplatin.99 One in vitro study suggests a selenium-containing antioxidant compound called Ebselen (2-phenyl-1,3-benzisoselenazol-3(2H)one) has a mild inhibitory effect on the anti-tumor effect of bleomycin. The authors did not speculate on whether dietary selenium would have an adverse effect on therapeutic use of bleomycin.100 Perhaps until these results are followed up, it would be best to avoid this combination. Alternative Medicine Reviews, 1999;4(5):304-329 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.