Selenium supplementation and irinotecan

I was doing some reading and i figured this was worth sharing, besides selenium general anti cancer benefits, the synergy with irinotecan well grabbed my attention and i thought i might as well post it here for some of my friends on chemo irinotecan.

You can read the summary below. I have mentioned these lef guides before, a few of us here follow some aspects of the protocol. if your interested in supplementation for colorectal its as good a place to start as anywhere.

i am not recommending you buy any lef products, but i do use them selectively. i also joined and they send you the lef supplement bible, one of the best references you would ever want to read.

as always ask your onc, if you know more than him, we will likely give you a free consult or maye a movie ticket. then again he may charge you double.

goodluck and enjoy reading the lef protocols if you cannot sleep.


Selenium deficiency has been linked to formation of many cancers, including colorectal cancer (Nelson 2005). Selenium is incorporated into proteins within cells, called “selenoproteins”, involved with protecting the cells from free radical accumulation that can lead to DNA damage. Some of these proteins include glutathione peroxidases (GPx), thioredoxin reductases (TrxR), and selenoprotein P (SePP). People that form adenomas are more likely to be deficient in selenium as well as the selenoproteins that protect DNA from damage. Repletion of selenium through supplementation restored both deficiencies, presumably leading to protection from further adenoma formation (Al-Taie 2003).

There have been a number of studies showing that selenium is lower in those with adenomas or colorectal cancer compared to controls (Mikac-Devic 1992; Ghadirian 2000; Fernández-Bañares 2002). Selenium may afford even more protection in current smokers and those that have quit less than 10 years previously (Peters 2006).

Selenium supplementation at the time of cancer surgery can increase local immune function, an effect which may reduce recurrence (Kiremidjian-Schumacher 2001). There may also be synergistic effects of selenium with other nutrients such as folate (Connelly-Frost 2009).

A clinical trial of 200mcg of selenium versus placebo found that the incidence of colorectal cancer was significantly less in those taking selenium (Clark 1996).

Selenium may also synergize with some cancer treatment drugs (Rudolf 2008). In a phase I clinical trial using high doses of selenomethionine alongside the chemotherapy drug irinotecan, the authors remarked “unexpected responses and disease stabilization were noted in a highly refractory population” (Fakih 2006). Selenium in high amounts can be toxic and evidence suggests that doses in the 200 – 400 mcg range are most beneficial (Reid 2008).