From the PubMed site, an in vitro study from 2010:
Colloidal silver had dose-dependent cytotoxic effect in MCF-7 breast cancer cells through induction of apoptosis … The present results showed that colloidal silver might be a potential alternative agent for human breast cancer therapy.
Other studies looking at both breast cancer cells and colon cancer cells have compared silver’s antitumor properties to that of the chemotherapy drug Cisplatin, and found it more effective without the side-effects.
Even though the last ten years have shown vast improvement in cancer outcomes, with far fewer people dying, treatments for cancer are still known for being harsh and difficult to endure.
Since the study came out in 2010, other studies have come out showing the safety of colloidal silver. That it doesn’t stay in the body, harm organs, or any of the other concerns that opponents of colloidal silver have raised over the years.
One of the benefits of silver is that because it doesn’t have harsh side-effects (you just need to replenish your good bacteria with some yogurt or other probiotic), and it has no known interaction with other drugs, it could also be a potential complementary treatment, helping people to fight cancer faster and more effectively.
What do you think of silver’s potential for fighting tumors?