Q: I have a bit of squamous cell skin cancer on my face. Iâm hoping that black salve will knock it out without my having to have surgery or radiation. My wife says I have to ask you first. So? â Hank F., Livingston, N.J. A: Smart woman, your wife. Black salve is dangerous. While sellers claim it kills skin cancer cells and leaves healthy cells untouched, it actually erodes your skin, causing permanent scarring and disfigurement, often triggers serious infection and leaves cancer cells deep in the skin untouched. The Food and Drug Administration recently issued an alert saying that i...