I had a spot about the size of a small fingernail on my scalp, and after finding info on ACV, hydrogen peroxide, and baking soda, I made a paste of the three together and applied it to the area and covered that with a band-aid. Within a few days, I noticed the area became covered with a soft sticky yellowish scab-like material (called slough...it's normal). I did try carefully to wipe that off, but realized it is actually part of the tissue, so I continued applying the paste, and eventually the area became covered with a dark, almost blackened scab-like material. What I realize now, or at least what I think was/is happening, is that the paste is getting down into the cancer cells and they start to die off, so the area is going to look rough for a while. Obviously the paste is doing it's job though. I'd stopped applying it now and then, for a day or two, to see what I could see, and it became obvious that it was working. I could see the skin around the are beginning to draw in as healing was starting. One time, because I thought I saw an bit of odd discoloration along one outer area, I reapplied the paste-mixture and covered that too, just to be safe and to be sure I got to the very roots of the cancer cells. I reapplied the paste each day, maybe twice if I could, and let it do its work, and now I'm pretty sure the discoloration was a bad area because the paste got down into that area too and it repeated the above process.
To be frank, I maintained this for 30+ days (though the entire experience was 2-3 months worth) and I think it was all worth it as an alternative to having surgery and a big scar on my head. I took ongoing pictures of the area and created a simple video to show the progress. Yes, it seems like a long time in hindsight, but eventually the area began to fully heal and no more questionable areas were to be seen. The doctor (to his great surprise :) rechecked the area and told me no more sign of BCC. Now I only have a small spot where all this went on, but it healed over with natural skin tones and the scar isn't significant (considering all the little dents and dings we have on our heads by the time you're my age)!
So, to me, the ACV is what I think is the strongest factor, and the ACV, Hydrogen peroxide, baking soda mixture is the most powerful paste imho. I also use a Hydrogen peroxide & baking soda-only mixture if I want to apply a less aggressive mix to anything that looks vaguely suspicious. And I drink an occasional teaspoon of ACV in water, since I've read that can help too.
(My disclaimer: this worked for me, ymmv, and definitely check with your doctor. If it had been anywhere else on my body I might have accepted the suggested Mohs surgery and been done with it instantly...but I still keep the above paste/mixtures handy.)
