I'd recommend having it looked at by a dermatologist if you haven't already. I had a weird red lesion on my back that I thought was either from an acne cyst or a bug bite, but then a few years later the thought, "what is this? Could this be a melanoma based on the whole 'ugly ducking' method they talk about" hit me and sent me into a panic I haven't recovered from. I'm terrified to get it checked out. Had I gone in right away, I would have probably been fine either way.
Over the years, I've mostly scoffed at all the various "X causes acne" claims....but this one is too clear for me to ignore. I have noticed in recent years that when I go long periods of time without eating anything that was microwaved, my acne is far more mild. And then when I resume eating microwaved food, it flares up. Has anyone else ever noticed a link?