Hi there
It must be awful to have the threat of these things hanging over you. I guess most people who have ahd melanoma once also feel that way but a lot of them have the spreading and deeper invasion to take their minds off a second primary - the first primary is their main worry if you like.
It's brilliant that you are continuing to have checks and hopefully anything else that does pop up will be caught in situ as well - which does confer a highly unlikely chance of spread and as you must be aware, 99% survival/cure rate.
I can only imagine how horrid it must be to have one after another come up. I would be feeling scared and unlucky too...I'm not a patient, my best friend is, and I have never had melanoma - yet - so I am extremely lucky compared to you. There's no use in anyone getting competitive about this stuff
I think yes, your chances of having more primaries are higher than people who have never had a melanoma, but I have heard stories of people going on for years and years without anything progressing further than an 'in situ' stage, and just having them chopped out when they appear.
This is definitely the best course of action for you at this stage, and I wish you every success in dealing with any more that come along.
Take care
Lucy