Propecia use after surgery to remove gynecomastia? (Photo)

Hi, I am a 31 year old male who had surgery 6 months ago to remove gynecomastia that occurred in puberty. I had great results from this procedures but now I'm faced with hair thinning which I noticed a couple months ago. I went to a dermatologist who recommend I use propecia 1mg, however, I learned that one of the side effects are gynecomastia. Am I at a higher risk than others because I had gynecomastia before? Or am I at less of a risk since majority of the gland was removed?