In situ Melanoma Excision

I recently had an in-situ melanoma (SSM) excised from my chest (after an initial biopsy--which was a scrape).  Apparently there was melanoma present in the excised tissue that was less than 2.5 mm from the border of healthy tissue. So to be totally safe, I have to have the procedure done over again. Why/how does this happen? I'm uncomfortable asking the Doctor directly if this is his error. Should I consider another having another dermatologist do the second excision?

[Alan Rockoff, MD]

No, it's not an error.  When the whole of a lesion is removed, the pathologist gets to see parts that weren't included in the original biopsy.  Sometimes these parts show that somewhat more was going on than the original biopsy found--in this case a frank melanoma, which requires more normal tissue removal for precaution's sake.  So it sounds as though you're in good hands.

Best.

Dr. Rockoff