Discerning Atypical Mole Pathology report

I had my first "body check" with a new dermatologist recently. She came very highly recommended. After looking me over, there was one small spot on my arm that she was concerned about  and she removed it for a biopsy. A week later she called to say that it was an atypical mole and that it was NOT a melanoma but that the recommendation was to remove more tissue around the area and that it would leave a scar about an inch long. I had done some homework and so I asked if this mole was mild, moderate, or severely dysplastic which seem to be the common terms used in grading atypical moles. She said that the lab she uses does not use those terms. She said the mole was "beyond atypical"; that several  dermatological pathologists viewd the pathology on this mole and that all recommended additional removal. I'm a little annoyed that these doctors are not using the common language/terms regarding atypical mole pathology and can't help but wonder if this is  a way to generate more business for the doctor's practice. Should I allow the Dr. to "clear the margins" or get a second opinion? I think it's important to say, I  have a brother who has had several melanomas removed.