Melanoma in Situ

Hi, today, after an 11 week wait, I received the results from a skin biopsy I had done on a mole behind my ear.

The diagnosis was as follows
"at least superficial spreading melanoma in situ with dermal regression including chronic inflammation and melanophages to a depth of 0.4mm. Lesion is 2mm clear of nearest peripheral margin"

The gross description included "SE measuring 20x11x5mm with a central flat dark brown lesion measuring 10x7mm"

I had overheard the junior doctor talking with a senior doctor/consultant outside before they came in and they were mentioning the 0.4mm and they had discussed it before Xmas but there was some confusion. My main oral & maxillofacial consultant then came in and told me it was a strange one and the report was saying melanoma in situ. I have an appointment again in 4 weeks but may be back sooner if they need to take more skin, I believe the MDT are meeting on Friday week.

My question is, does the diagnosis seem strange that it would confuse the team, is there something not matching up.

Also, what are the chances that I could have other melanoma in situ in other areas of my body once I have one?

Any advice, experience is appreciated.

Thanks.