My interpretation:
1. “This abuts the prostate margin...” means the 7mm lesion is next to the prostate outer edge (google 'capsule').
Of course, you want to know how much of the 7mm lesion is next to the edge...
2. "...over 6mm."

If the lesion had extended outside the prostate, I'd expect the MRI report to identify it as extraprostatic extension.

Hopefully an expert will chime in and confirm my interpretation.