The size of the margin is an important issue in areas that are functionally important (i.e., large vessels like the aorta or vital organs) or in areas for which the extent of surgery is minimized due to aesthetic concerns (i.e., melanoma of the face or squamous cell carcinoma of the penis).
The size of the margin plays a crucial role in regions that are functionally vital, such as large blood vessels like the aorta or essential organs. In addition, it's also important in areas where surgical procedures can be minimized due to aesthetic reasons, like skin cancer on the face or penile squamous cell carcinoma.