Okun, Edelstein, and Fisher

 
"Microscopic features (superficial spreading melanoma in situ)
 
  1. The epidermis is generally normal in thickness or acanthotic.
  2. Tumor cells tend to be cuboidal or pagetoid and tend to show significant upward invasion of the epidermis. Nuclear pleomorphism may be pronounced. Cytoplasm may be very abundant, and "dust-like" melanin is often seen.
  3. A lymphoid cell infiltrate intermingled with melanophages is often present in the upper dermis, but solar damage is usually not prominent, since lesions are not dependent on solar damage."
 
Okun MR, Edelstein LM, Fisher BK. Gross and microscopic pathology of the skin. 2nd Edition. Canton: Dermpath Foundation Press, Inc., 1988:1194.
 

Brief Critique

 
Apart from reference to "dust-like" melanin in neoplastic pagetoid cells, nothing alluded to enables differentiation of melanoma from some examples of Spitz's nevus.