Royal Microscopical Society Microscopy Handbooks

Abstract

mitoses/5 high power fields (= 1 sq mm on Ul{cer our microscopes), presence or absence of ulceration, degree of lymphocytic reaction to tumour, degree of regression, presence of dermal blood vessel/lymphatic invasion, evidence of a pre-existing cellular naevus, and adequacy of excision.These features can be so variable within a given melanoma that we believe that only by blocking the entire lesion in serial blocks can proper assessment be made.In those cases where the basic melanomatous nature of the lesion is uncertain at the time of cut up, not all the lesion is blocked; some is kept back for possible electron microscopy etc.When the melanoma is confirmed the X ^Q v r reserve is then utilised to complete the paraffin section series.Such techniques do not add greatly to our workload, even with the number of new primary cases which we see.