Fig. c6t3P1: This was a large (2 cms) tumor of the thigh of a child. It is loosely cellular at this level; the lesion had been treated with topical medications (possibly podophyllin). There is scarring with loose infiltrates of lymphoid cells. Vessels are ectatic.
Fig. c6t3P2: In this field, the neoplastic cells are plump and spindle shaped. They are loosely attached to their neighbors in the fascicles. Nuclei have “heavy” membranes, and nucleoli are prominent. Vessels are ectatic. One fascicle rains down from the epidermis. There are spotty lymphoid infiltrates.
Fig. c6t3P3: In the deeper portion of the lesion, the cells form closely spaced nests and fascicles. There is cellular pleomorphism with numerous epithelioid (rounded) tumor giant cells. Atypia is marked. There is a faint lavender quality to the cytoplasm of the neoplastic cells (the stain had deteriorated by the time the section was photographed; all these transparencies are old). The lesion has tumoral qualities. The adjacent dermis shows areas of scarring.
Fig. c6t3P4: This field is marvelous. An atypical mitotic figure is represented. Cytologic features are atypical and pleomorphic; there are occasional giant cells, some of which are multinucleated. Cells are loosely attached to their neighbors.
Note: The degree of atypia in this case might prompt an observer to simply classify the lesion as a common melanoma. “Spitz-like qualities are represented. The lesion had produced a metastasis in regional lymph nodes.
Fig. c6t3P5: With a Verhoeff-van Giesen stain, the stroma of the tumor is relatively free of elastica.
Fig. c6t3P6: At the advancing margin, where nests of neoplastic cells, and individual neoplastic cells have infiltrated the dermis, the elastica of the reticular dermis is preserved. The presentation of this case is continued in the next chapter (fig. c7t3P1).
