Skin - Melanocytic tumor
Nevi
Atypical Spitz nevus

Author: Christopher Hale, M.D. (see Authors page)

Revised: 27 February 2017, last major update March 2013

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Atypical Spitz nevus

See also: Spitz nevus
Cite this page: Atypical Spitz nevus. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/skintumormelanocyticatypicalspitz.html. Accessed December 13th, 2017.
Definition / general
  • Junctional or compound lesion not fulfilling the histopathologic criteria of melanoma but with one of the following features:
    • Asymmetry
    • Predominance of single melanocytes over nests in lesions 4 mm or larger
    • Ulceration
    • Large dermal sheets of melanocytes
    • Lack of maturation in dermis
    • Deep dermal mitotic figures
    • Extensive involvement of subcutis
    • Nuclear pleomorphism (Mod Pathol 2006;19:S21)
Terminology
  • Also called Spitz tumor with one or more atypical features
Epidemiology
  • Mostly young patients
Clinical features
  • Regional lymph node involvement in up to 1/3 (Hum Pathol 2006;37:816)
  • Usually large and deep with pushing borders into dermis and subcutis
Case reports
Treatment
Microscopic (histologic) description
  • Junctional or compound lesion not fulfilling the histopathologic criteria of melanoma but with one of the following features:
    • Asymmetry
    • Predominance of single melanocytes over nests in lesions 4 mm or larger
    • Ulceration
    • Large dermal sheets of melanocytes
    • Lack of maturation in dermis
    • Deep dermal mitotic figures
    • Extensive involvement of subcutis
    • Nuclear pleomorphism (Arch Dermatol 2005;141:1381, Cancer 2003;97:499)
Microscopic (histologic) images

Images hosted on PathOut server:

AFIP images:

Large epithelioid cells with amphophilic cytoplasm
are characteristic of Spitz nevi and the nuclear atypia
observed here should not suggest melanoma in the
absence of other features



Images hosted on other servers:

Various images

Thigh

Various images

Asymmetry but highly cohesive nests


Buttock tumor:

Multinucleated tumor cells

Sheets of atypical tumor cells with frequent mitotic figures

Somewhat symmetric

Large nests of atypical tumor cells

Positive stains
Molecular / cytogenetics description
Differential diagnosis