The atypical Spitz tumor of uncertain biologic potential

A series of 67 patients from a single institution

Authors

  • Mathew W. Ludgate MBChB,

    Corresponding author
    1. Department of Dermatology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
    • Department of Dermatology, University of Michigan Medical School, 1618 A. Alfred Taubman Healthcare Center, 1500 E Medical Center Dr, Ann Arbor, MI 48109
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    • Fax: (734) 936-6395

  • Douglas R. Fullen MD,

    1. Department of Dermatology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
    2. Department of Pathology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • Julia Lee MPH, MS,

    1. Department of Statistics, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • Lori Lowe MD,

    1. Department of Dermatology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
    2. Department of Pathology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • Carol Bradford MD,

    1. Department of Otolaryngology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • James Geiger MD,

    1. Department of Surgery, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • Jennifer Schwartz MD,

    1. Department of Dermatology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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  • Timothy M. Johnson MD

    1. Department of Dermatology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
    2. Department of Otolaryngology, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
    3. Department of Surgery, University of Michigan Medical School and Comprehensive Cancer Center, Ann Arbor, Michigan
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Abstract

BACKGROUND:

Atypical Spitz tumors (AST) are rare spitzoid melanocytic proliferations with an uncertain malignant potential. ASTs have overlapping features of both Spitz nevi and spitzoid melanoma, and consequently generate controversy with diagnosis and management. Sentinel lymph node biopsy (SLNB) has been proposed as a possible means to gain additional insight into the true biologic potential of these tumors; however, previous reports on the use of SLNB in ASTs have been limited by small numbers of patients and short durations of follow-up.

METHODS:

The authors extracted data from their institution's prospective melanoma database, collected between 1994 and 2007, for all patients with ASTs of uncertain biologic potential. They reviewed the clinical features of these patients, including the sentinel lymph node status, and the histological features of the tumors.

RESULTS:

A total of 67 patients with ASTs were identified, with a median age of 23.7 years. The mean depth was 2.4 mm. Of these, 57 had a SLNB performed, with 27 (47%) having a positive sentinel lymph node. SLNB-positive cases had a significantly lower mean age than SLNB-negative cases (17.9 vs 28.7 years; P = .013); however, no other significant differences were observed. All 27 patients with a positive SLNB were alive and disease free with median follow-up of 43.8 months. One patient who did not receive a SLNB developed recurrent disease with regional and distant metastases.

CONCLUSIONS:

ASTs do not appear to behave like conventional melanoma. There is a high incidence of microscopic lymph node deposits in SLNBs, but despite this finding, patients have a favorable prognosis. Our findings raise several questions regarding the malignant potential of ASTs, and the role of SLNB in their management. Cancer 2009. © 2009 American Cancer Society.

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