CD34-positive cellular blue nevi


  • The opinions or assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the Department of the Army, the Department of the Navy, or the Department of Defense.

Kathleen J. Smith COL, MC USA, Departments of Dermatology and Pathology, National Naval Medical Center, 8901 Wisconsin Avenue, Bethesda, Maryland 20089-5600, USA
Tel: +1 301 295 4571/4551
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Background: Although cellular blue nevi (CBN) are well known and characterized, the histopathologic and clinical spectrum of these tumors continues to evolve. We report four CBN with a distinctive histologic and immunohistochemical pattern.

Methods: The histologic features and immunohistochemical staining for S-100 protein, HMB-45, Bcl-2 and CD34 of four CBN with distinctive features were evaluated using routine methods and compared to common CBN.

Results: All four of these distinctive CBN where known to be congenital, and all showed aggregates of plump spindled cells with round to oval nuclei in aggregates and more slender spindled cells with thin wavy nuclei. The slender, spindled cells showed an infiltrative pattern laterally into the dermis and deep into the subcutaneous fat. All four tumors showed diffuse expression of an immunohistochemical stain for CD34, as well as for S-100 protein, Bcl-2, and HMB-45.

Conclusion: Positive immunohistochemical staining with the progenitor marker CD34 defines a subset of CBN. These tumors appear to fit within the spectrum of neurocristic cutaneous hamartomas and may arise from more primitive neurocristically derived cells. Further follow-up of these tumors will be necessary to determine whether this subset of CBN defines a subset with a characteristic biologic behavior.