Nevus spitz D22.-

Mostly solitary (isolated reports of multiple occurrences), sharply circumscribed, 0.5 mm to 2.0 cm in size, hemispherically protuberant, round or oval, with a smooth shiny surface, light brown-reddish to blue-black nodule (or papule) interspersed with telangiectasias. The consistency is elastic to coarse.

Diascopic: Yellowish-brownish intrinsic infiltrate. Typical indication of rapid growth (within a few weeks!).

Reflected light microscopy: Characteristic reflected light features of Spitz nevi include zonular, cocard-like, or radial-striated basal architectures, annular or centrolesionally arranged areas of gray-black centropapillary globules or brown/black dots, scattered or ring-like peripheral gray-blue pseudopodia, perivasal melanophages, and inverse reticular patterns, especially in epithelioid cell nevi. In contrast to malignant melanomas, vascular polymorphisms, except in desmoplastic Spitz nevus, aneurysmal vascular outpouchings, and severe caliber variations as well as microscopic blood lakes are extremely rare. In some cases, perivasal melanophage agglomerates and bluish-gray pigment rings appear as internal mesh boundaries.

• Melanocytic nevus with 3 developmental phases (as with other melanocytic nevi):
  • Naevus Spitz - Junction type
  • Naevus Spitz - Compound type
  • Naevus Spitz - dermal type.
• Tumours are usually symmetrical and sharply defined. Hyperplastic epidermis with orthokeratosis, hyperkeratosis, hypergranulose and acanthosis. Typical cleavage between melanocyte nests and surrounding keratinocytes. Cell polymorphies, mitoses and fish-like vertebrae of spindle cells are visible. Also epithelioid melanocytes with broad, homogeneous, eosinophilic cytoplasm are not rare. Multinucleated giant cells may occur. Mostly low pigmentation, but in individual cases massive. No destruction of the collagen fibres. Mitoses are found in the upper parts of the tumour, but not in the depth (important distinguishing feature from malignant melanoma). A typical feature are homogeneous, PAS-positive, light red globules (according to the first descriptor: kamino-bodies). The most important phenomenon of the Spitz nevus in demarcation to the malignant melanoma is the maturation of the melanocytes towards depth (as with other melanocytic nevi).
• Histological variants:
  • Pigmented spindle cell nevus (reed): Here a uniform, strongly pigmented, spindle cell race predominates.
  • Pigmented epithelioid cell nevus: Composed of nests of highly pigmented, large epithelioid cells.
  • Granulomatous Spitz nevus: Predominantly dermal type. When magnified, the examiner is reminded of a sarcoid reaction.
  • Plexiform Spitz nevus: Plexiform arrangement of predominantly spindle and epithelioid melanocytes.
  • Desmoplastic Spitz nevus: Variant of a dermal Spitz nevus in which usually a few epithelioid melanocyte nests are located in a fibrosed dermis with broad, tangled collagenous fibre strands.

Malignant melanoma; tuberculosis cutis luposa; lymphadenosis cutis benigna; juvenile xanthogranuloma; dermatofibroma; pigmented spindle cell tumor.

Excision in healthy individuals without a safety margin.

The pigmented spindle cell nevus (reed) is considered a variant of the Spitz nevus. The diagnosis of Spitz nevus in adults must be evaluated with a critical distance. In case of doubt this histological evaluation is to be classified as malignant.

1. Ackerman AB, Maize JC (1987) Pigmented lesions of the skin. Lea & Febiger, Philadelphia
2. Ackerman AB (1990) A dermatopathologist`s guide to melanocytic nevi and malignant melanomas. In: Conley I (ed) Melanoma of the head and neck. Thieme, Stuttgart New York, pp 9-33
3. Borsa S et al (1991) Bubble-cell variant of the Spitz nevus. Dermatologist 42: 707-708
4. Clarke B et al (2002) Plexiform acute nevus. Int J Surg Pathol 10: 69-73
5. Gartmann H et al (1985) The Spitz nevus - A clinical and histological analysis of 652 tumours. Z Hautkr 60: 22-42
6. Hoang MP (2003) Myxoid Spitz nevus. J Cutan catholic 30: 566-568
7. Reynolds N et al (2003) Nodal Metastatic Melanoma in the Neck of a 4-years old girl after diagnosis of Spitz nevus of the cheek. Ann Plast Surgery 50: 555-557
8. Schulz H (1996) Differential diagnosis of Spitznaevi. Microscopic differentiation from malignant melanomas. TW Dermatol 26: 331-335
9. Spitz S (1948) Melanomas of childhood. Am J Pathol 24: 591-602
10. Zaenglein AL et al (2002) Congenital Spitz nevus clinically mimicking melanoma. J Am Acad Dermatol 47: 441-444