Dermatoscopy of an angiomatoid spitz nevus.

To date, only 12 cases of angiomatoid Spitz nevus have been characterized in the literature. We present the first case of angiomatoid Spitz nevus in which dermatoscopic findings are described.

Atypical spitzoid melanocytic neoplasms with angiotropism: a potential mechanism of locoregional involvement.

Atypical spitzoid melanocytic neoplasms (ASMN) may prove difficult to distinguish microscopically from melanoma, and their biological behavior may be unpredictable. ASMN may result in regional lymph node (LN) metastases and frequent sentinel lymph node (SLN) deposits. Angiotropism and extravascular migratory metastasis may account for locoregional metastases in melanoma and thus may potentially explain such locoregional involvement in ASMN. Nine ASMN with angiotropism from 2006 to 2010 were studied. Angiotropism was defined as melanocytes closely opposed to the external surfaces of microvascular channels without intravasation. There were 5 women and 4 men aged 6-40 (mean 18.7) years with ASMN involving the head and neck (5), the extremities (3), and the trunk (1), and the lesions ranged in diameters from 3.5 to 10 (mean 6.2) mm. Breslow thicknesses ranged from 0.66 to 5.35 (mean 3.21) mm, 5 lesions Clark level IV and 4 level V, and dermal mitotic rates varied from 1 to 5 (mean 2.4) per square millimeter. Despite follow-up of 6 months or less in 4 subjects, 5 patients showed regional tumor spread based on detection of SLN deposits, local recurrence, or clinical satellite and LN metastases. Four of 5 patients (80%) undergoing SLN biopsy showed nodal positivity with 2 SLN deposits of >6 mm. Among 4 patients not having SLN biopsy, 1 patient developed local LN metastases after 2 years. We report for the first time angiotropism in ASMN and suggest that such angiotropism seems to correlate with and may explain regional tumor spread in this neoplastic system.

Angiomatoid Spitz nevus: a clinicopathological study of six cases and a review of the literature.

Angiomatoid Spitz nevus is a recently described subtype of desmoplastic Spitz nevus. Six cases have been described in the literature thus far. Here, we describe six additional cases of angiomatoid Spitz nevus and provide a review of the literature on this entity. The features of classic angiomatoid Spitz nevus are described in the context of important differential diagnostic considerations, particularly regressed malignant melanoma.

Angiomatoid Spitz nevus: a distinct variant of desmoplastic Spitz nevus with prominent vasculature.

Five cases of a distinctive variant of desmoplastic Spitz nevus are reported. To the best of our knowledge, this tumor has never been described previously. Clinically, it presents itself as a solitary papule on the extremities of young adults. Microscopically, it shows predominance of solitary melanocytes with epithelioid appearance over cell nests. They are embedded in a prominent fibrous stroma with many densely arranged, small blood vessels with plump endothelia not seen in other Spitz nevi. Because of its resemblance to a vascular tumor, the name angiomatoid Spitz nevus is proposed for this lesion. Absence of recurrences or metastases after complete excision in all cases supports the benign nature of the tumor.

Extent of vascularization as a prognostic indicator in thin (< 0.76 mm) malignant melanomas.

Angiogenesis in malignant melanoma (MM) was evaluated by comparing mean vessel number (MVN) in Spitz's nevi (SN), thick and thin MMs that metastasized, and thick and thin MMs with > or = 10-year survival. Vessels were identified with antibodies against factor VIII-related antigen (FVIII) and CD34 in 37 MMs (17 < or = 1.9 mm and 20 > or = 4.0 mm) with > or = 10-year follow-up and 10 SN from children (< or = 9 years old). Fields (x250) with the highest vessel density were counted by independent observers blinded to clinical outcome. There were no differences in MVN between SN versus MMs (P = 1.0), but the distribution of vessels was much more uniform in SN. Seven MM pairs (> or = 5.5 mm) and five pairs (< or = 0.75 mm) were matched by sex, age, site, stage, and primary treatment (paired t-test). In the pairs > or = 5.5 mm, there was no correlation with MVN with either metastasis or death (FVIII P = 0.98; CD34 P = 0.85). Among the thin paired lesions, high MVN (FVIII = 46, CD34 = 39) was significantly related not only to metastasis (FVIII P = 0.04, CD34 P = 0.03) but also to death (FVIII P = 0.04, CD34 P = 0.05). MVN does not separate SN versus MM nor predict outcome in thick (> or = 4.0 mm) MMs; however, high MVN (> or = 42 average) is predictive of metastasis and death in MMs < or = 0.75 mm. Larger matched studies are indicated to confirm this observation.

Comparative analysis of neovascularization in primary cutaneous melanoma and Spitz nevus.

Spitz nevus is a well-known histologic simulator of malignant melanoma. Vascularity of human neoplasms has been associated with prognosis as well as propensity for metastasis. Were vascularity significantly different between melanoma and Spitz nevus, it could serve as a feature to distinguish between these two neoplasms. We evaluated the vascularity of a series of primary cutaneous melanomas ranging from thin superficial spreading to nodular lesions as well as superficial compound and nodular deep Spitz nevi by using light-microscopic evaluation of factor-VIII-stained sections. Vascularity was density graded and microvessels were counted per x200 and x400 field. Vascular density and microvessel counts were significantly different between melanomas of 2+ and 3+ vascularity compared with all types of Spitz nevi. Although nodular malignant melanomata tended to have a greater degree of vascularity than thin melanomas, there was a significant population of both of these subtypes having few or many vessels. We conclude that the number of microvessels per x200 and x400 field in areas of greatest vascularity is significantly less in Spitz nevus than in malignant melanoma. There is a subset of melanoma, however, in which the number of microvessels may be low. Nodular melanomata tended to have a greater number of vessels than did thin superficial spreading lesions. Evaluation of microvessel count may be of assistance when coupled with clinical and histologic findings in distinguishing between melanoma and Spitz nevus in selected cases.