多发性Spitz痣一例

患儿,男,5岁。8个月时左侧鼻部出现米粒大褐色丘疹,逐渐增大成为红褐色结节,类似皮疹于左侧面部不断发生,病理检查示：真表皮交界处及真皮内弥散性梭形痣细胞浸润,呈对称分布,痣细胞巢垂直于表皮。免疫组化示：Ki-67（〈2%-3%＋）,HMB45（＋）,S-100（＋）。     

Agminated Spitz nevi on a hyperpigmented macule

We present the case of a 2-year-old boy with multiple Spitz nevi clustered on a hyperpigmented macule that obeyed a quadrant distribution. Multiple Spitz nevi are rare and can be disseminated or clustered. A third of the cases of agminated lesions appear on hyperpigmented macules.     

Cyclin D1 overexpression in Spitz nevi: an immunohistochemical study

The morphologic distinction between Spitz nevus and malignant melanoma can be difficult. Because cyclin D1 has been reported to be overexpressed in malignant melanomas, but not in common acquired nevi, we hypothesized that cyclin D1 might be a useful marker to distinguish Spitz nevi from malignant melanoma. Thus, we assessed for cyclin D1 expression in 11 Spitz nevi (10 compound and 1 intradermal) and 9 malignant melanomas (4 Clark stages I-III and 5 Clark stages IV-V) using an immunohistochemical method and routinely fixed and processed tissues. The cyclin D1 results were arbitrarily divided into three groups: 0% to 10%, >10% to 25%, and >25%. We confirmed the observations reported previously by others that cyclin D1 is expressed in malignant melanomas but not in common acquired nevi. Unexpectedly, a relatively high number of cyclin D1-positive cells (i.e., >10%) was also found in all cases of Spitz nevus. However, unlike malignant melanoma, the cyclin D1 positivity in Spitz nevi was present in a zonal pattern. In other words, the number of cyclin D1-positive cells decreased as the lesion extended more deeply, with the number of positive cells in the reticular dermis being less than that in the papillary dermis. Fluorescence in situ hybridization methods were used to assess amplification of 11q13, the locus harboring the cyclin D1 gene, in four cases of Spitz nevus; all were disomic. Using the antibody MIB-1, we compared cyclin D1 expression to the proliferation rate in Spitz nevi. Despite the high cyclin D1 positivity, all Spitz nevi had a relatively low number of MIB-1-positive cells (mean=3.2%), which was significantly lower than that of malignant melanomas (mean=15.3%) (p < 0.001). Thus, unlike malignant melanoma, there appears to be a dissociation between cyclin D1 overexpression and cell proliferation in Spitz nevi.     

Congenital agminated Spitz nevi: immunoreactivity with a melanoma-associated monoclonal antibody

Agminated, or grouped Spitz nevi are a curious expression of nevomelanocytic growth; and represent an uncommon manifestation of these nevi. We encountered an example of agminated Spitz nevi present at birth, which showed progression and rapid growth over months. All showed histologic Spitz nevus features. Avidin-biotin immunohistochemical techniques using anti S-100 protein, neuron-specific enolase (NSE), and melanoma-specific monoclonal antibody, HMB-45 labelled the nevi as follows: diffuse S-100 and NSE staining in most and HMB-45 positivity in sporadic cells deep in the dermis. HMB-45 reactivity occurred in both spindle cells and epithelioid forms.     

Agminated Spitz nevi: report of a child with a unique dermatomal distribution

Spitz nevi most commonly present as solitary lesions. Multiple agminated Spitz nevi are a rare presentation, with 38 reported cases in the English language literature. We report a 2-year-old girl who presented with multiple Spitz nevi in a unique, dermatome-like distribution and review the English-language literature on agminated Spitz nevi.     

Multiple agminated Spitz nevi of the penis

A case of a 7–year-old boy with multiple agminated Spitz nevi of the outer part of the prepuce is described. The normal and electron microscopic pictures are presented.     

Melanocytic nevi with features of Spitz nevi and Clark's/dysplastic nevi ("Spark's" nevi)

Background: Nevi with cytologic characteristics of Spitz nevus and architectural features of Clark's/dysplastic nevus are not well recognized in the literature.
Methods: Twenty-seven nevi with characteristics of Spitz nevus and Clark's/dysplastic nevus are reviewed.
Results: The patients' mean age was 33 years, and 17/27(63%) patients were female. Lesions were most frequent on the trunk and lower extremities. Histopathologically, these nevi were composed of large, monomorphous spindled and/or epithelioid melanocytes. Spindle cells were often oriented parallel to the epidermis, with fused rete and lamellar fibroplasias. Lateral extension of the junctional component was a feature of compound lesions. An average of 10 years of clinical follow up in 12 patients revealed no recurrence or metastasis.
Conclusions: Recognition of this type of nevus is important to avoid confusion with malignant melanoma.     

The spectrum of organoid nevi

Two patients in whom tumors developed in organoid nevi are reported. The first patient, a 50-year-old man, had a trichilemmoma arising from an organoid nevus on the scalp. The second patient, a 68-year-old woman, had a basal cell epithelioma, sebaceous epithelioma, syringocystadenoma papilliferum, and a trichilemmoma arising from an organoid nevus on the face.     

Management of Spitz nevi: a survey of dermatologists in the United States

BACKGROUND: There is no consensus concerning management of Spitz nevi. OBJECTIVE: This study was carried out to ascertain how dermatologists manage Spitz nevi. METHODS: A questionnaire was sent to 997 fellows of the American Academy of Dermatology, 284 pediatric dermatologists, and 27 directors of pigmented-lesion clinics. The results are based on the 381 questionnaires returned. RESULTS: The vast majority of responding dermatologists (93%) recommend biopsies of suspected Spitz nevi. Of this group, 43% recommend total biopsies and 55% recommend partial biopsies; 2% would recommend either total or partial biopsies, depending on the clinical situation. Sixty-nine percent of physicians would completely excise a lesion that was histologically diagnosed as an incompletely removed Spitz nevus. Seventy percent of general dermatologists and 80% of pediatric dermatologists would recommend excision with a 1- to 2-mm margin of normal-appearing skin around a Spitz nevus. Nine percent of general dermatologists would recommend margins of 4 mm or more; however, all pediatric dermatologists surveyed would recommend margins less than 4 mm. Physicians were less likely to monitor patients whose Spitz nevi were completely removed. Three fourths (74%) of respondents believe Spitz nevi are entirely benign, 4% believe they are precursors to melanoma, and 22% are not sure. Seven percent of general dermatologists and 4% of pediatric dermatologists have seen metastatic melanomas arise at sites of lesions initially diagnosed histologically as Spitz nevi; 40% of pigmented-lesion clinic directors have seen such lesions. CONCLUSIONS: We believe that the lack of consensus, both in our survey and in the medical literature, reflects to some extent the lack of certainty in the histologic differentiation of Spitz nevi from melanomas and that concern about melanoma influences management. At the pigmented-lesion clinic of the New York University Skin and Cancer Unit, because of this concern about melanoma, it is usually recommended that Spitz nevi be completely excised.     

Classic and atypical Spitz nevi: review of the literature

Both classic and atypical Spitz nevi are uncommon melanocytic lesions usually presenting in children and adolescents. The classic Spitz nevus typically is benign and has characteristic clinical and histologic features. In contrast, the atypical Spitz nevus has an unknown clinical prognosis, and its clinical and histologic traits are loosely defined. Melanoma can have similar features to both classic and atypical Spitz nevi and must be ruled out in all cases. We review the literature on classic and atypical Spitz nevi, advances in differentiating both types of nevi from melanoma, and treatment options.