Spitz nevus

A case of Spitz nevus is presented in view of the difficulties of differentiating it from malignant melanoma. Spitz nevus with predominantly epithelioid cell is uncommon.     

Myxoid Spitz nevus

BACKGROUND: The deposition of extracellular mucin has not been described in Spitz nevus and herein such a case is reported. METHODS: A 6-year-old male presented with a growing 1.0-cm pigmented lesion on his left anterior knee. The lesion was excised. RESULTS: The histologic sections demonstrated a symmetrical and dome-shaped proliferation of spindle and epithelioid melanocytes with sharp lateral demarcation at the dermal-epidermal junction and within the superficial dermis. Features of Spitz nevus such as retraction from the epidermis, eosinophilic bodies, and uniform cytologic atypia were seen. Of interest, there was marked mucin deposition within the epidermal clefts and between the neoplastic cells. The mucin was highlighted by alcian blue and colloidal iron stains, and it was negative with mucicarmine and periodic acid-Schiff stains. CONCLUSION: Awareness that soitz nevi can rarely have extracellular mucin helps in avoiding diagnostic pitfalls.     

Hyalinizing Spitz nevus

A seventeen-year-old Korean girl had a reddish-brown papular lesion on the nose. Histopathologically, it proved to be a "hyalinizing Spitz nevus" with the characteristic features of a discohesive growth pattern of nevus cells and hyalinized stroma. Immunohistochemical stains showed positive reactivity of nevus cells with S-100 protein and Vimentin and negative stainings with HMB45, CD68, CEA and low molecular weight cytokeratin. Hyalinizing Spitz nevus may represent a variant in the spectrum of Spitz nevus.     

簇发性斯皮茨痣

报告1例簇发性斯皮茨(Spitz)痣(良性幼年黑素瘤)。患儿男,10岁。1年前左耳郭出现1枚小丘疹,曾在当地医院行手术将丘疹切除,术后2个月在手术切口周围出现数个丘疹,并逐渐增大,融合成斑片,部分皮损呈乳头瘤样。皮损组织病理学检查及免疫组化染色结果符合Spitz痣的组织病理学改变。结合临床及组织病理学改变,确诊为簇发性Spitz痣。     

Hypopigmented Reed nevus

Reed nevus, also named pigmented spindle cell nevus, is a peculiar melanocytic nevus, now regarded as a variant of Spitz nevus by the majority of authors. It is characterized by spindle-shaped melanocytes disposed in nests located in epidermis and papillary dermis. It is usually heavily pigmented, and many melanophages may also be present. Hypopigmented Reed nevus shows all the typical features of conventional pigmented spindle cell nevus, but it does not contain abundant melanin. This variant of Reed nevus is poorly described in literature, so we report five cases of hypopigmented Reed nevus and discuss its clinical and histopathological features.     

发生在斑痣上的Spitz痣5例

报告5例发生在斑痣上的Spitz痣,其中1例位于下肢,4例位于面部.5例患者临床均表现为在斑痣上出现的红色或褐色丘疹,组织病理检查均为Spitz痣.     

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.     

足跖和阴茎Spitz痣

报告2例发生在跖部和阴茎的Spitz痣。1例患者皮损位于阴茎,另1例位于跖部,其中位于跖部的Spitz痣需要和黑素瘤相鉴别。     

Spitz nevus and atypical spitzoid neoplasm

Spitz nevus (SN) and Spitzoid malignant melanoma (SMM) represent benign and malignant counterparts at both ends of the spectrum of Spitzoid lesions. Atypical Spitzoid neoplasm (ASN) is a poorly defined and characterized category of melanocytic tumors with histologic features of both benign Spitz nevi and malignant melanomas. The group of ASN represents a mixture of Spitz nevi with atypical features and Spitzoid melanomas. However, at the current moment in time, histopathologists are not capable of differentiating between the 2 in some cases and are forced to place them in this ambiguous category, where the behavior of these lesions cannot be predicted with certainty. Because this group encompasses both benign and malignant lesions, and perhaps also a separate category of melanocytic tumors that behave better than conventional melanomas, some of these neoplasms can metastasize and kill patients, whereas others have no metastatic potential, and yet others might only metastasize to regional lymph nodes. Although diagnostic accuracy has improved over the years, many of these lesions remain controversial, and there is still poor interobserver agreement in classifying problematic Spitzoid lesions among experienced dermatopathologists. The objective of this review article is to summarize the most relevant information about SN and ASNs. At this time histologic examination remains the golden standard for diagnosing these melanocytic neoplasms. We therefore concentrate on the histopathologic, clinical, and dermoscopic aspects of these lesions. We also review the most recent advances in immunohistochemical and molecular diagnostics as well as discuss the controversies and dilemma regarding whether to consider sentinel lymph node biopsy for diagnostically ambiguous melanocytic neoplasms.     

A case of combined nevus: compound nevus and spindle cell Spitz nevus

Combined nevi consisting of a Spitz nevus and an acquired nevus are unusual, and, to our knowledge, the combination of a spindle cell Spitz nevus and an overlying compound nevus has not been previously reported. We report a 17-year-old girl with a nodule on the left anterior lower extremity. The nodule was asymptomatic, firm, brown, symmetrical, dome-shaped, 8 mm in diameter, and not found with ulceration. Histological findings showed proliferation of spindle-shaped cells with an overlying compound nevus. The spindle-shaped cells were large, non-pigmented, uniform in size and shape, with rare mitoses and without nuclear atypia, and arranged in a storiform pattern in thick collagen bundles. They stained positively for S-100 and negatively for HMB-45. The lesion was considered to be a new type of combined nevus consisting of a spindle cell Spitz nevus and an overlying compound nevus.     

皮肤镜表现为落日征的Spitz痣1例

 患儿,女,1 岁。左眉弓上方内侧结节半个月。皮肤科查体：左眉弓上方内侧有一个半球形的红色结节,大小约 0.8 cm×0.6 cm,表面破溃、浆液性渗出,边界清楚。皮肤镜检查示红色均质背景,周边有黄白色鳞屑,呈现“落日征”。组织病理表现为表皮角化过度并角化不全,表皮假上皮瘤样增生,局部表皮高度水肿,水疱形成,表面可见浆痂。局部表皮内及真皮全层大量上皮样细胞增生,局部围绕附属器排列,细胞形态尚温和,偶见核裂。免疫组化：HMB-45(部分弱+),Melan-A(-),S-100 （+）,Ki-67 （3%+）,CD163(-),CD68(-)。诊断：Spitz 痣。完整切除皮损,术后6个月随访,未见复发及转移。     

Spitz nevus on the palmar surface

Relatively little is known about the incidence of Spitz nevus on palmar surfaces. This report places a case study in the context of the Japanese literature regarding the occurrence of Spitz nevus on palmar surfaces. Although the proportion of palms and soles in relation to the body surface is about 5%, the incidence of the Spitz nevus was 2%. The mean age at onset was 17.8 years, and all 4 cases were women. The clinical features were a black macule or flatly elevated small modules. The size of the lesions was relatively small, extending from 3.5 mm to 8.0 mm. Although the backs of the hands and insteps have almost the same area as the palms and soles, the incidence of onset in these regions was 6.3% (13 cases). We thus concluded that Spitz nevus tends to be rare on palms and soles.