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.     

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.     

Pseudogranulomatous Spitz nevus: a variant of Spitz nevus with heavy inflammatory infiltrate mimicking a granulomatous dermatitis

Spitz nevus is a benign melanocytic proliferation that shows relatively characteristic clinicopathologic features. Despite this, Spitz nevus is clinically confused with many other lesions, and histopathologically it is sometimes difficult to distinguish it from melanoma. However, Spitz nevus rarely causes differential diagnostic problems with granulomatous dermatitis. This article describes an 8‐year‐old girl who presented with a nodule on her right arm, a clinical appearance of a pyogenic granuloma. Histopathologically, there was a dermal lesion composed of aggregates of large epithelioid cells surrounded by a heavy inflammatory infiltrate, mimicking a sarcoid‐like granulomatous dermatitis. Immunohistochemistry showed epithelioid cells with strong nuclear and cytoplasmic staining with S‐100 protein, thus establishing the diagnosis of a melanocytic tumor. The heavy T‐cell lymphocytic infiltrate that accompanies the large epithelioid cells caused its granulomatous appearance. Molecular assessment showed H27H mutation in the HRAS gene. We suggest the term ‘pseudogranulomatous’ for this variant of Spitz nevus because it indicates that the lesion is not authentically granulomatous and simply mimics a granulomatous dermatitis.     

Spitz nevus: follow-up study of 8 cases of childhood starburst type and proposal for management

Spitz nevus is an uncommon, benign melanocytic neoplasm that shares many clinical and histological features with melanoma. It presents clinical ambiguity that makes the diagnosis and management of the patient difficult. We present our experience in the management of Spitz nevus by rigorous dermoscopic long-term follow-up of 8 Spitz nevi in patients younger than 12 years. Dermoscopic images, acquired every 6 months, show evolution and modifications of these lesions. The aim of this paper is to better understand the long-term modifications of nevi with starburst pattern to avoid surgical excision of these lesions in the pediatric age group.     

Spitz nevus: a case report and the use of dermoscopy

The Spitz nevus is a benign melanocytic lesion with clinical and histopathological features similar to those of melanoma. It was first described in 1948 but great controversy still remains today with respect to its diagnosis and management. The use of dermoscopy may increase diagnostic accuracy. In Spitz nevus, the most common dermoscopic finding is a starburst-like pattern, followed by globular and atypical patterns. Diagnosis must be confirmed by histopathology, particularly in atypical cases.     

发育不良性痣11例临床病理学分析

目的 探讨发育不良性痣的临床病理学特点。方法 对11例临床表现为色素性损害的手术标本行H-E染色，结合临床指标及评分进行研究和分析。结果 临床表现：皮损直径≥5mm者8例，多发性损害者7例，边界模糊者4例，外形不规则者6例，痣表面色素不匀者4例，基底色红者6例。光镜下：交界痣3例，复合痣8例。发育不良性痣较为特异的组织学表现为真表皮交界处雀斑样增生，痣细胞巢增生紊乱倾向于形成“桥型”融合。表皮下方的非典型黑素细胞在基底层呈“Paget”样蔓延，真表皮交界处的黑素细胞向周围延伸，并超过真皮内的痣细胞成分。非典型黑素细胞：细胞核较角质形成细胞核大，多形性，出现核仁，深染。结论 临床和组织病理相结合是诊断发育不良性痣的可行性标准，仅根据组织学的非典型性不能诊断发育不良性痣。     

The spectrum of Spitz nevi: a clinicopathologic study of 83 cases

OBJECTIVE: To achieve a clinicopathologic classification of Spitz nevi by comparing their clinical, dermoscopic, and histopathologic features. DESIGN: Eighty-three cases were independently reviewed by 3 histopathologists and preliminarily classified into classic or desmoplastic Spitz nevus (CDSN, n = 11), pigmented Spitz nevus (PSN, n = 14), Reed nevus (RN, n = 16), or atypical Spitz nevus (ASN, n = 14); the remaining 28 cases were then placed into an intermediate category (pigmented Spitz-Reed nevus, PSRN) because a unanimous diagnosis of either PSN or RN was not reached. SETTING: University dermatology and pathology departments and general hospital pathology departments. PATIENTS: A sample of subjects with excised melanocytic lesions. MAIN OUTCOME MEASURE: Frequency of dermoscopic patterns within the different histopathologic subtypes of Spitz nevi. RESULTS: Overlapping clinical, dermoscopic, and histopathologic findings were observed among PSN, RN, and PSRN, thereby justifying their inclusion into the single PSRN diagnostic category. Asymmetry was the most frequent indicator of histopathologic ASN (79%; n = 11); in only 4 cases did dermoscopic asymmetry show no histopathologic counterpart, and in those cases the discrepancy was probably the result of an artifact of the gross sampling technique carried out with no attention to the dermoscopic features. CONCLUSIONS: Among Spitz nevi, histopathologic distinction between PSN and RN is difficult, not reproducible, and may be clinically useless. A simple clinicopathologic classification of these neoplasms might therefore be structured as CDSN, PSRN, and ASN. Asymmetry should be assessed using both dermoscopic and histopathologic analysis, and reliability in histopathologic diagnosis may be enhanced by the simultaneous evaluation of the corresponding dermoscopic images.     

Spitz nevi arising in speckled lentiginous nevus: clinical, histologic, and molecular evaluation of two cases

Spitz nevi are small dome-shaped nodules that sometimes arise in areas of preexisting hyperpigmentation, such as a speckled lentiginous nevus (nevus spilus), where they present a diagnostic dilemma. We report clinical, histopathological, and molecular findings of two cases of multiple Spitz nevi arising in a speckled lentiginous nevus. We used immunohistochemistry to assess expression of Ki-67, epidermal growth factor receptor, vascular endothelial growth factor, and RelA in two cases of Spitz nevi arising in a speckled lentiginous nevus. We observed rare staining for the proliferative marker Ki-67, but positive staining for the growth and antiapoptotic factors epidermal growth factor receptor, vascular endothelial growth factor, and RelA. Characterization of the molecular phenotype of Spitz nevi arising in speckled lentiginous nevi may provide a useful adjunct to long-term monitoring in this rare but difficult clinical presentation.     

Primary cutaneous signet-ring cell melanoma: a clinico-pathologic and immunohistochemical study of two cases

Signet-ring cell malignant melanoma is a rare histopathologic variant of malignant melanoma with only a few described cases. We report the clinical, histopathological, and immunohistochemical features of two cases of primary cutaneous signet-ring cell malignant melanoma. Neoplastic melanocytes showed abundant clear cytoplasm compressing the nuclei to the periphery, sometimes resulting in a signet-ring appearance. Immunohistochemically, neoplastic melanocytes in both cases expressed immunoreactivity for the usual melanocytic markers S-100 protein and Melan-A, although only the second case resulted HMB-45 positive. We review the literature about this rare cytologic variant of malignant melanoma and discuss the differential diagnosis with other cutaneous neoplasms that may show a signet-ring cell appearance of their neoplastic cells.     

Trichoblastoma is the most common neoplasm developed in nevus sebaceus of Jadassohn: a clinicopathologic study of a series of 155 cases

Nevus sebaceus of Jadassohn is a hamartoma that combines epidermal, follicular, sebaceous, and apocrine gland abnormalities. Classically, several types of cutaneous neoplasms have been associated with this hamartoma, with basal cell carcinoma being the most frequently described malignancy. We studied a series of 155 examples of nevus sebaceus of Jadassohn with clinicopathologic correlation. Several histopathologic changes related to the age of the patients were found. In our series, we could not identify any cases of authentic basal cell carcinoma. In contrast, several examples of primitive follicular induction and of trichoblastomas were seen. Other cutaneous hamartomas, hyperplasias, and neoplasms found in our series of nevus sebaceus of Jadassohn included syringocystadenoma papilliferum, sebomatricoma, apocrine gland cyst, poroma, different histopathologic variants of warts (classic warts, tricholemmoma, and desmoplastic tricholemmoma), primitive follicular induction, and ductal induction. In our series, no examples of malignant neoplasms were identified. On the basis of these findings, the classically recommended treatment for this hamartoma, which consists of early excision to prevent the development of malignancy, seems to be inappropriate.     

Cellular blue nevus with atypia (atypical cellular blue nevus): a clinicopathologic study of nine cases

Atypical cellular blue nevus (ACBN) has clinicopathologic features intermediate between typical cellular blue nevus (CBN) and the rare malignant blue nevus (MBN)/malignant melanoma (MM) arising in a CBN. Herein we report 9 cases of ACBN. The patients were caucasian (6 females and 3 males) with a mean and median age of 47/51 years. Two patients complained of recent changes and about half of these tumors were located on the buttocks or scalp, averaging 1.5 cm in diameter. Histologically, they were characterized by architectural atypia (infiltrative margin and/or asymmetry) and/or cytologic atypia (hypercellularity, nuclear pleomorphism, hyperchromasia, mitotic figures, and/or necrosis). Assessment of the expression of 3 tissue markers demonstrated rare solitary cell staining with oncogene product bcl-2, and a proliferative index of 23±19 and 39±30 cells/10 high power field with antibodies to PCNA and Mib-1, respectively. No significant differences were detected comparing the above levels of expression to a control group of 15 CBN; however, ACBNs tended to show a higher proliferative index by PCNA and Mib-1 as well as a significantly higher mitotic rate (1/10 HPF vs. 0; p=0.001). Analysis of DNA content showed DNA anetiploidy in both groups. Follow-up data on 9 of 9 patients showed 1 patient dead without disease and 8 alive without disease (mean/median follow-up 42/32 months, range 15-96 months). No patient during this follow-up time has experienced either a local recurrence or lymph node or visceral metastasis. These findings highlight the close resemblance of ACBN to the natural history of CBN. Nevertheless, many of the distinguishing histologic features of ACBN are also those of MBN. Because of these intermediate clinicopathologic features, ACBN warrant close scrutiny and long-term follow-up.     

Recurrence of melanoma in the scar after excised Spitz nevus in a 17-year-old child

Melanoma in childhood is rare and its diagnosis is more difficult than in adults, as it often presents histologic features overlapping with the Spitz nevus. The authors report the case of a 17-year old boy who was first diagnosed with Spitz nevus, however, the final diagnosis made after the excision of the tumor arising in the scar was changed to melanoma. The case in this present study emphasizes the importance of the differential diagnosis of skin tumors in young patients.