Pagetoid spitz nevus

BACKGROUND: Melanocytic tumors driven by MAP2K1 in-frame deletions are among the most recently described class of melanocytic neoplasms. The reported range of diagnoses and associated genomic aberrations in these neoplasms is wide and includes melanomas, deep penetrating melanocytomas, and pigmented epithelioid melanocytoma. However, little is known about the characteristics of these tumors, especially in the absence of well-known second molecular "hits." Moreover, despite their frequent spitzoid cytomorphology, their potential categorization among the Spitz tumors is debatable...

BACKGROUND: Pagetoid Spitz nevus is a rare subtype of Spitz nevus usually found on the lower extremities, particularly on the thigh of women. As a rare and under-recognized entity that can be misdiagnosed as melanoma, further characterization of clinical and histopathological features is needed to improve its recognition. METHODS: A retrospective analysis of all melanocytic neoplasms from the thigh diagnosed over a 3-year period. RESULTS: Fifty-five (15...

Angiomatoid Spitz nevus (ASN) is a rare histological variant of Spitz nevus (SN) that is characterized by prominent blood vessel proliferation around the intradermal melanocytes of SN. In contrast, SN may have pagetoid components, which are characterized by epidermal proliferation of single melanocytes. However, cases of ASN with predominant pagetoid melanocytic proliferation in the epidermis have not been reported. Here, we report a case of ASN with surrounding pagetoid melanocytic proliferation without formation of tumor nests in the epidermis in the plantar region...

The histopathologic differentiation between Spitz nevus and melanoma is of particular interest in routine diagnostic procedures of melanocytic tumors. Atypical Spitz nevi are sometimes difficult to distinguish from melanoma. There is still no single criterion that ensures a distinction of melanoma and atypical Spitz nevus. The aim of this study was to reevaluate established and new criteria to differentiate Spitz nevus from melanoma more reliably. We analyzed 25 melanomas with a Breslow index ≥ 1 mm and 18 classical compound Spitz nevi concerning their histopathologic, immunohistochemical and molecular genetic characteristics...

BACKGROUND: Pagetoid Spitz nevus is an uncommon Spitz nevus variant characterized by a predominantly intraepidermal proliferation of single epithelioid melanocytes. Recognition of this variant is important to avoid misdiagnosis as melanoma. METHODS: We reviewed and characterized 12 pagetoid Spitz nevi diagnosed at a tertiary care institution over the past 25 years. RESULTS: All patients were female and average age at biopsy was 34 years. Clinically, 83% (10 out of 12) were located on an extremity and all were ≤ 6 mm in diameter...

A case of atypical ("pagetoid") compound Spitz nevus on the face of a 2-year-old girl is reported with a review of the literature. The nevus was composed of broad but laterally demarcated compound proliferation of enlarged fusiform and epithelioid melanocytes, with florid pagetoid scatter above the junction. Immunohistochemical analyses revealed the Ki-67 proliferation index to be relatively low. Given the histomorphological overlap with melanoma, an array-based comparative genomic hybridization approach revealed a subthreshold gain in chromosome 1q and gain in distal chromosome 17q, with no other associated chromosomal gains or losses...

Spitz nevus is a benign melanocytic lesion and also one of the main differential diagnosis of melanoma. A descriptive and retrospective study of surgical specimens from patients with a diagnosis of Spitz nevus was conducted at two institutions in Niterói - RJ. 32 cases were analyzed. The most frequent histological subtype was compound (60 %), with a predominance of epithelioid cells (17 cases - 53%). Pagetoid spread was observed in 21 cases (68%). Maturation of melanocytes was present in 13 cases (81%). Kamino bodies were found in eight cases (25%)...

BACKGROUND: Spitz naevi may present a wide spectrum of morphologies. Histopathologically, many variants, including desmoplastic, angiomatoid, verrucous/polypoid, plexiform, pagetoid, halo, myxoid, granulomatous and tubular Spitz naevi have been described. Clinical and dermoscopic features of these unusual variants of Spitz naevi have been reported only rarely. OBJECTIVES: The aim of this study is to describe clinical, dermoscopic and histopathological features of uncommon morphological variants of Spitz naevi in order to raise awareness among clinicians about their peculiar patterns of presentation...

Predicting clinical behavior of atypical Spitz tumors remains problematic. In this study, we assessed interobserver agreement of diagnosis by 13 expert dermatopathologists for atypical Spitz tumors (n=75). We determined which histomorphologic features were most heavily weighted for their diagnostic significance by the experts and also which histomorphologic features had a statistically significant correlation with clinical outcome. There was a low interobserver agreement among the experts in categorizing lesions as malignant versus nonmalignant (κ=0...

BACKGROUND: Amelanotic melanoma represents a diagnostic challenge both clinically and dermoscopically. Few studies based on case series have explored the possibility of using reflectance confocal microscopy (RCM) to diagnose amelanotic melanoma. OBJECTIVES: To validate a new confocal feature, named hyporeflective pagetoid cells (HPCs), for the diagnosis of amelanotic melanoma. METHODS: A group of 20 amelanotic melanomas and a control population of nonpigmented melanocytic naevi (10), hypo/nonpigmented nonmelanocytic lesions (20) and pigmented melanomas (20), imaged by RCM, were retrospectively evaluated...

Spitz nevus is one of the most difficult melanocytic lesions to diagnose in regard of malignancy, even for experienced dermatopathologists. We analyzed 28 tumors with Spitzoid morphology from 15 children (three little children 2-4-year-old, 12 peripubertary children 9-17-year-old) and 13 adults; there were 21 Spitz nevi, five atypical Spitz tumors and two Spitzoid melanomas in order to establish the diagnostic value of several morphologic parameters in different age groups. No significant differences in respect of age and/or tumor type occurred for gender, location, dimension, symmetry, sharp lateral demarcation, junctional nests orientation, adipose tissue extension, side-to-side cytologic symmetry, uniform melanin deposits, nuclear pleomorphism, presence of mitoses, inflammation and epidermal alterations...

Determining risk assessment for aggressive behavior of atypical Spitz tumors (ASTs) remains a significant challenge for pathologists. Despite the presence of many concerning histological features such as tumor ulceration, expansile growth, dermal mitotic rate, and cytological atypia, the overwhelming majority of these tumors behave in an indolent fashion. Recently, we have noted that using cytogenetics, one can identify ASTs with high likelihood for aggressive behavior allowing for a clinically significant risk assessment...

BACKGROUND: Differentiating Spitz nevi from melanoma can be difficult. Pagetoid spread of melanocytes is among the features making diagnosis difficult. Rare reports of isolated pagetoid Spitz nevi exist. OBSERVATIONS: We present a unique case of multiple pagetoid Spitz nevi initially diagnosed as multiple in situ melanomas. Germline karyotyping, CDK4 and CDKN2A sequencing, and comparative genomic hybridization of HRAS, BRAF, KRAS, RAF1, CDKN2A, Rb1, MAP2K1, MAP2K2, PTEN, and PTPN11 genes did not identify mutations in this case...

Pagetoid proliferation of single melanocytic cells or small nests of melanocytes may be seen in a variety of melanocytic neoplasms including pagetoid spitz nevi, de novo epithelioid melanocytic dysplasia, and melanoma. Distinction of these entities may be difficult as there is considerable clinical and histologic overlap in these entities. Patient outcome and management may be significantly influenced by the pathologists' impression. In this study, we collected 24 cases of superficial melanocytic neoplasms with prominent pagetoid melanocytosis...

OBJECTIVE: To test the interobserver and intraobserver reproducibility of the standard terminology for description and diagnosis of melanocytic lesions in in vivo confocal microscopy. DESIGN: A dedicated Web platform was developed to train the participants and to allow independent distant evaluations of confocal images via the Internet. SETTING: Department of Dermatology, University of Modena and Reggio Emilia, Modena, Italy. PARTICIPANTS: The study population was composed of 15 melanomas, 30 nevi, and 5 Spitz/Reed nevi...

INTRODUCTION: Desmoplastic Spitz nevus is a rare variant of spitzoid tumours characterized by dermal proliferation of large epitheliod and/or fusiform melanocytes within a desmoplastic stroma, comprising thick, eosinophilic collagen bundles. It occurs most frequently in young adults and children, and exhibits a predilection for the limbs. Histologically, this entity may be mistaken for cutaneous fibrous tumours or desmoplastic melanoma. To establish useful histological criteria for differential diagnosis of desmoplastic Spitz nevus, we conducted a retrospective study comparing data concerning the clinical, demographic and histological characteristics of desmoplastic Spitz nevus and desmoplastic melanoma...

Spitz nevus is an infrequent, usually acquired melanocytic nevus composed of epithelioid and/or spindle melanocytes that can occasionally be confused with melanoma. Currently, there are no immunohistochemical markers or molecular biology techniques that can be used to make an entirely safe diagnosis of Spitz nevus or melanoma in problematic cases. A retrospective study has been carried out that included all the cases diagnosed as Spitz nevus from our files. Follow-up information of the patients was unavailable...

OBJECTIVES: To identify in vivo microscopic substrates of the dermoscopic patterns of melanocytic lesions and to correlate them with histopathologic features. DESIGN: Before excision, lesion areas that showed characteristic dermoscopic patterns were imaged by dermoscopy and confocal microscopy and directly correlated with histopathologic features. SETTING: Departments of Dermatology of the University of Modena and Reggio Emilia and Hospital Clínico of Barcelona, between July 2006 and March 2007...

BACKGROUND: Among the pigmented lesions with a central area of scar, we found a group of cases histologically characterized by striking architectural alteration of the melanocytic component, but with no cytological atypia and mitotically quiescent. The aim of the current study was to assess the biological nature of such lesions. METHODS: We selected 19 of these melanocytic neoplasms that had the following characteristics: (a) a clinically evident whitish central area suggestive of regression (with no history of a previous surgical procedure or trauma), (b) histological features of fibrous scar-like tissue at the center of the lesion, (c) the presence of large, confluent and unusually shaped melanocytic nests at the dermoepidermal junction and in the dermis, (d) a pagetoid spread of melanocytes above the epidermal basal layer and (e) remnants of nevus tissue at the border of the scar...

BACKGROUND: In dermoscopy the presence of a blue hue is a clue for malignancy, although a blue tint is sometimes observable in benign lesions. OBJECTIVE: To identify the in vivo confocal microscopy correlates of the blue hue for improving diagnostic accuracy for melanoma. METHODS: Fifty-seven melanomas, 41 junctional, 88 compound, and 27 Spitz nevi were studied by dermoscopy, confocal microscopy, and histopathology. RESULTS: Confocal microscopy enabled the distinction between blue areas and blue veil, the former characterized by plump cells corresponding to melanophages and inflammatory infiltrate at histology, the latter by the contemporary presence of epidermal and dermal features consistent with diagnosis of melanoma, such as disarranged pattern, pagetoid cells, cytologic and architectural atypias, nonhomogeneous and cerebriform clusters, and dermal nucleated cells...