Genomic analysis of a case of agminated Spitz nevi and congenital-pattern nevi arising in extensive nevus spilus.

Nevus spilus is a melanocytic neoplasm characterized by a tan macular background punctuated by multiple hyperpigmented macules or papules that represent various types of nevi. These include junctional and compound nevi, Spitz nevi, and rarely blue nevi. We report a unique case of widespread, multiple nevi spili giving rise to agminated Spitz nevi and congenital-pattern compound nevi. We performed genetic analysis to further characterize the mutational profile of this rare entity.

Malignant transformation of kissing nevus- a rare entity.

BACKGROUND: Kissing nevus is a congenital nevus in adjacent parts of the eyelids. Malignant transformation of kissing or divided nevi of the eyelids is rarely described. OBJECTIVE: To report a very rare case of malignant transformation of kissing nevus with ocular and extraocular spread. CASE: A 57- year- old man with 6/6 visual acuity in both eyes presented with a kissing nevus present since birth in right upper and lower eyelids which had a slow growth phase. The upper lid in the area of the nevus was thickened with a 20x12x15 mm black pigmented crusted hemorrhagic nodular lesions. The lower lid had a 6 mm black pigmented ulcerated lesion over the pre-existing nevus in the lateral third of the lid with full thickness infiltration. Another 5x4 mm pigmented lesion over the lower medial lid margin with a thickness of about 3 mm extended to the conjunctival side of the lower lid. Right sided pre-auricular and sub-maxillary nodes were palpable. A biopsy of tissue samples from the eyelid and pre-auricular nodes were consistent with malignant melanoma. CONCLUSION: Malignant transformation of kissing nevus is rare. It can spread to the conjunctiva,pre-auricular and sub-mandibular lymphnodes.

Nodular lesions arising in a large congenital melanocytic naevus in a newborn with eruptive disseminated Spitz naevi.

Congenital malignant melanoma within a pre-existing large congenital melanocytic naevus (CMN) is exceedingly rare. Its incidence is difficult to determine due to the small number of reported cases and because of problems associated with diagnosis. Some benign nodular proliferations (called proliferative nodules) arising in CMN, while rare, are significantly more common and can mimic malignant melanoma clinically or histologically. There are no reported cases of congenital melanoma or benign proliferative nodules in CMN in patients who also had eruptive disseminated Spitz naevi. We describe a girl who was noted to have a dark-brown plaque with several large erythematous nodules affecting the scalp at delivery, in addition to multiple erythematous dome-shaped papules that developed in a disseminated manner over several months, beginning at 10 days of age. It was difficult, not only clinically but also histologically, to determine the benign or malignant nature of all of these lesions. As primary cutaneous melanoma, atypical proliferative nodules in CMN, bland CMN or CMN with foci of increased cellularity and Spitz naevi show clear differences in the genetic aberration patterns, comparative genomic hybridization (CGH) could be a diagnostic help in ambiguous cases such as this. CGH performed on this patient showed multiple DNA copy number changes in the most atypical nodule, but such alterations could not be found in the remainder of the lesions. CGH showed differences between the nodular lesions that occurred in the CMN and helped us in supporting the diagnosis of this unique case of benign proliferative nodules and a possible congenital melanoma arising in a large CMN, associated with multiple widespread eruptive Spitz naevi.

State of the art, nomenclature, and points of consensus and controversy concerning benign melanocytic lesions: outcome of an international workshop.

The following communication summarizes the proceedings of a one-day International Workshop focusing on the histology of benign melanocytic nevi. Areas of controversy identified in 6 focus sessions were the nomenclature and relationships among common nevi including nevi with halo reactions, traumatized nevi, "dysplastic" nevi, and nevi from particular anatomic sites; developmental biology and frequency of malignant transformation associated with congenital nevi; the characterization and biologic nature of atypical spitzoid neoplasms; the basic definition of particular melanocytic cellular phenotypes, and the nomenclature and biologic nature of many candidate blue nevi, combined nevi, and other controversial lesions such as deep penetrating nevus and pigmented epithelioid melanocytoma. Concentrated data collection and follow-up, molecular characterization, and future consensus Workshops may facilitate the resolution of some of these problems. The Group recommended the description of ambiguous or "borderline" lesions as tumors with indeterminate or uncertain biologic/malignant potential. The participants also advised that such lesions at a minimum should be managed by complete excision with clear surgical margins.

Immunophenotype and possible origin of nevi with phenotypical heterogeneity.

Biphenotypical nevi or nevi with phenotypical heterogeneity consist of phenotypically different cell populations in a pattern other than that observed in classical combined nevi or in various maturation stages of banal nevocellular nevi. Besides several well-known entities such as deep penetrating nevi and plexiform spindle cell nevi, this category of pigment cell lesions also harbors fewer delineated lesions such as nevi with atypical dermal nodules (N-ADN) and nevi with a focal atypical epithelioid cell component (N-FAECC). Their worrisome histology may result in a wrong diagnosis of malignancy. In order to discriminate them from malignant melanoma and to shed light on their histogenesis, we analyzed the immunophenotypical profile of 33 N-FAECC, 6 N-ADN, and 10 giant congenital nevi removed shortly after birth, using antibodies directed to S100 protein, gp100, tyrosinase, NKI-C3, Melan-A and Mib-1. In N-FAECC and N-ADN, the large polygonal cells expressed gp100, S100 protein and Melan-A, and reacted with monoclonal antibody NKI-C3. In addition, there was intense tyrosinase expression but no Mib-1 immunoreactivity. Unexpectedly, we observed similar single or clustered, large epithelioid cells in three out of ten giant congenital nevi; these cells showed a similar phenotype to those observed in N-ADN and N-FAECC. Our histological and immunohistochemical data suggest that N-FAECC and N-ADN may reflect different stages of the same disorder. Moreover, their resemblance to the large polygonal cells in congenital nevi may suggest that the histogenesis of N-ADN and N-FAECC may be related to the persistence and expansion of large epithelioid cells in congenital nevi shortly after birth.

Congenital Spitz nevus clinically mimicking melanoma.

The differentiation between atypical variants of Spitz nevus and melanoma is often difficult given the many clinical and histopathologic similarities between the two. We report a case of an infant with a congenital scalp lesion exhibiting clinical features of melanoma, including variegation and regression of pigmentation and a rapidly changing appearance. Histologic examination of the excised lesion revealed a benign congenital Spitz nevus. This case emphasizes the need for clinical and histologic correlation in determining the benign or malignant nature of atypical pigmented lesions in infants.

Congenital giant melanocytic nevus with pigmented epithelioid cells: a variant of epithelioid blue nevus.

Epithelioid-cell blue nevus is an unusual cytologic variant of blue nevus that has been recently described mostly in patients with Carney complex, although the lesion may also appear in patients with no evidence of Carney complex. This variant of blue nevus is composed of melanin laden large polygonal epithelioid melanocytes situated within the dermis. The neoplastic cells show no maturation with progressive descent and, in contrast with the usual stromal changes in blue nevi, epithelioid-cell blue nevus exhibits no dermal fibrosis. This report describes a congenital giant melanocytic nevus with pigmented epithelioid cells located on the back of a 2-year-old male. The lesion was present at birth and the patient had no evidence of Carney complex. Histopathologically, the lesion consisted of a large and entirely intradermal melanocytic nevus composed of heavily pigmented epithelioid melanocytes involving the full-thickness of dermis, but extending also to the subcutaneous fat and underlying soft tissues. Immunohistochemically, epithelioid neoplastic melanocytes expressed immunoreactivity for S-100 protein, HMB-45, Melan-A, NK1C3, and microphthalmia transcription factor (MiTF) antibodies. MIB-1 cellular proliferation marker was expressed in the nuclei of only a few scattered epithelioid melanocytes. This report demonstrates that epithelioid-cell blue nevus is a distinctive histopathologic variant of blue nevus that may also appear as a giant congenital melanocytic nevus.

Congenital spitz nevus.

BACKGROUND: Congenital Spitz nevus has been reported previously in the literature, but the histopathologic features have not been examined in detail. OBJECTIVE: To histologically examine and report on congenital Spitz nevus. METHOD: We examined 10 clinically submitted congenital melanocytic nevi that were histopathologically identified as congenital Spitz nevi and compared them to the characteristics seen in acquired Spitz nevus and superficial congenital melanocytic nevus. RESULTS: Of the 10 congenital Spitz nevi, 9 were compound and 1 was dermal. Two showed features of combined Spitz nevus (Spitz and blue). Six cases showed all 16 listed characteristics of acquired Spitz nevus, with two cases having 15 and two cases having 14 characteristics. Of the superficial congenital melanocytic nevus characteristics, all except three cases had all 12 attributes. The one dermal lesion had all the characteristics of the acquired Spitz nevus and all but one of the characteristics of the superficial congenital melanocytic nevus in regards to intradermal findings. CONCLUSIONS: Congenital Spitz nevi are true congenital lesions, with histopathologic features of both acquired Spitz nevus and superficial congenital melanocytic nevus.