1/51. Desmoplastic spindle-cell melanoma of the eyelid with orbital invasion. PURPOSE: To describe the clinicopathologic features of a patient with a spindle-cell melanoma of the eyelid that exhibited orbital invasion. methods: Case report. RESULTS: A slowly enlarging mass developed in the eyelid of a 50-year-old woman. Excision of the mass showed desmoplastic spindle-cell melanoma. The tumor recurred in the orbit, and an exenteration was performed. A second recurrence 7 months later was treated with radiation therapy. CONCLUSIONS: There is a continuum of spindle-cell to desmoplastic melanoma. The prognosis of patients with orbital invasion of melanoma is poor, and adjuvant treatment including radiation and chemotherapy has little benefit. ( info) |
2/51. Desmoplastic malignant melanoma on the buttock of an 18-year-old girl: differentiation from desmoplastic nevus. Melanocytic proliferation in young people may sometimes pose a diagnostic dilemma. This is particularly so when a desmoplastic component is present. Because the two main differential diagnoses, desmoplastic malignant melanoma and desmoplastic Spitz nevus, share some morphologic features, the diagnosis of desmoplastic malignant melanoma may be overlooked. Distinction between the two is important because they show completely different biological behavior. The age of patient, site of lesion, histologic findings of melanocytic atypia, neurotropism, mitosis, and maturation help to distinguish the two entities. We report a case of desmoplastic malignant melanoma occurring in the buttock of an 18-year-old Chinese girl. Histologically, it had typical features of desmoplastic malignant melanoma with junctional melanocytic atypia and prominent neurotropism. Clinical and histologic differences between desmoplastic malignant melanoma and desmoplastic Spitz nevus are reviewed. We conclude that although desmoplastic Spitz nevus occurs much more commonly in adolescents, desmoplastic malignant melanoma can occur in this age group and even in non-sunexposed skin. Microscopic findings remain the mainstay that guides the final diagnosis. ( info) |
3/51. Eruptive widespread Spitz nevi: can pregnancy be a stimulating factor? Spitz nevus is most commonly a benign solitary lesion. Agminated or disseminated Spitz nevi represent an uncommon manifestation of this nevus. We report an unusual case of Spitz nevi arising and disseminating during pregnancy. ( info) |
4/51. Plexiform spitz nevus: an intradermal spitz nevus with plexiform growth pattern. Two cases of a distinctive variant of Spitz (spindle and epithelioid cell) nevus are described. One lesion developed on the lower leg of a 17-year-old boy and the other lesion on the back of a 52-year-old man. The microscopic appearance was characterized by a plexiform arrangement of bundles and lobules of enlarged spindle to epithelioid melanocytes throughout the superficial and deep dermis. Intraepidermal melanocytic proliferation was unappreciated. Some lobules were circumscribed by a thin rim of compressed fibrous tissue. In both cases a myxoid stroma was present. The cells had abundant eosinophilic cytoplasm with well-defined borders. The nuclei were enlarged, consistently ovoid and vesicular, with small nucleoli. Both cases contained scattered multinucleate giant cells similar to those observed in classical form of Spitz nevi. No melanin pigment was detectable by light microscopy. No mitoses were observed in one case and a rare mitosis was present in the other. Tumor cells were strongly immunoreactive for S-100, but not for HMB-45, desmin, and actin. The differential diagnosis of this distinctive tumor includes desmoplastic/neurotropic melanoma, plexiform spindle cell nevus, cellular blue nevus, plexiform neurofibroma, and cellular neurothekeoma. The designation of "plexiform Spitz nevus" is chosen to emphasize its distinctive plexiform growth pattern. ( info) |
5/51. Polypoid Spitz naevus: the benign counterpart of polypoid malignant melanoma. Polypoid malignant melanoma is a peculiar morphological variant of melanoma with a distinct exophytic pattern of growth. This form of melanoma is usually very thick and the prognosis is accordingly poor. We present here a previously undescribed form of Spitz naevus which had a similar polypoid exophytic silhouette and marked cytological atypia. Despite these close morphological similarities, polypoid Spitz naevus evolves in a completely benign manner. Morphologically, polypoid Spitz naevus can be distinguished from polypoid melanoma by the absence of mitoses and by the prominent stromal reaction throughout the lesion. ( info) |
6/51. Juvenile xanthogranuloma variant: a clinicopathological case report and review of the literature. Juvenile xanthogranuloma is a relatively rare cutaneous lesion. In order to make an early diagnosis and be alert to the possibility of visceral complications and associated medical conditions, plastic surgeons should be aware of the entity. The classic presentation is that of successive eruptions in the head, neck and upper trunk of initially red papules or nodules which later become yellow and finally brown flattened plaques or macules. This report is of an unusual variant with atypical histology including frequent mitoses and a lack of Touton giant cells. ( info) |
7/51. Prepubertal malignant melanoma: report of three cases. Prepubertal malignant melanoma (MM) is an extremely rare tumor. In slovenia, 13 MM cases were registered between 1968 and 1996 by the Cancer Registry of slovenia. The diagnosis of MM was confirmed by histology in 3 children. In 3 other children the lesions initially diagnosed as MM were reclassified as Spitz nevus. In the remaining cases, the slides were not accessible for histological review, and the clinical course of disease corroborated the diagnosis of a benign nevus. In the present report, 3 of 13 cases with histologically confirmed prepubertal MM are described. The difficulties encountered in the diagnosis and management of this rare condition are discussed. ( info) |
8/51. 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. ( info) |
9/51. 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. ( info) |
10/51. Epithelioid blue nevus: a rare variant of blue nevus not always associated with the carney complex. Epithelioid blue nevus is a rare variant of blue nevus that has been recently described in patients with carney complex. Some of the patients with carney complex have multiple epithelioid blue nevi and a familial history of similar lesions is often recorded. Epithelioid blue nevus consists of an intradermal melanocytic nevus composed of polygonal epithelioid cells laden with melanin. Neoplastic cells show no maturation at the base of the lesion and, in contrast with the usual stromal changes in blue nevi, epithelioid blue nevus exhibits no fibrosis of the dermis. We have studied three cases of epithelioid blue nevus in three patients with no evidence of carney complex. The lesions were solitary and there was no family history of similar lesions. Therefore, epithelioid blue nevus is a distinctive variant of blue nevus that may also appear as a sporadic lesion and is not always associated with carney complex. ( info) |