1/15. Primary invasive signet-ring cell melanoma.The histopathological variants of malignant melanoma include the common type (lentigo maligna, superficial spreading melanoma, nodular melanoma, acrolentiginous melanoma), spindle cell, desmoplastic, balloon cell, pleomorphic (fibrohistiocytic), myxoid, small cell melanoma and malignant blue nevus. Recently, signet-ring cell melanoma was introduced as an additional cytologic variant. We describe a 72-year-old patient with a primary signet-ring cell melanoma of the skin located on the upper arm. Histopathologic examination disclosed a melanocytic tumor extending from the epidermis to the deep reticular dermis. Numerous pleomorphic tumor cells showed large, intracellular vacuoles and oval to spindle-shaped nuclei at their periphery. Mitotic figures and multinucleated melanocytes were also observed. Some of the signet-ring cells exhibited cytoplasmatic periodic acid-Schiff (PAS)-positivity. immunohistochemistry showed positive reaction of the tumor cells for S-100, HMB-45 protein and vimentin, confirming their melanocytic differentiation. Tumor cells were negative for cytokeratins, epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA). The signet-ring cell melanoma disclosed an invasion to Clark Level IV and tumor thickness of 2.2 mm. Signet-ring cell melanoma is a rare morphologic variant of melanoma. Its recognition is important for differentiation from other tumors featuring signet ring cells.- - - - - - - - - - ranking = 1keywords = spindle (Clic here for more details about this article) |
2/15. iris mammillations as the only sign of ocular melanocytosis in a child with choroidal melanoma.An 8-year-old girl had visual loss in her left eye over 2 months. Ocular examination showed that visual acuity was counting fingers in the left eye. The left iris was moderately pigmented and thickened with numerous confluent, dome-shaped elevations on its surface, consistent with iris mammillations arising from ocular melanocytosis. There was total retinal detachment and an inferiorly located large amelanotic choroidal mass compressing the optic nerve. A specimen from a fine-needle aspiration biopsy showed spindle and epithelioid melanoma cells. The eye was enucleated. Pathologic examination showed that the bland melanocytes comprising the anterior border layer of iris formed focal aggregates, corresponding to the iris mammillations observed clinically. The uvea was diffusely thickened. Arising from the posterior choroid and obscuring the optic nerve head was a moderately pigmented spindle and epithelioid cell choroidal melanoma with diffuse lymphocytic infiltration and high mitotic activity. This case demonstrates that iris mammillations can be the initial manifestation of ocular melanocytosis in the absence of scleral pigmentation.- - - - - - - - - - ranking = 1keywords = spindle (Clic here for more details about this article) |
3/15. Neurocutaneous melanosis: a case of primary intracranial melanoma with metastasis.Neurocutaneous melanosis is a rare disorder characterized by the presence of large or multiple congenital melanocytic naevi and benign or malignant pigment cell tumours of the leptomeninges. Distant metastasis is unusual in primary leptomeningeal/intracranial melanomas. We present the case history of an adult male who had multiple primary intracranial melanomas associated with neurocutaneous melanosis (naevus of Ota) in the ophthalmic division of the left trigeminal nerve. Excision of the intracranial tumours was carried out in two stages, but the patient died 2 days after the second operation. autopsy showed multiple metastatic deposits in the liver. Symptoms and signs of raised intracranial pressure, the presence of Ota's naevus, and a dural-based mass or masses should alert the treating physician to suspect a primary leptomeningeal/intracranial melanoma.- - - - - - - - - - ranking = 507.12234214831keywords = naevus (Clic here for more details about this article) |
4/15. Becker's naevus of the thigh with lipoatrophy: report of two cases.Although Becker's naevus is most common in males, cases with associated lipoatrophy are more frequently reported in women. Two women are described in whom Becker's naevus of the thigh was associated with localized lipoatrophy. Neither had any bony abnormality or functional deficit.- - - - - - - - - - ranking = 1521.3670264449keywords = naevus (Clic here for more details about this article) |
5/15. A variant of junctional naevus of epithelioid and spindle cell type rich in melanophages.We describe a form of junctional melanocytic neoplasm with a massive production of melanin accumulated in the dermis. The pigment is stored in macrophages, which are by far the most numerous cellular component of the lesion. Another peculiar aspect is the occasional presence of a few melanocytes scattered in a pagetoid pattern above the dermo-epidermal junction in the spinous layer. The histological picture of this lesion is similar to a form of "tumoral melanosis" induced by a regressed malignant melanoma. The lesion had a worrisome clinical picture, its dark colour constituting a clinico-pathological diagnostic problem. The main clinical clues to the benign nature of this entity are the small lateral diameter, the uniform distribution of the pigment and the stability of the lesion over time; moreover, the patients are alive and well after a considerable length of time. Although a regressed dysplastic or malignant lesion cannot be totally excluded from a scientific point of view, we conclude that there is no sound morphological or clinical evidence that the lesion is other than biologically benign. The lesion is most likely another peculiar variant of epithelioid and spindle cell naevus.- - - - - - - - - - ranking = 1270.3058553708keywords = naevus, spindle (Clic here for more details about this article) |
6/15. Atypical mole syndrome and congenital giant naevus in a patient with celiac disease.We describe a case of a 28-year-old woman affected by celiac disease (CD) associated with rare multiple disorders of the cutaneous pigmentary system: atypical mole syndrome and congenital giant naevus. Some other rare skin lesions have been reported in association with celiac disease such as cutaneous sarcoidosic granuloma, bullous pemphigoid, ichthyosis, alopecia areata, erythema elevatum diutinum, sclero-atrophic lichen and primary cutaneous amyloidosis. This is the 1(st) report concerning celiac disease and congenital disorders of the pigmentary system.- - - - - - - - - - ranking = 1267.8058553708keywords = naevus (Clic here for more details about this article) |
7/15. Hemi-naevus of Ota: perturbation of neural crest differentiation as a likely mechanism.We present a case of oculodermal melanosis that involves the lower eyelid and lower half of the globe in a very clearly defined fashion. We suggest that such a lesion is the result of a local change in embryonic environment occurring during a well-defined stage of ocular development, such that differentiation of neural crest cells into a melanocytic phenotype is favoured.- - - - - - - - - - ranking = 1014.2446842966keywords = naevus (Clic here for more details about this article) |
8/15. Two cases of atypical membranous aplasia cutis with hair collar sign: one with dermal melanocytosis, and the other with naevus flammeus.We report two atypical cases of membranous aplasia cutis surrounded by a rim of hairs, one case associated with dense dermal melanocytosis and the other with naevus flammeus, with characteristic clinical features. A rim of hypertrichosis, 'hair collar' sign, is proposed to have a close association with neuroectodermal defects. A failure of the normal closure of the cranial neural tube might have affected foetal skin development, including melanoblast migration and capillary network formation. The changes in the present cases, as well as the hair collar sign may suggest a complex hamartomatous nature of membranous aplasia cutis.- - - - - - - - - - ranking = 1267.8058553708keywords = naevus (Clic here for more details about this article) |
9/15. Two discrete uveal melanomas in a child with ocular melanocytosis.OBJECTIVE: To describe a case of two uveal melanomas in a child with mild ocular melanocytosis. methods: A 6-year-old girl was followed for 5 years with an ill-defined, slowly enlarging presumed choroidal nevus in the postequatorial fundus. Ocular oncology evaluation revealed mild sectorial scleral and uveal melanocytosis and an episcleral sentinel vessel superotemporally. Two discrete uveal melanomas were present. In the circumpapillary and macular region, tumor 1 was diffuse at 9.0 mm in base and 4.1 mm in thickness and with overlying subretinal fluid. In the ciliary body, tumor 2 was discovered by transillumination and was 6.0 mm in base and 2.2 mm in thickness. Enucleation was performed. RESULTS: Histopathologic analysis disclosed two discrete uveal melanomas in a bed of diffuse mild uveal melanocytosis. Tumor 1 was a mixed, predominantly epithelioid cell melanoma with active mitotic figures, and tumor 2 was a mixed, predominantly spindle cell melanoma. The choroid between the melanomas showed only benign, dendritic melanocytes consistent with melanocytosis. There was no extrascleral extension. CONCLUSIONS: Ocular melanocytosis can predispose to one or multiple uveal melanomas. Lifetime ophthalmic monitoring of affected patients is warranted.- - - - - - - - - - ranking = 0.5keywords = spindle (Clic here for more details about this article) |
10/15. Late onset dermal melanocytosis: an upper back variant.Seven elderly Japanese men with blue macules on their upper backs are reported. Histological examination showed this pigmentation to be melanosis due to the presence of spindle-shaped or oval pigment-laden cells in the dermis. Electron microscopy revealed the cells to be compatible with dermal melanocytes. We assume that this condition belongs to the category of late onset dermal melanocytosis and is an upper back variant. This concept has not been proposed before.- - - - - - - - - - ranking = 0.5keywords = spindle (Clic here for more details about this article) |
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