1/121. melanosis in association with metastatic malignant melanoma: report of a case and a unifying concept of pathogenesis.An unusual case of melanosis associated with metastatic malignant melanoma is reported. This was characterized by progressive blue/gray discoloration of the skin of the chest and abdomen in an elderly patient, 1 year after removal of a polypoid malignant melanoma from the right arm. A biopsy of involved skin revealed perivascular aggregates of melanin-laden histiocytes throughout the dermis, the histopathologic hallmark of melanosis. An unusual aspect of the case was the coincidental finding of a tumor embolus within a small dermal vessel, probably a lymphatic. To date, neoplastic melanocytes have been detected in only a small minority of skin biopsies with features of melanosis. This case and a distillation of related information in the literature lead to the conclusion that the essence of melanosis, and the feature that distinguishes this from conventional metastatic melanoma, is the persistent and cumulative dissemination of melanin, via the bloodstream, throughout the body. This in turn leads to progressive pigmentation of all internal organs and the skin. Only continuous access to the circulation by neoplastic melanocytes could explain such a phenomenon. Potential mechanisms by which this could arise are discussed in the context of existing knowledge.- - - - - - - - - - ranking = 1keywords = melanoma, malignant melanoma (Clic here for more details about this article) |
2/121. Neurocutaneous melanosis presenting with intracranial amelanotic melanoma.We describe imaging findings in a 2-year-old girl with neurocutaneous melanosis and malignant cerebral melanoma. Because the cerebral melanoma in this child was of the amelanotic type, high-signal intensity on unenhanced T1-weighted images was not present. The cutaneous lesions played a crucial role in establishing a correct (presumed) histopathologic diagnosis on the basis of the imaging findings. To our knowledge this is the first report describing an intracranial amelanotic malignant melanoma in association with neurocutaneous melanosis.- - - - - - - - - - ranking = 0.65718847571895keywords = melanoma, malignant melanoma (Clic here for more details about this article) |
3/121. 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 = 1.2458146465817keywords = melanoma, malignant melanoma (Clic here for more details about this article) |
4/121. Simultaneous occurrence of multiple melanoma in situ on sun-damaged skin (lentigo maligna), solar lentigo and labial melanosis: the value of dermoscopy in diagnosis.We report on a patient developing simultaneous occurrence of lentigo maligna lesions, solar lentigines and an extensive melanosis of the oral mucosa. Diagnostically, epiluminescence microscopy had a relevant role in the preoperative assessment and selection of suspicious pigmented lesions, as the lesions histologically labelled as lentigo maligna and solar lentigo were clinically indistinguishable. We review the clinical, dermoscopic and histopathologic differential diagnosis of solar lentigo, malignant lentigo and mucosal melanosis with other melanocytic and keratinocytic lesions and discuss the possible relationship between these entities.- - - - - - - - - - ranking = 0.33635781192156keywords = melanoma (Clic here for more details about this article) |
5/121. Pigmented squamous cell carcinoma.Pigmented squamous cell carcinomas have been reported in the oral and ocular mucosae, but rarely in the skin. We present a case of pigmented squamous cell carcinoma of the forehead and review the current English literature. Pigmented squamous cell carcinoma can be confused with pigmented basal cell carcinomas and melanoma, especially those melanomas associated with pseudoepitheliomatous hyperplasia and should be included in the differential diagnosis of atypical pigmented lesions.- - - - - - - - - - ranking = 0.16817890596078keywords = melanoma (Clic here for more details about this article) |
6/121. Laparoscopic postmortem examination: a minimally invasive approach to the autopsy.Laparoscopic and thoracoscopic autopsies have previously only been performed on an experimental basis to determine their potential usefulness as a substitute for a conventional postmortem examination. We present the case of a patient with an unusual variant of malignant melanoma (diffuse melanosis) in whom the immediate cause of death clinically was thought to be fulminant hepatic failure, the etiology of which was unknown. The family was unwilling to consent to a conventional autopsy, but would permit a postmortem examination limited to a 2-cm abdominal incision and removal of a sample of liver. In view of the unanswered clinical questions regarding the cause of the acute hepatic failure and its possible relationship to the diagnosis of diffuse melanosis, we decided that more extensive examination of the abdominal cavity, specifically the liver, was required and that the only way that this could be accomplished was by laparoscopic techniques. Laparoscopic examination of the abdominal cavity revealed multiple melanotic nodules on the surface of the liver and studding the omentum. Multiple liver samples were easily obtained; these revealed massive diffuse necrosis of the liver parenchyma with scattered nodular deposits of dark pigment consistent with melanin. We report the first known case in which a laparoscopic autopsy was used to obtain valuable information that answered clinically relevant questions. Laparoscopic autopsy can offer the a family that is unwilling to consent to a conventional postmortem examination an alternative that can potentially provide answers to clinical questions that otherwise would have been unresolved.- - - - - - - - - - ranking = 0.1526517578366keywords = melanoma, malignant melanoma (Clic here for more details about this article) |
7/121. 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 = 0.50453671788234keywords = melanoma (Clic here for more details about this article) |
8/121. Malignant melanoma arising from unusual conjunctival blue nevus.Cellular blue nevus is an uncommon pigmented tumor in the conjunctiva, where it generally appears as a deep, circumscribed, pigmented conjunctival mass. We report a case of conjunctival blue nevus that clinically resembled primary acquired melanosis and gave rise to conjunctival melanoma. A 41-year-old man developed a diffuse pigmented mass in the inferior fornix of his left eye. Over a 20-year period, he noted slight progression of the pigment. Foci of epibulbar pigmentation were also present. The lesion resembled primary acquired melanosis. Excisional biopsy and adjuvant cryotherapy were performed. Histopathologic examination disclosed an intense infiltrate of heavily pigmented dendritic melanocytes with aggregates of less pigmented plump cells in the substantia propria. The conjunctival epithelium was normal. Malignant cellular features consistent with melanoma were observed in some foci. Cellular blue nevus of the conjunctiva can simulate primary acquired melanosis and can give rise to malignant melanoma. Arch Ophthalmol. 2000;118:1581-1584- - - - - - - - - - ranking = 0.65718847571895keywords = melanoma, malignant melanoma (Clic here for more details about this article) |
9/121. 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 = 0.58862617086273keywords = melanoma (Clic here for more details about this article) |
10/121. Diffuse melanosis arising from metastatic melanoma: pathogenetic function of elevated melanocyte peptide growth factors.The origin of diffuse melanosis resulting from metastatic melanoma is unknown. We examined the light microscopic and ultrastructural changes in the skin of an affected 35-year-old woman and determined the peripheral blood levels of melanocyte growth factors. A total of 7 biopsy specimens were examined by light and electron microscopy and immunohistology (S-100, HMB45, MART1, CD68, MAC387). serum/plasma levels of melanocyte growth factors of the patient were determined by enzyme-linked immunosorbent assays and compared with those of normal volunteers (n = 10) and amelanotic patients with metastatic melanoma (n = 10), matched to the UICC stage of the affected patient. Hyperpigmented but otherwise apparently normal skin of the patient displayed epidermal melanocyte hyperplasia, increased melanogenesis, and dermal pigment stored in histiocytes and other cells along with extracellular deposits. blood levels of alpha-melanocyte stimulating hormone, hepatocyte growth factor, and endothelin-1 were significantly elevated in the affected patient. Aberrant production of these factors may not only be responsible for activation of the pigment system in diffuse melanosis of metastatic melanoma, but also for increased proliferation, motility, and pigment incontinence of normal and malignant melanocytes.- - - - - - - - - - ranking = 0.58862617086273keywords = melanoma (Clic here for more details about this article) |
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