1/25. indocyanine green angiography of optic nerve head melanocytoma.PURPOSE: To determine the features of fluorescein and indocyanine green angiography of melanocytoma. methods: Fluorescein and indocyanine green angiography is used to assess an optic nerve head melanocytoma in a 45-year-old female. RESULTS: fluorescein angiography revealed increased vascularity on the surface, with staining around the lesion in the late stages. The lesion was hypofluorescent in all stages of indocyanine green angiography. CONCLUSIONS: indocyanine green angiography is helpful in identifying the benign nature of the lesion by showing hypofluorescence, indicating lack of vascularity in the tumor.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/25. Leptomeningeal melanoma in childhood.BACKGROUND: Malignant melanoma (MM) is one of the least common types of childhood cancer, accounting for less than 1% of all pediatric malignancies. Neurocutaneous melanosis (NCM) is a rare phakomatosis consisting of congenital abnormal pigmentation of the skin and meninges. The meningeal lesions are particularly prone to malignant change. methods: The authors describe 5 patients with NCM and 1 with primary leptomeningeal melanoma (LMM) seen at 2 treatment centers in the north of england over a 13-year period (1984-1997). RESULTS: The clinical features, progress, radiological findings, and treatment of these patients are discussed. All six died within eight months of their diagnosis, illustrating the difficulties faced in treating patients with these conditions. The authors reviewed the published literature on NCM, concentrating on the various therapeutic strategies that have been tried. Very little consistency in approach was found. Malignant skin lesions in NCM may be less responsive than primary malignant melanoma, but the small number of patients with primary LMM or brain metastases of MM make comparisons with NCM difficult. The authors' own series illustrates well the piecemeal nature of therapy for patients with these rare conditions. CONCLUSIONS: The rate of incidence of MM melanoma in the U.K. is increasing, and it will represent an increasing proportion of the pediatric oncologist's workload. A consistent approach to the therapy of patients with metastatic MM and NCM is needed if we are to have any hope of offering more than palliative therapy to these children in the future.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/25. Speckled lentiginous nevus: within the spectrum of congenital melanocytic nevi.BACKGROUND: Currently, there is disagreement as to whether speckled lentiginous nevi (nevi spili) are congenital or acquired pigmented lesions. Part of this controversy is related to the natural history of these lesions that often present at birth as hyperpigmented patches and then take several years to reach their more readily recognized spotted form. Arguments in favor of speckled lentiginous nevi as a subtype of congenital nevi include the following observations: multiple reports of lesions present at birth or noted soon thereafter; patterns of distribution reflecting embryonic development; hamartomatous behavior with various types of nevi (eg, junctional nevi, blue nevi, and Spitz nevi) presenting in the same lesion over time; and histologic features of congenital melanocytic nevi within the spots. Herein we present additional evidence for the congenital nature of speckled lentiginous nevi. OBSERVATIONS: Ten patients are described with congenital pigmented lesions that had the clinical appearance of speckled lentiginous nevi in whole or in part. These lesions either evolved and acquired an appearance more suggestive of "classic" congenital nevi, or they existed as "hybrid" lesions with portions appearing as classic congenital nevi adjacent to or admixed with portions appearing as speckled lentiginous nevi. On histologic examination, biopsy specimens from the spots within these lesions showed features of congenital melanocytic nevi. CONCLUSIONS: These 10 cases, along with the arguments outlined above, provide strong support for the hypothesis that speckled lentiginous nevi are a subtype of congenital melanocytic nevi.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/25. Broad spectrum of leukoderma acquisitum centrifugum.A series of diverse neuroectodermally derived tumors associated with halos of leukoderma is presented. Clinically these lesions have in common a centrally placed, usually pigmented tumor encircled by a zone of hypopigmentation. The histological findings include (1) reduction or absence of epidermal melanin, but persistence of amelanotic melanocytes in the leukodermic halo; (2) a variety of tumors including nevus-cell nevus, neuroid nevus, blue nevus, neurofibroma, and malignant melanoma; (3) variable numbers of "small dark cells" whose nature is unclear, and which probably represent in part small nevus cells and in part lymphoid cells; and (4) damage to some tumor cells which presumably could be the cause of their destruction. Also presented are histochemical demonstrations of tyrosinase activity and immunohistochemical studies for presence of gamma-globulin in the tumors. Using the fluorescent antibody technique it was not possible to show gamma-globulins in patients' sera directed against their tumors. The relationship of developing hypopigmentation to the spontaneous regression of cutaneous neuroectodermally derived tumors is discussed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/25. Eosinophilic intranuclear inclusion bodies in a melanocytic nevus.We report a case of eosinophilic or hyaline true intranuclear inclusion bodies in a melanocytic nevus. Although intranuclear pseudoinclusions are frequently found in melanocytic nevi, true intranuclear inclusions are rare. The true intranuclear nature of the inclusions in our case was confirmed with ultrastructural examination. With reverse transcriptase in situ polymerase chain reaction (RT in situ PCR) analysis, eosinophilic bodies stained positive for molluscum-specific primers. This result suggests that such inclusions may be related to molluscum viral infection of melanocytes.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/25. Organized vitreous hemorrhage masquerading as an optic disc melanocytoma.PURPOSE: To present a case of organized vitreous hemorrhage masquerading an optic disc melanocytoma. DISCUSSION: optic nerve head melanocytoma is a benign slightly pigmented lesion arising from the edge of the disc presenting with a filed defect. Pigmented nature of the lesion in question due to presence of haemosidrin laden macrophages led a diagnostic dilemma. Trans vitreal biopsy confirmed the diagnosis. CONCLUSIONS: Althought classical in presentation organized blood clots can masquerade a number of lesions including a melanocytoma as in the present scenario.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/25. Desmoplastic hairless hypopigmented naevus: a variant of giant congenital melanocytic naevus.Desmoplasia has been described in melanoma and Spitz naevus but not in giant congenital melanocytic naevus (GCMN). In melanoma desmoplasia is associated with a better survival. Four paediatric patients with hard, ligneous, progressively hypopigmented and alopecic GCMN were seen among 143 cases of GCMN at the Department of dermatology of the National Institute of Paediatrics, mexico City. Clinically, induration was progressive in three patients and regressive in one. Pigmentation was regressive in all. Histopathologically, all four patients showed intense dermal fibrosis, scarce naevus cells, and hypotrophic or absent hair follicles. Follow-up and serial biopsies in three patients documented the progressive nature of fibrosis and naevus cell depletion. No evidence of malignant transformation was found. Naevus cell depletion resulted in pigment loss and may have reduced the risk of malignant transformation. Although the cause of fibrosis is unknown, the possibility of an immune reaction to naevus cells is postulated.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/25. Spontaneous regression of subcutaneous metastasis of cutaneous melanoma.A case is presented of a 44-year-old Caucasian man who was operated on in October of 1988 for a cutaneous melanoma in his trunk and who in the space of 1 year manifested a single subcutaneous nodule compatible with a metastasis of melanoma by fine-needle aspiration biopsy. No other abnormal findings were revealed by physical and instrumental examinations. During the subsequent hospitalization, we witnessed (in conjunction with the occurrence of painful symptoms in the hands of an inflammatory nature) the total, progressive, spontaneous regression of the metastasis, which was confirmed by the clinic and the tests. After 15 months of follow-up, the patient has not shown any further signs of illness.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/25. Blue nevus of the prostate: report of two new cases with immunohistochemical and electron-microscopic studies.Two new cases of prostatic blue nevus are studied with routine histological, immunohistochemical and ultrastructural methods. Both cases showed a chronic lower urinary tract obstruction due to a benign prostatic hyperplasia with spindle-shaped stromal cells loaded with melanin pigment. These cells were positive for S-100 and negative for HMB-45 antibodies, being, to the best of our knowledge, the first time that this antibody has been tested in prostatic pigmented lesions. The electron-microscopy study was performed in the first case, confirming the nature of these pigmented cells as melanocytes derived from the neural crest showing melanosomes in all the stages of differentiation and without complete basal cell membrane. The histogenesis of pigmented lesions of the prostate and the differences between blue nevus and melanosis are discussed, and the literature is reviewed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
10/25. Multiple focal pigmented lesions in the maxillary tuberosity and hard palate: a unique display of intraoral junctional nevi.The pigmented conditions located in the oral cavity have a diverse genesis ranging from vascular lesions to exogenous and endogenous pigmentations. In this report we have documented the unusual occurrence of multiple intraoral junctional nevi in a patient. A review of the patient's past dental records revealed that 2 of these lesions were first noticed 8 years earlier; however, no efforts were made to identify the nature of the pigmentations. Removal of 4 lesions and subsequent histopathological analysis revealed the presence of junctional nevi. This case illustrates the importance of a thorough clinical and histological work-up when dealing with pigmented lesions in the oral cavity. The excision of all suspected oral nevi is warranted because they cannot be clinically differentiated from other pigmented lesions, including oral melanoma. In addition, the potential of junctional nevi to undergo malignant transformation in the oral cavity is undetermined.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
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