No abstract available.
Epidermal Cyst* ; Melanins*

The term 'primary melanocytic neoplasm' covers a wide disease spectrum, from well differentiated meningeal melanocytoma to malignant melanoma, its most aggressive malignant counterpart. Previous reports have shown that due to the paramagnetic effect of melanin, melanocytic neoplasms show high signal intensity on T1-weighted images and very low signal intensity on T2-weighted images, with relatively homogeneous contrast enhancement. The differentiation of leptomeningeal malignant melanoma from benign melanocytoma is important because of their different prognosis but on the basis of imaging findings alone is difficult. Ultrastructural immunohistochemical analysis is a possible alternative. We report the imaging findings of rare primary malignant melanoma, revealed by noncontrast-enhanced CT as a high-density mass, and demonstrating high signal intensity on T1-weighted images, and very low signal intensity on T2WI, with relatively good contrast enhancement.
Melanins ; Melanoma* ; Prognosis

No abstract available.
Hypopigmentation* ; Melanins* ; Melanocytes* ; Melanosis*

We have experienced a case of neurofibromatosis with unusual giant pigmentation, which presents itself as a 28 cm x 40 cm sized, serrated bordered light brownish patch speckled with small dark hyperpigmented macules on his back. Histopathologic examinations of light brown patch and speckles showed only an increase in basal melanin pigmentation.
Melanins ; Neurofibromatoses* ; Pigmentation*

BACKGROUND: The growth of cells is closely related to components in a culture medium. There are many reports about cellular characteristics of melanocytes grown in a PMA-contained medium. However, only a few reports have been studied by using a physiologic mitogens-contained medium. To understand melanocyte in vivo, it is necessary to know the cellular biology of melanocytes grown in a physiologic mitogens-contained medium. OBJECTIVE: To investigate any differences between melanocytes grown in phorbol 12-myristate 13-acetate(PMA)-contained medium and in physiologic mitogens-contained medium. METHOD: We examined morphology, number and melanin contents of cultured human melanocytes grown in a PMA-contained medium and physiologic mitogens-, such as bFGF, ET-1 and a a-MSH contained medium. Result : The results are summarized as follows : 1. There were no significant morphologic differences between cells in PMA-contained medium and in physiologic mitogens-contained medium. 2. The number of melanocytes were significantly more numerous in PMA-contained medium on the 2nd day (p<0.05), but significantly less numerous in the same medium on the 6th day (p<0.05). So, the proliferation rate of melanocytes in PMA-contained medium became lower than in physiologic mitogens-contained medium as time went by. 3. Melanocytes grown in PMA-contained medium had significantly increased melanin contents regardless of the time (p<0.05). Conclusion : The proliferation of melanocytes was better in physiologic mitogens-contained medium, the melanization was higher in melanocytes of PMA-contained medium.
Humans* ; Melanins ; Melanocytes*

We report two cases of dyschromatosis symmetrica hereditaria. One is a 12-year- old female and her family had five individuals with similar pigmentary disorder through three generation. The other is a 22-yesr-old female who had no family history of similar disease. Fontana-Masson stain revealed increased and decreased melanin granules in the basal cell layers in the pigmented and depigmented lesions respectively.
Female ; Humans ; Melanins

No abstract available.
Female ; Humans ; Melanins*

It has been generally assumed that eccrine poroma ariees from acroayringium, epidermal sweat duct unit. One of the characteriatics of thie structure is abaence of melanocytes and melanin granules among ite cells. Hmvever, a cornplete abeence of melanocytes and melanin granules in eccrine poroma is not invariable and a few reparts of such an occurrenee were presented, We report a case of eccrine poroma on the area below lateral malleolus af left foot. Microscpically melanin granules, confirmed by the use of Fontana Masson stain, were found in some of the tumor cells.
Foot ; Melanins* ; Melanocytes ; Poroma* ; Sweat

Atypical junctional melanocytic hyperplasia is a rare condition with unknown etiology. It is characterized by focal atypical melanocytic proliferation limited in the basal layer. Although this lesion is difficult to separate from melanoma in situ (MIS), it could be distinguished from MIS by the lack of several features, including lateral spread, upward epidermal migration, marked cytologic atypia, finely granular "smoky" melanin pigment, mitotic figures, and a subjacent host inflammatory response. In one study, atypical junctional melanocytic hyperplasia was found in 6.2% (25/400) of otherwise normal intradermal nevi. However, to our knowledge, no case of atypical junctional melanocytic hyperplasia with intradermal nevus has ever been published in Korean dermatologic literatures. Herein, we report a rare and interesting case of atypical junctional melanocytic hyperplasia with intradermal nevus.
Hyperplasia ; Melanins ; Melanoma ; Nevus, Intradermal

Omphalith generally consists of keratinous materials and sebum. It gradually forms a stone-like hard, dark brown to a black mass in elderly persons with deep umbilical depression and not clean umbilicus. A 75 years old male noticed a brownish black nodule on the umbilical depression 2 weeks ago. He did not try to remove it. This nodule gradually became to project from umbilical depression accompanied with intermittent pain. Removed specimen was brownish black stonelike on projecting polypoid lesion, but in umbilical depression, yellowish brown and not so hard. Histopathological examination showed a small quantity of melanin granules, but no nuclear components of cells.
Aged ; Depression ; Humans ; Male ; Melanins ; Sebum ; Umbilicus