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PubMed1976

Melanosis of the prostate gland: report of a case with neoplastic epithelium involvement.

Prostate gland melanosis is an uncommon lesion and the precise histogenesis is unclear. Melanin may be found within melanocytes in the prostatic stroma, within prostatic epithelium and, rarely, in both locations. The stromal dendritic cell has been shown to contain premelanosomes and melanosomes suggesting primary melanin production by this cell. The melanogenic potential of prostatic epithelial cells has not yet been conclusively established. An example of prostatic melanosis is presented in which stromal and epithelial components were found. This dual distribution of melanin has been regarded as an indication that melanin in the epithelial cells results from phagocytosis of melanin from stromal melanocytes as a secondary phenomenon. Melanin pigment was identified not only within hyperplastic prostatic epithelium but also was found in the epithelial component of a well differentiated prostatic adenocarcinoma.

Adenocarcinoma↗
PubMed1995

Prevalence of primary acquired melanosis and nevi of the conjunctiva and uvea in the dysplastic nevus syndrome. A case-control study.

PURPOSE: To investigate whether conjunctival and uveal nevi and primary acquired melanosis are more common in individuals with the dysplastic nevus syndrome than in control subjects derived from the general population. METHODS: Power calculations were used to determine the sample size. After invitation, 162 individuals with the dysplastic nevus syndrome and 119 control subjects, matched for sex and age but otherwise randomized from the Stockholm county census file, were entered into the study. All individuals were examined in a masked fashion by the same ophthalmologist, and the presence of conjunctival and uveal melanocytic lesions and the iris color, skin type, and hair color of each individual were recorded. Contingency tables and odds ratios were used for statistical evaluation. RESULTS: The proportions of individuals with the dysplastic nevus syndrome featuring primary acquired melanosis of the conjunctiva, or nevi of the iris and choroid were not significantly different from those of control subjects. However, individuals with the dysplastic nevus syndrome appeared to have a more sun-sensitive skin type and a reddish or blond hair color more often than control subjects. CONCLUSION: In contrast to previous reports, this study suggests that ocular melanocytic lesions are no more common in individuals with the dysplastic nevus syndrome than in the general population. Therefore, this work does not provide support that periodic ophthalmic surveillance of individuals with the dysplastic nevus syndrome for the purpose of detecting conjunctival or uveal melanomas, or their precursors, is meaningful.

Adult↗
PubMed2005

[Nodular melanoma on primary acquired conjunctival melanosis].

A 74-year-old woman consulted for bloody tears. The etiology was a large conjunctival nodular melanoma hidden in the left superior fornix that had developed quietly on an unknown primary acquired melanosis. In this report the clinical and histological features as well as the treatment are presented. A decisional tree summarizes the treatment for conjunctival melanosis.

Age Factors↗
PubMed2004

[Melanosis of the bladder: a very uncommon entity].

Melanosis of the bladder is a rare entity characterized by anomalous deposits of melanin-containing pigment on the vesical urothelium without melanocytic atypia or associated malignant melanoma. To our knowledge and following such strict criteria, there are only five cases previously reported. The biological potential of this entity is uncertain because of the rarity of their. We report one case of simple melanosis of the bladder confirmed by histological examination and inmunohistochemistry analysis. We believe that recognition of this entity is important.

Aged↗
PubMed1993

Excimer laser ablation of conjunctival epithelial melanosis.

Two patients with conjunctival epithelial melanosis received a 193 nm argon fluoride excimer laser treatment. In both patients the melanosis was easily removed with a smoothing technique using the excimer laser. The ablated area showed normal appearing conjunctiva. The lesion did not recur during the eight-month follow-up. Therapeutically, the excimer laser can be used to treat benign conjunctival lesions as well as superficial corneal diseases.

Adult↗
PubMed1996

Granulocyte/macrophage colony-stimulating factor is an intrinsic keratinocyte-derived growth factor for human melanocytes in UVA-induced melanosis.

Recently we demonstrated that endothelins secreted from human keratinocytes act as intrinsic mitogens and melanogens for human melanocytes in UVB-induced melanosis. We show here that UVA-induced melanosis is associated with other keratinocyte-derived growth factors, secretion of which is specifically stimulated after exposure of human keratinocytes to UVA. Medium conditioned by UVA-exposed human keratinocytes elicited a significant increase in DNA synthesis by cultured human melanocytes in a UVA dose-dependent manner. Analysis of endothelin-1 and interleukin (IL)-1 alpha in the conditioned medium by ELISA, both of which are major keratinocyte-derived cytokines involved in UVB-associated melanocyte activation, revealed that UVA exposure did not cause human keratinocytes to stimulate the secretion of the two cytokines. In contrast, the levels of several other cytokines such as IL-6, IL-8 and granulocyte/macrophage colony-stimulating factor (GM-CSF) were significantly increased in the conditioned medium of human keratinocytes after exposure to UVA at a dose of 1.0 J/cm2. The gel chromatographic profile of UVA-exposed keratinocyte-conditioned medium demonstrated that there were two factors (P-1 and P-2) with molecular masses of approx. 20 and 1 kDa respectively that stimulate DNA synthesis in human melanocytes, and the larger species (P-1) also increased melanization as assessed by [14C]thiouracil incorporation. Quantitative analysis of cytokines in chromatographic fractions by ELISA revealed the P-1 fraction to be consistent with the molecular mass profile of GM-CSF. Furthermore the stimulatory effect of the P-1 fraction on DNA synthesis in human melanocytes was neutralized by antibodies to GM-CSF, but not to basic fibroblast growth factor or stem cell factor. Binding and proliferation assays with recombinant GM-CSF demonstrated that human melanocytes possess specific binding sites for GM-CSF(Kd 2.11 nM; binding sites, 2.5-3.5 x 10(4) per cell), and recombinant GM-CSF at concentrations of more than 10 nM significantly stimulated DNA synthesis and melanization. These findings suggest that GM-CSF secreted by keratinocytes plays an essential role in the maintenance of melanocyte proliferation and UVA-induced pigmentation in the epidermis.

Cells, Cultured↗
PubMedDate not supplied

Cerebral mass due to neurocutaneous melanosis: eight years later.

Neurocutaneous melanosis (NCM) is associated most commonly with giant congenital melanocytic nevi (CMN), in particular those on the scalp or in a posterior axial location that are accompanied by satellite congenital nevi. It also can occur in patients with multiple medium-sized CMN. In general, the prognosis of those with symptomatic NCM is poor, even in the absence of malignancy, while the prognosis of those with asymptomatic NCM detected via screening varies and is more difficult to predict. Herein we report an asymptomatic patient with a giant CMN and multiple satellite nevi who had a screening magnetic resonance imaging (MRI) study at age 5 months that showed a rounded area of increased signal in the right temporal lobe on T1-weighted images, suggestive of parenchymal melanosis. This melanotic mass was resected at age 10 months, and histologic examination of the surgical specimen showed prominent perivascular collections of benign, pigment-containing melanocytes within cerebral tissue. The patient remains healthy 8 years later. His excellent long-term outcome and other reports of NCM with localized central nervous system (CNS) involvement apparent on MRI may have implications for management, including early imaging of patients with high-risk CMN and potential surgical intervention for NCM.

Brain Neoplasms↗
PubMedDate not supplied

Neurocutaneous melanosis in association with the Dandy-Walker complex, complicated by melanoma: report of a case and literature review.

Neurocutaneous melanosis is a rare congenital neurocutaneous syndrome in which benign and malignant melanocytic tumors of the leptomeninges with large or numerous congenital melanocytic nevi develop. The Dandy-Walker malformation occurs as a broad posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilation of the fourth ventricle communicating with the posterior fossa. Association of these entities is very unusual and only 10 previous reports were found in the literature. Our patient had multiple, medium-size to small melanocytic nevi present since birth. At 5 years of age the patient has intracranial pressure secondary to hydrocephalus. A diagnosis of Dandy-Walker malformation and suspected neurocutaneous melanosis was established after a skull computed tomography (CT) scan. Three months later the patient developed a right frontal tumor shown on the CT scan. The histologic finding was nevomelanocytic infiltration with strong pleomorphism. The tumor grew rapidly, producing neurogenic shock and death. The postmortem report indicated malignant melanoma.

Brain Neoplasms↗
PubMed2001

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.

Adult↗
PubMed2006

[Melanosis of the urinary bladder--a case report with 10 years of follow-up and review of literature].

INTRODUCTION: Extradermal melanotic lesions are found predominantly in the oral cavity, colon or conjunctiva, and by far less frequently in other organs. We report for the first time a case of solitary melanosis of the urinary bladder with a follow-up of more than 10 years. CASE REPORT: A 48-year old man presented with symptoms of frequency, urge incontinence, obstructive voiding symptoms and nocturia. On urethrocystoscopy under general anaesthesia, melanosis of the bladder with visibly reduced bladder capacity was diagnosed and confirmed on biopsy. The patient was treated for his micturation problems with alpha-blockers, intravesical electrostimulation and GAG-substitution therapy, without success. The chronic progression of bladder symptoms and shrinkage eventually led to cystoprostatectomy and bladder replacement by an orthotopic ileal neobladder, 10 years after primary diagnosis. CONCLUSION: The very low number of reported cases accounts for the lack of management guidelines for this disease. Symptomatic treatment as well as repeated cystoscopic monitoring are logical therapeutic recommendations. Since the development of malignant disease can only be ruled out microscopically, repeated biopsies or prophylactic cystectomy need to be considered.

Biopsy↗
PubMed1998

[Mitomycin C in treatment of conjunctival melanoma and primary acquired melanosis].

BACKGROUND: Since 1995 we have used Mitomycin C additionally in the treatment of conjunctival melanoma and primary acquired melanosis. METHODS: We report on the therapy results of 14 patients suffering from pigmented conjunctival lesions (malignant melanoma 9 and primary acquired melanosis 5). After local excision, cryotherapy or irradiation all patients received one eye drop Mitomycin C (0.02%) four times daily for four to six weeks. RESULTS: We observed regression of the pigmentations in 11 cases after median follow up of 13.1 months. In one patient there was no change. Two cases showed progression with tumefaction. There were no adverse reactions except conjunctival hyperemia during therapy. CONCLUSIONS: Topical administration of Mitomycin C may be useful in the treatment of pigmented conjunctival lesions. Longer follow-up periods are necessary.

Adolescent↗
PubMed2001

Becker's melanosis in a woman.

Becker's melanosis is a relatively common, benign hamartoma, which is usually characterized by a hyperpigmented, hypertrichotic patch on the upper trunk or proximal upper extremities of males, with its onset during the peripubertal years. Commonly, there is an associated smooth muscle hamartoma on histology. We present a woman with a Becker's melanosis on the leg without hypertrichosis. We believe that the spectrum of Becker's nevus is greater than commonly thought and that cases similar to ours are not rare, but have been diagnosed as other conditions.

Adult↗
PubMed2001

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.

Adult↗
PubMed2001

Immunohistochemical detection of the c-met proto-oncogene product in the congenital melanocytic nevus of an infant with neurocutaneous melanosis.

Transgenic mice overexpressing hepatocyte growth factor/scatter factor (HGF/SF) demonstrate extensive pigmented nevi in both skin and leptomeninges of the central nervous system resembling human neurocutaneous melanosis. We immunohistochemically detected HGF/SF receptor, Met, in a congenital nevus of an infant with neurocutaneous melanosis, indicating that deregulation of HGF/SF-Met signaling in the critical period of development may lead to this fatal syndrome.

Animals↗
PubMed1991

Melanosis and associated tumors in transgenic mice.

Melanosis was found to various extents in a wide array of tissues of all 23 autopsied mice whose transgene consisted of the tyrosinase promoter fused to the simian virus 40 early-region oncogenic sequences. Pigmentation in a given animal was attributable to any or all of the following; an increase in numbers of some normally pigmented cells of neural crest origin (a result compatible with early stages of transformation); elicitation of melanin synthesis in some cells that normally have little melanin, or none at all (the latter possibly signaling metaplasia); unusual intercellular transfer of pigment granules from melanocytes into certain normally unpigmented epithelia and endothelia; and profusion of melanin-phagocytizing cells. Neoplasms, occasionally also containing melanin, arose in association with some of these melanotic tissues and included three choroid plexus tumors, three endocardial tumors, two peripheral nerve sheath tumors (schwannomas), two cochlear tumors, two pineal gland tumors, one salivary gland tumor, and one nasal mucosa tumor. These apparently originated independently of the ocular and cutaneous melanomas found in the same animals. The events involved in melanosis may thus contribute to neoplastic conversion.

Animals↗
PubMedDate not supplied

4-Hexylresorcinol as inhibitor of shrimp melanosis: efficacy and residues studies; evaluation of possible toxic effect in a human intestinal in vitro model (Caco-2); preliminary safety assessment.

Studies were performed on the efficacy, residues and in vitro enterocyte toxicity of 4-hexylresorcinol (4-HR), which could be utilized as an inhibitor of shrimp melanosis (black spot). Mediterranean sea shrimp (Parapaeneus longirostris) were treated with solutions of 4-HR in sea-water, at three different concentrations, 25, 50 or 100 mg/kg of shrimp, to test its antioxidative property. As a comparison a group of shrimp was treated with sodium metabisulphite (1 g/kg), while another group was left untreated. 4-HR showed a marked ability to inhibit or slow down melanosis (black spot) in shrimp; the most effective concentration was 100 mg/kg within an optimum period of 7 days but with effects up to the tenth day. During the first 5 days, 4-HR residues in the edible part of the shrimp showed a fast decrease in all three groups, going from initial average values of 20 mg/kg at 0 time, to 0.9 in the group treated at 25 mg/kg; from 42 to 1.8 mg/kg in the group at 50 mg/kg and from 85 to 1.9 mg/kg in the group at 100 mg/kg. In vitro studies on enterocyte-like Caco-2 cells did not indicate any cytotoxic effect up to a concentration of 50 micrograms/ml. Moreover, no inhibition of protein synthesis was observed, which lends further support to the absence of significant damage to the intestinal mucosa induced by 4-HR. The available database on 4-HR pharmacology and toxicology is inadequate to determine even a provisional ADI. There is negative evidence of carcinogenesis and no significant untoward effects were observed in humans when it was used as an anthelmintic. However, it is not possible to determine a NOEL for non-genotoxic effects. 4-HR could become an interesting alternative to the use of sulphites to prevent black spot. However, a more complete database is needed to achieve a regulatory evaluation.

Animals↗
PubMed1996

Melanosis peritonei associated with enteric duplication cyst. A case report.

Melanosis peritonei is extremely rare, and only five cases have been reported in the English literature, four in association with ovarian dermoid cysts, and one with a peritoneal cyst. We describe an additional case occurring in a girl two years of age who also had an enteric cyst. This is the first reported case of melanosis peritonei not associated with an ovarian teratoma, but with an enteric duplication cyst. Melanophages were present focally in the submucosa, superficial muscle layer, and ulcer bases of the cyst and extensively as small nodules on the peritoneal surface and in the omentum. The tendency of perivascular nodular aggregation of melanophages favors a hematogenous (or lymphatic) spread rather than implantation. Although clear evidence of melanocytic aggregation is lacking, are speculate that the melanin originated from the esophageal-like squamous mucosa of the cyst.

Child, Preschool↗
PubMed1996

Q-switched ruby laser treatment of mucocutaneous melanosis associated with Peutz-Jeghers syndrome.

Peutz-Jeghers syndrome is an eponym for circumscribed mucocutaneous melanosis in association with gastrointestinal polyposis. Irregular pigmented macules of varying size and color can be found on the perioral skin, lip vermillion border, buccal mucosa, palate, and tongue. Previous treatments, such as surgical excision, cryosurgery, electrodesiccation, dermabrasion, and carbon dioxide or argon laser ablation commonly result in incomplete removal, scarring, or changes in normal pigmentation. The Q-switched ruby laser used at 694 nm, a wavelength well absorbed by melanin relative to other optically absorbing structures in skin, causes highly selective destruction of pigment-laden cells. In addition, the 20-nanosecond pulse duration produced by this laser approximates the thermal relaxation time for melanosomes, thereby confining the energy to the target. The Q-switched ruby laser produces clinically significant fading of mucocutaneous melanosis in association with Peutz-Jeghers syndrome without complications often seen with other therapeutic modalities.

Adolescent↗