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At least 19 recordsLinked to original sources

Neurocutaneous melanosis: clinical features of large congenital melanocytic nevi in patients with manifest central nervous system melanosis.

BACKGROUND: Patients with a large congenital melanocytic nevus (LCMN) may have associated leptomeningeal melanocytosis with or without central nervous system (CNS) melanomas. These patients are considered to have neurocutaneous melanosis, a disorder that, when symptomatic or otherwise manifest neurologically, carries a poor prognosis even in the absence of malignancy. OBJECTIVE: Our purpose was to identify typical clinical features in patients who have manifest CNS melanosis in association with LCMN. METHODS: The records of 117 patients with LCMN in the New York University Registry of LCMN and the reports of 172 cases of LCMN in the world literature were included for features that might signal a high risk for the development of manifest CNS involvement. RESULTS: Of the 289 patients with LCMN, 33 had manifest CNS melanosis. In all 33 in whom symptomatic neurocutaneous melanosis was diagnosed, the LCMNs were present in a posterior axial location on the head, neck, back, and/or buttocks. "Satellite" nevi were known to be present in 31 of the 33 patients. CONCLUSION: Patients with LCMN in a posterior axial location, especially when associated with "satellite" melanocytic nevi, are at greater risk for the development of manifest neurocutaneous melanosis than patients with LCMN limited to the extremities or those who are lacking satellite nevi.

Adolescent↗

Melanosis coli--histochemical and immunohistochemical comparison of the pigments of melanosis coli and Dubin-Johnson syndrome.

We compared the pigment of melanosis coli with the pigment of Dubin-Johnson syndrome, melanin, and lipofuscin. The pigment of melanosis coli appeared similar to lipofuscin in that it stained positively with periodic acid-Schiff, oil red-0 and Victoria blue stains and revealed negative reactions to the immunohistochemical stains for S-100 protein and neuron specific enolase, but had similarity to melanin as shown by the positive reaction to Fontana-Masson stain and negative autofluorescence. The pigment of Dubin-Johnson syndrome showed the same histochemical and immunohistochemical characteristics as that of melanosis coli. The results indicate that the pigments of melanosis coli and Dubin-Johnson syndrome are identical and are variants of lipofuscin.

Colonic Diseases↗

Friction melanosis, friction amyloidosis, macular amyloidosis, towel melanosis: many names for the same clinical entity.

Macular or friction amyloidosis is a cutaneous entity characterized by a brownish pigmentation distributed on the skin over bony regions of the trunk and limbs after the use, for many years, of a nylon towel or scrub brush to clean the skin. Electron microscopy is necessary for the diagnosis of this dermatosis and reveals deposits of amyloid in the papillary dermis. This condition is relatively unknown in Western countries. In this report, we describe 24 Italian patients affected by friction amyloidosis which was caused by the use of cotton towels, horse-hair gloves or artificial and rough sponges to clean their skin.

Adult↗

Melanosis coli--a harmless pigmentation or a precancerous condition?

UNLABELLED: Melanosis coli has long been considered as a harmless pigmentation of the colorectum associated with the use of laxatives containing anthraquinone. Recent experimental and clinical studies, however, have provided some evidence of a possible association between melanosis coli/laxative use and colorectal cancer. METHODS: In 2.229 consecutive patients we retrospectively analyzed the association of melanosis coli and laxative use with colorectal neoplasia. All the patients had undergone total colonoscopy, and the colorectal neoplasias had been examined histopathologically in accordance with the WHO classification. Information concerning laxative use, bowel habits and family history of colorectal cancer was obtained from the medical records. The statistical analysis was done using the Mantel-Haenszel-test for linear association. RESULTS: The presence of colorectal cancer was not associated with melanosis coli or laxative use. However, colorectal adenomas were found significantly more frequently in patients with melanosis coli than in those without melanosis (p = 0.0002). But adenomas associated with melanosis coli were significantly smaller than those not associated with melanosis (p < 0.0001), and were located predominantly in the proximal colon (p = 0.0002). In the patients with melanosis coli the relative risk was significantly higher for tubular (1.80; 95% CI: 1.26-2.56) and tubulovillous adenomas (2.03; 95% CI: 1.09-3.76), but not for villous adenomas. No significant differences were found in the grade of dysplasia of adenomas in patients with, and those without, melanosis coli. CONCLUSION: There appears to be no association between colorectal cancer and melanosis coli or laxative use. Colorectal adenomas are more frequently found in patients with melanosis coli. Colorectal adenomas do not contain the melanin-like pigmentation. The association of adenomas with melanosis coli can be explained by the ease of detection of even tiny polyps as white spots within a dark-colored colonic mucosa.

Adenoma↗

Potentially life-threatening primary acquired melanosis.

Primary acquired melanosis is an acquired conjunctival pigmentation seen in Caucasians. It presents as a diffuse, patchy, unilateral area of pigmentation that can be flat or nodular. Other melanotic lesions such as ocular melanosis, argyrosis, congenital conjunctival melanosis can be confused with primary acquired melanosis. Diagnosis and management of primary acquired melanosis is critical since it is potential life-threatening. A 51-year-old while male presented with unilateral, diffuse, patchy pigmentation first noted 10 years prior. Slit lamp examination revealed a 4 mm x2 mm area of temporal bulbar conjunctival pigmentation extending to the limbus in the right eye. A biopsy was performed and pathologic examination disclosed primary acquired melanosis with atypia. Topical mitomycin-C therapy was initiated. Because of the large size and diffuse nature of the pigmentation, mitomycin-C was preferred since surgical excision would be destructive and has related risks of scarring, goblet cell loss, and associated side effects such as dry eye and ulceration. Two months, following treatment with mitomycin-C, significant clinical improvement was observed. A careful patient history is key in diagnosis primary acquired melanosis including a detailed history including onset, duration, stability, and progression of the pigmentation. All cases of primary acquired melanosis should be referred for biopsy. If atypia is found, traditional treatment includes surgical removal or cryotherapy. However, if the area is large side effects can occur. Mitomycin-C eliminates these potential side effects and can be used to successfully treat primary acquired melanosis.

Journal Article↗

Laryngeal melanosis: report of four cases and literature review.

OBJECTIVE: Laryngeal melanosis is a rare condition defined by the presence of melanocytes within the laryngeal epithelial lining. Our aims were (1) to review our cases together with those in the literature, and (2) to determine whether melanocyte incidence is increased with exposure to irritant stimuli such as tobacco. METHODS: A retrospective study of all cases diagnosed with laryngeal melanosis in our hospital from January 1, 1990, to December 31, 1996, was accomplished. To determine the melanocyte incidence in the normal larynx as well as the influence of tobacco in development of laryngeal melanosis, 16 age-matched controls, 8 of whom were smokers and 8 of whom were not, were chosen, and a histochemical and immunohistochemical study was performed. The following antibodies were used: S-100 protein, CD1a, and HMB-45. A comparative study of the melanocyte incidence between patients with laryngeal melanosis and the controls was carried out. Also, a comparative study between smoking and nonsmoking patients was performed. RESULTS: Laryngeal melanosis was diagnosed in 4 patients at our hospital during this period of time. In the comparative study, the number of melanocytes in the 4 patients with laryngeal melanosis was higher than in the 8 smoking (p < 0.01, Mann-Whitney U test) and 8 nonsmoking (p < 0.01) controls, and there was a trend toward a higher number of melanocytes in the 8 smoking patients than in the 8 nonsmoking (p = 0.064) controls. CONCLUSIONS: Laryngeal melanosis was more frequent in smoking men older than 50 years. Our observations underline the association of LM with larynx carcinoma and its relation to a stimulus such as tobacco. In fact, we have found activated melanocytes in our cases of laryngeal melanosis. They were identified by immunoreactivity for HMB-45.

Aged↗

Primary acquired melanosis of the conjunctiva is melanoma in situ.

This essay places the concept of "primary acquired melanosis" of the conjunctiva in historical perspective and shows that it and its analogs, namely, lentigo-melanosis (Hutchinson), melanotic freckle (Hutchinson), melanose circonscrite precancereuse (Dubrueilh), melanotische precancerose (Miescher), lentigo maligna (Clark), precancerous melanosis (Reese), benign, precancerous, and cancerous melanosis (Zimmerman), atypical melanocytic hyperplasia (Silver et al.), and benign acquired melanosis (Zimmerman), are synonyms for melanoma in situ. The issue is not merely semantic or philosophical; it is urgently practical. If a clinician takes literally the meaning of a lesion designated "benign melanosis" and considers it to be benign, rather than the malignant melanoma that it actually is, a patient who bears that flat pigmented lesion may one day die of metastasis from an elevated sequella of it. The same is true of "primary acquired melanosis," which is not simply a condition of blackening by melanin, but a flat melanoma that, if not removed completely, may give rise one day to metastases that cause death. To avoid such misconstructions, we advocate naming melanomas in all organs "melanoma" and those that are confined to epithelial structures "melanoma in situ." Euphemisms like lentigo maligna and primary acquired melanosis are evasions of the diagnosis of melanoma, and use of them may be harmful. For that reason, they should be eschewed.

Conjunctival Neoplasms↗

Melanosis of the rectum in patients with chronic constipation.

In patients with constipation the prevalence of melanosis in rectal biopsies was evaluated in an attempt to correlate its occurrence with laxative consumption and intestinal stasis. Melanosis was present in 58 percent of the patients and in none of a control group. Melanosis was present in 73.4 percent of patients consuming anthracene laxatives and in 26.6 percent of those not consuming anthracene laxatives (P less than 0.01). No correlation was found between the occurrence (and grading) of melanosis and pattern of transit through the large bowel, bowel movements, and duration of symptoms. Results of this study seem to indicate that intestinal stasis is not a cause of melanosis of the colon and rectum and confirm that melanosis may well be due only to the consumption of anthracene laxatives; melanosis coli does not appear to be a sensitive marker of impairment of motor function in the "cathartic colon."

Adolescent↗

Giant congenital melanocytic nevi: the significance of neurocutaneous melanosis in neurologically asymptomatic children.

Patients with a giant congenital melanocytic nevus can develop melanotic tumors characterized by central nervous system involvement, termed leptomeningeal melanocytosis or neurocutaneous melanosis. Although symptomatic neurocutaneous melanosis is rare, we previously reported distinct magnetic resonance (MR) findings of T1 shortening, strongly suggestive of neurocutaneous melanosis, in 30 percent (6 of 20) of children with giant congenital melanocytic nevi who presented initially without neurological symptoms. The purpose of this study was to determine the incidence of neurocutaneous melanosis in high-risk patients and its long-term clinical significance. Magnetic resonance imaging was recommended for all 46 patients with "at-risk" giant congenital melanocytic nevi involving the skin overlying the dorsal spine or scalp. The clinical histories and follow-up of these patients were evaluated by retrospective chart review. Forty-two underwent MR imaging of the brain and 11 underwent additional MR scanning of the spinal cord. Abnormalities were identified in 14 of 43 MR studies, and 23 percent (n = 10) had T1 shortening indicative of melanotic rests within the brain or meninges. None had associated masses or leptomeningeal thickening. The most common areas of involvement in these 10 included the amygdala (n = 8), cerebellum (n = 5), and pons (n = 3). In the group of 11 patients with spinal MR scans, a tethered spinal cord was demonstrated in one. Additional abnormalities were detected by MR scanning, including a middle cranial fossa arachnoid cyst, a Chiari type I malformation, and a crescentic enhancement that subsequently resolved. Clinical follow-up averaging 5 years (range, 2 to 8 years) revealed that only one of the 46 patients evaluated developed neurological symptoms, manifested as developmental delay, hypotonia, and questionable seizures but no other signs of neurocutaneous melanosis. No patient has developed a cutaneous or central nervous system melanoma. Magnetic resonance findings of neurocutaneous melanosis are relatively common, even in asymptomatic children with giant congenital melanocytic nevi. Although these findings suggest an increased lifetime risk of central nervous system melanoma, they do not signify the eventual development of symptomatic neurocutaneous melanosis during childhood.

Brain↗

Melanosis coli. Prevalence, distribution, and histologic features in 200 consecutive autopsies at Kuopio University Central Hospital.

The occurrence of large-bowel melanosis was evaluated by microscopy in 200 large bowels at autopsy. Melanin was seen as yellow-brown pigment in the macrophages of the lamina propria. The pigment stained with diastase-alcian blue PAS, Fontana, and iron stains. One hundred nineteen of 200 (59.5 percent) bowels showed melanosis, which was equally common in both sexes. Usually more than one segment was involved (most commonly, four segments). Melanosis was common in the proximal part of the colon, but much rarer in distal parts (sigmoid and rectum). Affected segments were successive; negative segments between positive ones were exceptional. If the rectum was affected, all five proximal segments were affected in 11 of 12 cases. The intensity of melanosis was directly related to the number of segments involved. In the oral part of the colon, affected males had a higher intensity of melanosis than affected women, but about the same intensity in the sigmoid and rectum. The fraction of patients with melanosis increased with age. Of men and women in the age group of 20 to 54 years, 32 and 44 percent were affected, and above the age of 75 years, 76 and 67 percent, respectively.

Adult↗