UNASSIGNED: Leptomeningeal melanocytomas are rare tumours originating from neural crest derived melanocytes. They are usually solitary and presentation with multifocal meningeal melanocytoma is very rare and indicative of potentially more aggressive behaviour. This case report and scoping review sought to evaluate the presentation, and key radiological features that can help differentiate multifocal meningeal melanocytoma from other differentials and provide a discussion of the key management and prognostic points once these tumours are diagnosed.
UNASSIGNED: A 26 year old male presented with neck pain radiating to both shoulders and subjective weakness in left shoulder movement. MRI demonstrated a large enhancing C2-C3 intradural-extramedullary lesion with further lesions at the T7/T8 level, left cerebellopontine angle and midline suprachiasmatic region. Whilst the imaging appearances were initially thought be indicative of a phacomatosis such as NF2-related schwannomatosis, surgical excision of the cervical tumour confirmed a melanocytic tumour of leptomeningeal origin, consistent with multifocal meningeal melanocytoma. Patient made a good post-operative recovery and remains under half yearly radiological surveillance, with repeat MRI 6 months after surgery demonstrating subtle growth of the untreated intracranial and spinal lesions.
UNASSIGNED: This is the first description, to our knowledge, of a multifocal meningeal melanocytoma associated with both cerebellopontine angle and suprasellar lesions. This case and included scoping review highlight the need to consider this rare diagnosis whenever multifocal craniospinal lesions are encountered, and the need to consider aggressive management through surgical resection and adjuvant craniospinal radiotherapy once these tumours are diagnosed.

Piebaldism is a rare genetic disorder caused by KIT mutations and clinically characterized by fixed depigmented patches throughout the body. Herein, a case of piebaldism in which the depigmented patches regressed as the patient grew older, along with the development of multiple café-au-lait macules, is described. The likely pathogenic, heterozygous KIT c.1991-2A>G variant was detected as the potential cause of this unusual piebaldism phenotype. This case provides new knowledge on genotype-phenotype correlation of KIT mutations for piebaldism etiology and presentation.

Melanocytes are highly specialized dendritic cells that synthesize and store melanin in subcellular organelles called melanosomes, before transfer to keratinocytes. Melanin is a complex pigment that provides colour and photoprotection to the skin, hair and eyes. The process of synthesis of melanin is called melanogenesis and is regulated by various mechanisms and factors such as genetic, environmental and endocrine factors. The knowledge of the pigmentation process is important to understand hypopigmentation disorders such as vitiligo and also to design adequate treatments. In the present work, we review the signalling pathways involved in vitiligo. Finally, current therapies and treatments including topical, oral and phototherapies are discussed and described, emphasizing future therapies based on different pigmentation mechanisms.

Dermal melanocytosis includes several benign pigmented lesions which present as blue-gray color which is a result of the color transmission of melanin pigment through the dermis. While some types are present at birth, there is an acquired variant, acquired dermal melanocytosis (ADM), which usually involves faces of middle-aged Asian women. To the best of our knowledge, there are limited reports of extra facial ADM which all are on the trunk and extremities. Herein, we report a unique case of extra facial ADM affecting the scalp of a middle-aged man and provide a review of all extra facial ADM cases that have been reported.

Intraoral melanoacanthoma is a rare, reactive pigmented lesion that is mostly seen in black individuals with a tendency to occur more frequently in younger females. The color of melanoacanthoma may vary from brown to black, and it is commonly seen as a solitary lesion in the buccal mucosa. This lesion requires no treatment, and no malignant potential has been observed to date. The clinical presentation of multifocal oral melanoacanthoma (MOMA) (the rate of growth and the recurrence) is usually diagnostic. On the other hand, solitary oral melanoacanthoma might be difficult to diagnose, and a biopsy should be performed and examined by a well-trained oral pathologist. Here, we report two cases of MOMA with an unusual location in one case.

Spotted grouped pigmented nevus is a distinct form of non-giant congenital melanocytic nevi. Histopathologically, it tends to proliferate around the skin appendages. We report a case of a 10-year-old boy with clinical and pathological findings consistent with the diagnosis of spotted grouped pigmented nevus of more than 20 cm diameter, which is considered giant.

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BACKGROUND: Primary diffuse leptomeningeal melanomatosis (PDLM) is an extremely rare pathologic condition that can mimic several other neurologic disease states.
METHODS: We report a rare case of PDLM without evidence of a primary focus. In addition, we performed a comprehensive review of the literature to describe all previously reported cases of PDLM.
RESULTS: In the reported case, making the diagnosis of PDLM was difficult. A brain and frontal dural biopsy was nondiagnostic. Computed tomography of the chest, abdomen, and pelvis did not show any distinct solitary mass. After a positron emission tomography scan was performed that showed lumbar sacral enhancement, lumbar dorsal rootlet biopsy was initiated, which was diagnostic of PDLM. Our literature review found 32 previously reported cases of PDLM. Sixteen cases (48.5%) had a distinct focus or mass discovered on imaging workup. The reported case was the seventeenth reported case of PDLM without a distinct focus or mass found on imaging workup.
CONCLUSIONS: PDLM is an extremely rare disease, and diagnosis is difficult because of nonspecific clinical, radiographic, and laboratory findings. In approximately half of cases, no distinct mass is shown on imaging workup, which may further complicate diagnosis. PDLM should be on the differential diagnosis for cases of diffuse dural enhancement. Neurosurgical intervention is often limited to ventriculoperitoneal shunting for increased intracranial pressure and dural and cranial biopsy to obtain diagnosis. If the initial biopsy is nondiagnostic, hypermetabolic activity as seen on positron emission tomography may be helpful to find an alternative biopsy site.

UNASSIGNED: Vitiligo is characterized by the idiopathic destruction of melanocytes, probably of autoimmune etiology, that results in depigmented patches of skin and mucosal surfaces. Oxidative stress may contribute to the pathogenesis of vitiligo. Zinc, a trace element with antiapoptotic properties, plays a major role in the process of melanogenesis and elimination of free radicals. The present study was conducted with the aim of comparing serum zinc levels in patients with vitiligo and in normal controls.
UNASSIGNED: In this case-control study, we studied 103 patients with vitiligo and 103 healthy sex-and age-matched controls. Serum zinc levels were measured in these two groups using atomic absorption spectrophotometry and compared with each other.
UNASSIGNED: The mean serum zinc level was 92.1 mcg/dl in the focal vitiligo, 81.3 mcg/dl in the generalized vitiligo, and 91.8 mcg/dl in the control group. A significant difference in serum zinc levels was observed between the patients with generalized vitiligo and the controls. Lower serum zinc levels were also correlated with longer duration of the disease. Furthermore, a negative relationship was found between serum zinc level and age of patients with vitiligo.
UNASSIGNED: Serum zinc level is low in patients with generalized vitiligo. In these patients, serum zinc level is in negative correlation with patient\'s age and disease duration.

Intracranial epidermoids are generally seen as hypodense nonenhancing lesions on computed tomography scans; and, as T1 hypointense and T2 hyperintense lesions on magnetic resonance imaging (MRI). Unusual radiological findings have been reported earlier. The authors present the case of a 54-year old male patient who had prior intracranial surgery. On MRI, there was a thick peripheral mantle of diffusion restriction with a central core of brilliant T1 hyperintensity and very black T2 hypointensity. The peripheral mantle showing diffusion restriction was heterogeneously T1 hypointense and T2 hyperintense. At surgery, there was a typical pearly white epidermoid peripherally with a greenish-brown centre. Pathology showed abundant extracellular melanin which was also found in the basal layer. The authors present the first case of a melanin pigmented intracranial epidermoid in literature, describing a new histological subtype.