1/158. Giant and "granular melanosomes" in leopard syndrome: an ultrastructural study. Electron microscopy of lentigines was performed to study the pigmentation abnormality in two children with leopard syndrome. Giant melanosomes similar to those seen in cafe-au-lait spots of neurofibromatosis and nevus spilus were found in a lentigine from one of our cases. Our results show that "spherical granular melanosomes" described in neurofibromatosis, are lysosomal-like structures associated with the development of complex melanin granules. Our study also demonstrates that immature melanosomes are present in some keratinocytes of leopard syndrome. This finding is in contrast to the prevailing concept that only mature melanosomes are transferred to keratinocytes. The occurrence of individual melanosomes of normal size and shape in keratinocytes of skin in whites with leopard syndrome, suggests that neither the size of melanosomes, nor the racial differences are the factors determining the distribution of melanosomes in keratinocytes. ( info) |
2/158. Pigmented squamous cell carcinoma of the scrotum associated with a lentigo. Only 13 cases of pigmented squamous cell carcinoma (SCC) have been reported in the English language literature, with most frequent development in the oral cavity and conjunctiva. However, no case of pigmented SCC of the scrotum has been reported. We report here a case of pigmented SCC that arose primarily in the scrotum of a 70-year-old man. light microscopically, this tumour exhibited the typical features of a pigmented SCC, including not only keratinization and intercellular bridges but also colonization by plump dendritic melanocytes with marked pigmentation. These features were clearly confirmed by immunohistochemistry, including strong positivity of tumour cells for high-molecular-weight cytokeratin and of colonizing melanocytes for HMB-45. The tumour was associated with a lentiginous lesion and partly involved it. melanocytes entrapped from the lentigo might therefore have been activated during enlargement of this tumour, resulting in melanocyte colonization. Fourteen cases of pigmented SCC, including ours, are clinicopathologically reviewed. ( info) |
3/158. carney complex: in a patient with multiple blue naevi and lentigines, suspect cardiac myxoma. carney complex is characterized by spotty pigmentation (blue naevi and lentigines), myxomas (cardiac, cutaneous, mammary), endocrine over-activity (Cushing's syndrome, acromegaly), testicular tumours, and schwannomas. We report a male with multiple blue naevi, lentigines, testicular large cell calcifying Sertoli-cell tumour and four cardiac myxomas. The myxomas caused two cerebrovascular accidents and a myocardial infarction. All patients with multiple blue naevi or lentigines should be investigated for the life-threatening association of cardiac myxomas. ( info) |
| We present a patient with leopard syndrome and hyperelastic skin. Biochemical analysis using cultured skin fibroblasts showed normal type III and V collagen synthesis, lysyl hydroxylation level of type I procollagen and processing of pro-alpha(1) and alpha(2)(I). Our results suggest that molecular defects of hyperelasticity in leopard syndrome are not related to abnormal collagen metabolism, although not all steps of collagen synthesis have been investigated. ( info) |
| An 18-year-old girl with leopard syndrome is described. Clinical manifestations include lentigines, ocular hypertelorism, mental and growth retardation, deafmuteness, and several patches of hair loss on her scalp. No family history of skin lentiginosis or any other inherited condition was found. ( info) |
6/158. Blue nevi and basal cell carcinoma within a speckled lentiginous nevus. We describe an unusual case of blue nevi and basal cell carcinoma arising within a speckled lentiginous nevus and discuss the relationship between epithelial tumors and nevoid growth of melanocytes. ( info) |
7/158. Familial hypertrophic cariomyopathy and lentiginosis. Members of three generations of a family studied, manifest profuse lentiginosis and hypertrophic cardiomyopathy. The autosomal dominant inheritance of this syndrome is established. Lentiginosis should alert the physician to possible underlying heart disease. ( info) |
8/158. Simultaneous occurrence of multiple melanoma in situ on sun-damaged skin (lentigo maligna), solar lentigo and labial melanosis: the value of dermoscopy in diagnosis. We report on a patient developing simultaneous occurrence of lentigo maligna lesions, solar lentigines and an extensive melanosis of the oral mucosa. Diagnostically, epiluminescence microscopy had a relevant role in the preoperative assessment and selection of suspicious pigmented lesions, as the lesions histologically labelled as lentigo maligna and solar lentigo were clinically indistinguishable. We review the clinical, dermoscopic and histopathologic differential diagnosis of solar lentigo, malignant lentigo and mucosal melanosis with other melanocytic and keratinocytic lesions and discuss the possible relationship between these entities. ( info) |
9/158. Port-wine-stain (nevus flammeus), congenital Becker's nevus, cafe-au-lait-macule and lentigines: phakomatosis pigmentovascularis type Ia--a new combination. A 16-year-old male had brown macules in a geographic pattern with increased terminal hair on the back and dusky red partially blanchable non progressing macules on his left thigh since birth. Clinical diagnoses of Becker's nevus and port-wine-stain were made and confirmed histopathologically. In addition, he had multiple lentigines on the face and trunk and a single cafe-au-lait-macule on his chest. ( info) |
10/158. Atypical pigmented lesions following extensive puva therapy. We report a 38-year-old woman with psoriasis who developed multiple atypical lentigines following psoralen photochemotherapy (PUVA). The lentigines first appeared 12 years ago, 3 years after she commenced intermittent PUVA treatment. New lesions continued to develop over the subsequent years with further photochemotherapy. Clinically, the lentigines were strikingly atypical, deeply pigmented, dark brown or black, large stellate macules. histology of a representative lesion was consistent with a PUVA lentigo and no atypical melanocytes were seen. At present, a link between malignant melanoma and PUVA lentigines has not been established. Instead, limited evidence suggests that PUVA lentigines may be more closely linked with the risk of nonmelanoma skin cancer. ( info) |