A single-point mutation in exon 15 of the BRAF gene has recently been reported in a high percentage in cultured melanoma cells and in 6 of 9 primary melanomas examined. To evaluate the impact of the T1796A BRAF mutation, we screened primary melanomas, various types of nevi and lesions where a melanoma developed in an underlying nevus. We could detect the mutation in 28 of 97 (29%) melanomas and in 39 of 187 (21%) nevi, including blue nevi (0/20) and Spitz nevi (0/69), which did not carry the mutation. In melanomas with an underlying nevus, either the mutation was present in both the laser-microdissected nevus cells and the laser-microdissected melanoma cells (3/14) or both lesions were negative for the BRAF mutation except one case. In conclusion, mutations in exon 15 of the BRAF gene are nonspecific for progression of a nevus to a melanoma. Other so far unknown cofactors seem to be of importance.
Infantile myofibromatosis is a distinctive type of fibromatosis that usually develops during the immediate perinatal period. There are variants with solitary and multiple tumors. Lesions confined to the skin, soft tissue, and bone carry a good prognosis, showing spontaneous regression. The prognosis, however, is much less favorable when visceral lesions are present and the outcome may be fatal. Only recently it became obvious that there is an adult counterpart of infantile myofibromatosis, characterized by solitary lesions that have a predilection for involve the dermis and show no tendency to regression, although they have an entirely benign biological behavior. These lesions have been named cutaneous myofibroma or solitary myofibroma of adults. We have studied the clinical, histopathological and immunohistochemical characteristics of 53 examples of cutaneous adult myofibroma. In addition, 2 cases were examined ultrastructurally. The patients were mostly adults with ages ranging from 6-83 years. The lesions presented as solitary, usually painless nodules of variable duration on the skin, usually located on the extremities. Histopathologically, four patterns were identified: nodular or cellular type, multinodular or biphasic type, leiomyoma-like or fascicular type, and vascular type. A correlation between the histopathologic pattern and the lesional age was observed: vascular type of cutaneous adult myofibroma in early lesions, nodular and multinodular lesions in fully developed lesions, and leiomyoma-like or fascicular type in late lesions. Immunohistochemically, the spindle cells were desmin negative, but expressed immunoreactivity for vimentin, pan-smooth muscle actin, and alpha-smooth muscle actin. Ultrastructurally, neoplastic cells showed characteristics of undifferentiated mesenchymal cells with features of fibroblasts, myofibroblasts and pericytes. Primitive vascular formations were seen in the form of irregular clefts between adjoining cells. We conclude that cutaneous adult myofibroma is a little-known benign vascular neoplasm probably derived from myopericytes.
In a prospective audit, the prevalence, key causes and treatment of insomnia prior to admission were evaluated in a population of hospice patients using a questionnaire based on a review article of key features related to insomnia in the palliative care setting. Seventy-four patients completed the questionnaire. Fifty-two (70%) patients had insomnia symptoms. Uncontrolled physical symptoms, most often pain (15 patients), were the commonest cause of insomnia, cited by 31 (60%) sleep-disturbed patients. Thirteen (62%) of 21 patients who had been prescribed hypnotic medication reported an improvement with the prescribed medication. Twenty (38%) of the 52 patients with insomnia suggested that improved symptom control would improve their sleep, and only two (4%) suggested the need for more hypnotic medication. We conclude that insomnia is a common symptom in terminally ill patients and that improved symptom control should be a priority in the management of insomnia in this group of patients.
Cystic sebaceous tumors (CST) are well-circumscribed, large, deeply located dermal sebaceous proliferations with a cystic growth pattern. We identified 12 CST in 8 of 19 patients with Muir-Torre syndrome (MTS). We interpret CST as a tumor spectrum with clearly benign cystic sebaceous adenomas at one end and proliferative atypical cystic sebaceous tumors at the other. When examining these proliferative atypical tumors on morphologic criteria alone, the possibility of an evolving cystic sebaceous carcinoma cannot be excluded. We have not observed recurrences or metastases, indicating that these lesions are not highly malignant carcinomas. In 10 of 12 cases of CST, we examined microsatellite instability (MSI). All 10 examined examples of CST from patients with MTS showed MSI characteristic for hereditary nonpolyposis colorectal cancer (HNPCC), which is caused by autosomal dominant inherited DNA mismatch repair (MMR) defects. Mutational analysis of the MMR genes hMSH2 and hMLH1 had revealed different germline mutations in the hMSH2 gene in three of six examined patients with MTS with CST. We then found four more CST in patients without a history of internal malignancy. All four CST exhibited MSI. By mutational analysis in one of these patients we identified a truncating germline mutation in the MMR gene hMLH1. We conclude that CST is a marker for the mismatch repair-deficient subtype of MTS with a high risk for later internal malignancies. By recognizing CST, the histopathologist can suggest the great likelihood of MTS to the clinician.
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