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1.
Brain metastases are a major cause of melanoma-related mortality and morbidity. We undertook whole-exome sequencing of 50 tumours from patients undergoing surgical resection of brain metastases presenting as the first site of visceral disease spread and validated our findings in an independent dataset of 18 patients. Brain metastases had a similar driver mutational landscape to cutaneous melanomas in TCGA. However, KRAS was the most significantly enriched driver gene, with 4/50 (8%) of brain metastases harbouring non-synonymous mutations. Hotspot KRAS mutations were mutually exclusive from BRAFV600, NRAS and HRAS mutations and were associated with a reduced overall survival from the resection of brain metastases (HR 10.01, p = 0.001). Mutations in KRAS were clonal and concordant with extracranial disease, suggesting that these mutations are likely present within the primary. Our analyses suggest that KRAS mutations could help identify patients with primary melanoma at higher risk of brain metastases who may benefit from more intensive, protracted surveillance.Subject terms: CNS cancer, Metastasis, Melanoma, Tumour biomarkers, Cancer  相似文献   
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This phase II study is the first prospective evaluation of bortezomib-dexamethasone as second-line therapy for relapsed/refractory multiple myeloma. A total of 163 patients were enrolled to receive four cycles of bortezomib-dexamethasone. Patients were investigator-assessed for response at cycle 5 Day 1, then treated as follows: responding patients received another four cycles of bortezomib-dexamethasone, while patients with stable disease were subsequently randomized to sequential treatment with a further four cycles of bortezomib-dexamethasone alone or with added cyclophosphamide or lenalidomide. The primary end point was response to sequential therapy; however, this could not be evaluated because investigator-assessed response rates to bortezomib-dexamethasone after four cycles were high, and an insufficient number of patients were randomized to sequential treatment per protocol. Among all 163 patients, validated best confirmed response rate was 66%, including 37% complete/very good partial responses; median response duration was 9.7 months. After a median follow up of 16.9 months, median time to progression and progression-free survival were 9.5 and 8.6 months, respectively; estimated 1-year overall survival was 81%. Median glomerular filtration rate improved from baseline during treatment. Among 58 patients with baseline glomerular filtration rate below 50 mL/min, 24 had renal responses. Grade 3/4 adverse events included: thrombocytopenia (17%), anemia (10%), constipation (6%), peripheral sensory neuropathy (5%), and polyneuropathy (5%). Overall, 57% of neuropathy events improved/resolved; median time to improvement was 2.1 months. These findings suggest bortezomib-dexamethasone represents an active, feasible second-line treatment option for patients with relapsed/refractory myeloma.  相似文献   
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Caffeine consumption may cause headache, particularly migraine. Its withdrawal also produces headaches and may be related to weekend migraine attacks. Transcranial Doppler sonography (TCD) has shown changes in cerebral blood flow velocities, (BFV) during and between attacks of migraine. In order to examine whether headache and changes in BFV could develop from controlled caffeine alterations, 20 healthy volunteers, without a headache history, underwent clinical evaluation, TCD and serum caffeine measurements on four occasions, comparing conditions of regular caffeine intake, caffeine withdrawal and "re-caffeination". After 24 h of complete caffeine abstinence, 10 suffered from moderate to severe headaches with complete recovery within 1 h after caffeine intake. The BFVs in both middle cerebral, both posterior cerebral and basilar arteries were higher following the withdrawal period, reaching statistical significance in the left middle cerebral, basilar and both posterior cerebral arteries. BFVs decreased significantly within half an hour after caffeine intake in all subjects, and were similar to baseline values after 2 h. Our results emphasize the relationship between caffeine withdrawal, the development of headache and alterations in cerebral blood flow velocities. Also, these findings indicate that accurate interpretation of TCD measurements should account for the influence of caffeine on BFVs.  相似文献   
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