Juvenile nasopharyngeal angiofibromas (JNAs) are locally aggressive vascular tumors occurring predominantly in adolescent males. The pathogenesis of JNAs is unknown. Recently, JNAs have been reported to occur at incre...
详细信息
Juvenile nasopharyngeal angiofibromas (JNAs) are locally aggressive vascular tumors occurring predominantly in adolescent males. The pathogenesis of JNAs is unknown. Recently, JNAs have been reported to occur at increased frequency among patients with familial adenomatous polyposis, suggesting that alterations of the adenomatous polyposis coli (APC)/beta -catenin pathway might also be involved in the pathogenesis of sporadic JNAs, We analyzed somatic beta -catenin and APC gene mutations in 16 sporadic JNAs from nonfamilial adenomatous polyposis patients using immunohistochemistry for beta -catenin, and direct DNA sequencing for exon 3 of the beta -catenin gene and the mutation cluster region of the APC gene. Nuclear accumulation of beta -catenin was diffusely present in the stromal cells but not in the endothelial cells of all 16 JNAs, Activating beta -catenin gene mutations were present in 75% (12 of 16) of JNAs, Six JNA patients also had recurrent tumors after surgery, and in all cases the beta -catenin gene status of the recurrent JNA was identical to the initial tumor. No mutations in the mutation cluster region of the APC gene were detected in the four JNAs without beta -catenin mutations. The high frequency of beta -catenin mutations in sporadic JNAs and the presence of identical beta -catenin gene mutations in recurrent tumors indicates that activating beta -catenin gene mutations are important in the pathogenesis of JNAs. The immunohistochemical localization of beta -catenin only to the nuclei of stromal cells further suggests that the stromal cells, rather than endothelial cells, are the neoplastic cells of JNAs.
We report 6 cases of patients with tuberous sclerosis and concomitant dental pathosis. The multiple manifestations in tuberous sclerosis determine its impact on dental therapy. A lack of awareness of this condition ma...
详细信息
We report 6 cases of patients with tuberous sclerosis and concomitant dental pathosis. The multiple manifestations in tuberous sclerosis determine its impact on dental therapy. A lack of awareness of this condition may compound the possible side effects of dental treatment. Possible preventive measures by dentists are highlighted in this presentation. Medical evaluation and the control of risk factors in relation to general anesthesia and sedation are key considerations for the management of patients with tuberous sclerosis.
PURPOSE: To report a patient who had concomitant combined hamartoma of the retinal pigment epithelium and retina and juvenile nasopharyngeal angiofibroma. METHOD: Case report. RESULTS: An 18-year-old man presented wit...
详细信息
PURPOSE: To report a patient who had concomitant combined hamartoma of the retinal pigment epithelium and retina and juvenile nasopharyngeal angiofibroma. METHOD: Case report. RESULTS: An 18-year-old man presented with a juvenile nasopharyngeal angiofibroma and a combined hamartoma of the retina and retinal pigment epithelium in the ipsilateral eye. The diagnosis of juvenile nasopharyngeal angiofibroma was confirmed by histopathology, and the diagnosis of combined hamartoma was established by typical ophthalmoscopic and fluorescein angiographic findings. CONCLUSION: Juvenile nasopharyngeal angiofibroma may be associated with combined hamartoma of the retina and retinal pigment epithelium. (Am J Ophthalmol 2001;132:131-132. (C) 2001 by Elsevier Science Inc. All rights reserved.).
Giant cell angiofibroma, a recently proposed new clinicopathological entity, arises exclusively in the orbit in adults and histologically exhibits features intermediate between those of giant cell fibroblastoma and so...
详细信息
Giant cell angiofibroma, a recently proposed new clinicopathological entity, arises exclusively in the orbit in adults and histologically exhibits features intermediate between those of giant cell fibroblastoma and solitary fibrous tumor. In a typical case of giant cell angiofibroma, abnormalities of chromosome 6 with a common pattern involving 6q13 were detected together with various other chromosomal aberrations. To our knowledge, this is the first reported case of giant cell angiofibroma demonstrating chromosomal abnormalities. (C) 1999 Elsevier Science Inc., 1999. All rights reserved.
暂无评论