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101.
OBJECTIVE: The authors determined whether microscopically positive surgical margins are detrimental to the outcome of early stage breast cancer patients treated with conservation surgery and radiation therapy. SUMMARY BACKGROUND DATA: The optimal extent of breast surgery required for patients treated with conservation surgery and radiation therapy has not been established. To achieve breast preservation with good cosmesis, it is desirable to resect as little normal tissue as possible. However, it is critical that the resection does not leave behind a tumor burden that cannot be adequately managed by moderate doses of radiation. It is not known whether microscopically positive surgical margins are detrimental to patient outcome. METHODS: The records of 259 consecutive women (262 breasts) treated with local excision (complete removal of gross tumor with a margin) and axillary dissection followed by radiation therapy for clinical stage I and II infiltrating ductal breast cancer at Duke University Medical Center and the University of North Carolina between 1983 and 1988 were reviewed. Surgical margins were considered positive if tumor extended to the inked margins; otherwise the margins were considered negative. Margins that could not be determined, either because the original pathology report did not comment on margins, or because the original specimen had not been inked were called indeterminate. RESULTS: Of the 262 tumors, 32 (12%) had positive margins, 132 (50%) had negative margins, and the remaining 98 (38%) had indeterminate margins. There were 11 (4%) local failures; 3/32 (9%) from the positive margin group, 2/132 (1.5%) from the negative margin group, and 6/98 (6%) from the indeterminate group. The actuarial local failure rates at 5 years were 10%, 2%, and 10%, respectively, p = 0.014 positive vs. negative, p = 0.08 positive vs. indeterminate (log rank test). Margin status had no impact on survival or freedom from distant metastasis; 63 patients who originally had positive or indeterminate margins were re-excised. Two of 7 with positive margins after re-excision versus 1/56 rendered margin negative had a local recurrence. CONCLUSIONS: The authors recommend re-excision for patients with positive margins because of improved local control of those rendered margin negative and identification of those patients at high risk for local failure (those who remain positive after re-excision). Because margin status impacts on local control, tumor margins after conservation surgery should be accurately determined in all patients.  相似文献   
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N J Buckley  W M Burch  G S Leight 《Surgery》1986,100(5):932-937
Teratomas in the neck are rare neoplasms. Most occur in the neonate and are benign. In contrast, cervical teratomas in adults are malignant and carry a poor prognosis. Fourteen adult cases have been reported in the world literature, and 11 of these were stated to have arisen in the thyroid gland. A case of a 27-year-old man who presented with a large goiter is reported. A preoperative diagnosis of a malignant thyroid mass was suggested by clinical examination, needle aspiration, and computerized tomography. The patient had a subtotal debulking thyroidectomy. The pathologic specimen confirmed a primary malignant teratoma of the thyroid gland. Despite a combination of radiotherapy and chemotherapy, which were well tolerated, the patient died 2 months after surgery.  相似文献   
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There is currently substantial clinical interest in growth hormone (GH) as a protective agent against radiation-related normal tissue injury. To further assess the potential radiation injury-preventive effects of GH, these effects were studied in rats by using a radiation-induced skin injury model. Group 1 received neither GH nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (radiation group). Group 3 and 4 received the same irradiation plus either 0.01 U/kg/day GH (RT + 0.01 GH group) or 0.02 U/kg/day GH (RT + 0.02 GH group) subcutaneously. Clinically and histopathologically, acute skin reactions were assessed by two independent experts in radiation oncology and pathology, respectively. Irradiation increased dermatitis in rats when compared with the control group. The severity of radiodermatitis in the rats in the RT + 0.01 GH and RT + 0.02 GH groups was significantly lower than that in the RT group; radiodermatitis developed earlier in the RT group than in the other groups. GH was efficacious in preventing epidermal atrophy, dermal degeneration such as oedema and collagen fibre loss, and hair follicle atrophy, but not better than in the control group. These results are preliminary to studies that will be performed with higher doses of GH in radiation-treated cancer patients, with the aim of reducing radiation-induced toxicity.  相似文献   
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人白血病HL60细胞的分化状态对细胞凋亡的影响   总被引:2,自引:0,他引:2  
用细胞培养和流式细胞术等方法,研究人白血病HL60细胞诱导分化后,对三尖杉酯碱(Har)和喜树碱(Cam)诱导细胞凋亡的影响。结果表明,12-豆蔻酰及13-乙酸佛波酯以16nmol·L-1浓度处理HL60细胞24h,细胞向单核/巨噬细胞方向分化,阻断于G1期;分化细胞抗Har和Cam诱导的细胞凋亡,但其c-myc基因的表达无变化。1.4%二甲基亚砜处理HL60细胞48h,细胞向粒细胞方向分化,阻断于G1期;分化细胞抗Cam,而不抗Har诱导的细胞凋亡;分化细胞的c-myc基因表达明显下降。结果提示,人白血病HL60细胞的分化状态,明显影响三尖杉酯碱和喜树碱诱导的细胞凋亡,但可能与c-myc基因的表达变化无关。  相似文献   
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目的探索内镜下经扩大鼻蝶入路显露斜坡区的可行性,为切除斜坡区病变提供解剖学参考。方法在10例成人头部固定标本上,内镜下模拟扩大经鼻蝶手术入路显露斜坡区,观察有关显微解剖标志。结果扩大经鼻蝶内镜入路可磨除从鞍后到斜坡、枕骨大孔前缘的骨性结构;可显露斜坡区腹侧硬膜下的椎基底动脉及其分支、后交通动脉及其与大脑后动脉汇合处、动眼神经、脑干腹侧等结构。此入路的手术标志主要包括:蝶筛隐窝、蝶窦开口、视神经隆突、颈内动脉隆突与颈内动脉视神经隐窝、咽结节、枕骨大孔前缘。结论内镜下扩大经鼻蝶手术入路可充分显露鞍后-斜坡区的腹侧硬膜下结构,适用于此区病变的手术治疗。  相似文献   
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