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目前临床上有许多怀疑前列腺癌但穿刺阴性的病例,为了避免漏诊,多数患者必须接受重复穿刺。尽管部分患者经重复穿刺确诊为前列腺癌,而更多患者经过长期随访以及反复穿刺最终确诊为良性病变。近期研究证实,癌灶附近的组织学表现正常的组织中也可发生与癌灶相似的分子改变。因此,我们认为在前列腺癌的发生过程中存在区域效应。在这一理论指导下,选择适当的可反映前列腺癌区域效应的标记物,在穿刺阴性的标本中检出与癌灶相似的分子改变,就可以帮助临床医生在常规病理诊断之前,提前预测前列腺癌的发生。如果能够找到这样的标记物,并在大规模的诊断试验中证实其可行性,那么就可以极大地改善前列腺癌诊断的现状。  相似文献   
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目的:评估胃癌根治术同时性射频消融治疗在治疗胃癌肝转移的临床意义。方法:收集2008年1月至2010年12月19例胃癌肝转移患者,合计转移灶33个,转移灶小于4厘米,且合计不超过4个转移灶。射频消融治疗在术中超声引导下完成。Kap-lan—Meier法分析无病生存期,无肝转移生存期及总生存期。对临床病理学因子及肝转移相关因子采用Log-rank法Cox风险比例模型解析。结果:中位无病生存、无肝转移生存及总生存期为355,394及488天。有3例患者获得长期的无复发生存。单因素分析显示,较早的T分期、N分期,较少的转移灶数量,较小的转移灶直径与良好的预后相关。多因素分析提示,病灶数量与病灶直径为独立预后因子。结论:肝转移射频消融治疗安全性好,对单发的小于4cm转移灶,以及多发病灶合计直径小于4cm者射频消融治疗较为适用,可有显著生存获益。部分患者可迭临床治愈。对于胃癌肝转移的合适病例,射频消融治疗值得推广。  相似文献   
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B. Vicandi, J.A. Jiménez‐Heffernan, P. López‐Ferrer, P. González‐Peramato, M. Patrón and J.M. Viguer
Fine needle aspiration cytology of basal cell adenoma of the salivary gland: a cytohistological correlation study of 35 cases Objective: In order to evaluate the possibility of a specific cytological recognition of basal cell adenoma (BCA) we reviewed our experience with 35 histologically proven cases. Few series describing cytological features of BCA are available and diagnostic cytological criteria are not well established. Methods: This study was based on 41 cytology samples from 35 patients with BCA. Thirty‐five aspiration procedures were performed pre‐operatively and six on tumour recurrence. Nineteen of the 35 patients were men and 16 women. The mean age at diagnosis was 55 years old (range 24–92). The series includes one non‐representative case. Except for one tumour located in the upper lip, all of them involved the parotid gland. Results: Aspirates were cellular, showing groups with dense, homogeneous metachromatic stroma and single cells. Relevant features were the trident‐like configuration of groups, intimate relationship between neoplastic cells and stroma and cellular polymorphism. In approximately half of the cases a precise diagnosis was given. Most of the remaining tumours were diagnosed as benign but they were difficult to differentiate from pleomorphic adenoma. Regarding malignancy, there were two misdiagnoses of acinic cell carcinoma, due to high epithelial cellularity along with scarcity of stroma, and one case was considered to be suspicious of malignancy. Conclusion: BCA shows characteristic cytological features that allow a precise diagnosis. The main differential diagnosis is epithelial‐rich pleomorphic adenoma, while acinic cell carcinoma is a potential false positive.  相似文献   
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AimThe aim of this study was to estimate the population-level ‘cure’ of Maltese colorectal cancer patients diagnosed between 1995 and 2004, and to estimate the median survival time for the ‘uncured’ patients.Methods and study populationAnalysis was conducted on 1470 cases registered by the Malta National Cancer Register between 1995 and 2004 and followed up to end of 2010. The mean age of the patients was 66.4 (95%CI 65.8–67.1), and the number of men and women were equal. Background mortality for 1995–2010 was extracted from publicly available life tables. A mixture model with Weibull survival distribution and identity link was used to model ‘cure’.ResultsThe overall ‘cured’ proportion for the patients diagnosed in 1995–1999 was 45.3% (95%CI 40.2–50.5) while the ‘cured’ proportion for the patients diagnosed in 2000–2004 was 52.3% (95%CI 47.2–57.5). Median survival time for the ‘uncured’ patients increased in the second calendar period from 1.25 years (95%CI 1.04–1.45) to 1.42 years (95%CI 1.15–1.76).ConclusionIn Malta, as in the rest of Europe, improvements have been made in short- and long-term survival over the 15-year period under study. To continue this improvement, differences by age that still persist must be investigated and efforts focused to reduce any gaps between Malta and other European countries.  相似文献   
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盐酸洛拉曲克在体内、外对S-180细胞株的抗增殖作用   总被引:2,自引:0,他引:2  
研究合合成新型胸苷合成酶抑制剂盐酸洛拉曲克在体内、外对S-180细胞株及正常人胚肾HEK293细胞的抗增殖作用;使用MTT法测定抑制率,以提高荷腹水瘤小鼠存活时间及荷实体瘤瘤重减轻情况为指标考察盐酸洛拉曲克对S-180所致肿瘤的治疗作用。结果表明:在体外盐酸洛拉曲克对S-180肿瘤细胞株有较强的细胞毒作用,对正常细胞HEK293抑制作用较弱(P<0.05);体内实验显示盐酸洛拉曲克可明显提高荷腹水瘤小鼠的存活时间,减轻荷实体瘤小鼠的瘤重,疗效与氟尿嘧啶(10mg/kg)相当(P>0.05)或更好(P<0.05)。可见,盐酸洛拉曲克在体内、外对S-180肿瘤细胞有显著的抗增殖作用,在体外对肿瘤细胞 具有选择性的抗增殖作用。  相似文献   
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BRD7单核苷酸多态性及鼻咽癌易感性分析   总被引:7,自引:5,他引:2  
为了探讨BRD7基因的遗传变异在鼻咽癌发生的作用,采用PCR-SSCP和直接测序方法对BRD7 基因的编码区进行单核苷酸多态性(coding-region single nucleotide polymorphism, cSNP)分析,并对两个鼻咽癌家系的高危成员、57个散发性鼻咽癌病人和50个正常人进行了BRD7等位基因分型.在BRD7基因的编码区发现了3个cSNP(C450T、A538C和A737G),其中A538C颠换导致其编码蛋白的第162个氨基酸由Asp变为Ala;C450T改变与同义的A737C多态性偶联发生在87.7%的鼻咽癌活检组织和配对的外周血、所有的鼻咽癌家系的患者及8个易感成员,但是仅存在于22%的正常人血标本中.C450T多态性变化可以导致其编码蛋白在第133位氨基酸的翻译终止(G133Ter).以上结果说明,C450T和A737C偶联的多态性改变是鼻咽癌发生和发展的重要遗传易感风险因子之一(P<0.01);BRD7基因有两种翻译方式,G133Ter可以导致另一种截断的翻译本(truncated isoform).  相似文献   
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Wnt/β-catenin signaling plays an important role not only in cancer, but also in cancer stem cells. In this study, we found that β-catenin and OCT-4 was highly expressed in cisplatin (DDP) selected A549 cells. Stimulating A549 cells with lithium chloride (LiCl) resulted in accumulation of β-catenin and up-regulation of a typical Wnt target gene cyclin D1. This stimulation also significantly enhanced proliferation, clone formation, migration and drug resistance abilities in A549 cells. Moreover, the up-regulation of OCT-4, a stem cell marker, was observed through real-time PCR and Western blotting. In a reverse approach, we inhibited Wnt signaling by knocking down the expression of β-catenin using RNA interference technology. This inhibition resulted in down-regulation of the Wnt target gene cyclin D1 as well as the proliferation, clone formation, migration and drug resistance abilities. Meanwhile, the expression of OCT-4 was reduced after the inhibition of Wnt/β-catenin signaling. Taken together, our study provides strong evidence that canonical Wnt signaling plays an important role in lung cancer stem cell properties, and it also regulates OCT-4, a lung cancer stem cell marker.  相似文献   
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目的 :检测食管鳞癌中人乳头状瘤病毒 (HPV)的感染情况 ,探讨 HPV与食管癌发病的关系。方法 :用原位杂交技术及免疫组化方法对 33例食管鳞癌手术切除标本进行 HPV检测。结果 :用原位杂交方法检测食管鳞癌中 HPV DNA检出率为 4 5 .5 % (15 / 33)。HPV DNA阳性与食管鳞癌肿瘤细胞的分化程度无关 (P>0 .0 5 )。HPV衣壳蛋白的免疫组化检测均为阴性。结论 :HPV感染可能是引起食管上皮癌变的原因之一 ,与食管鳞癌的发生有关。即使在存在 HPV DNA的病例中 ,HPV衣壳蛋白亦可以不表达  相似文献   
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