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61.
目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.  相似文献   
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63.

Background:

Mutations in the Kirsten Ras (KRAS) oncogene are common in colorectal cancer (CRC). The role of KRAS-mutation status as a prognostic factor, however, is unclear. We evaluated the relationship between KRAS-mutation status and CRC survival, considering heterogeneity in this association by tumour and patient characteristics.

Methods:

The population-based study included individuals diagnosed with CRC between 1998–2007 in Western Washington State. Tumour specimens were tested for KRAS exon 2 mutations, the BRAF p.V600E mutation, and microsatellite instability (MSI). We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between KRAS-mutation status and disease-specific and overall survival. Stratified analyses were conducted by age, sex, tumour site, stage, and MSI. We conducted additional analyses combining KRAS-mutation, BRAF-mutation, and MSI status.

Results:

Among 1989 cases, 31% had KRAS-mutated CRC. Kirsten Ras (KRAS)-mutated CRC was associated with poorer disease-specific survival (HR=1.37, 95% CI: 1.13–1.66). This association was not evident in cases who presented with distant-stage CRC. Cases with KRAS-wild-type/BRAF-wild-type/MSI-high CRC had the most favourable prognosis; those with CRC exhibiting a KRAS- or BRAF-mutation and no MSI had the poorest prognosis. Patterns were similar for overall survival.

Conclusion:

Kirsten Ras (KRAS)-mutated CRC was associated with statistically significantly poorer survival after diagnosis than KRAS-wild-type CRC.  相似文献   
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65.
Epithelioid glioblastomas are one of the rarest histological variants of glioblastomas, which are not formally recognized by the World Health Organization (WHO) classification. Epithelioid glioblastomas usually occur as primary lesions, but there have been several reports of secondary epithelioid glioblastomas or epithelioid glioblastomas with pre‐ or co‐existing lesions to date. The serine/threonine‐protein kinase B‐Raf (BRAF) V600E mutation has been found at a high frequency of 54% in epithelioid glioblastomas. We present a case of a 26‐year‐old female patient with an epithelioid glioblastoma with the BRAF V600E mutation in her right frontal lobe. In the present case, a low‐grade diffuse astrocytoma component had colocalized with the epithelioid glioblastoma. The component presented prominent calcification on neuroimages as well as by histology, and low‐grade diffuse astrocytoma was considered to be a precursor lesion of an epithelioid glioblastoma. However, the BRAF V600E mutation was detected only in epithelioid glioblastoma but not in low‐grade diffuse astrocytoma. To the best of our knowledge, this is the first report demonstrating a discrepancy in the BRAF V600E mutation states between epithelioid glioblastoma and colocalized low‐grade astrocytoma.  相似文献   
66.

Introduction

The BRAF V600E mutation in papillary thyroid cancer (PTC) has been associated with resistance to 131I. Our aim was to quantify the response to 131I after surgery in patients who had the mutation (BRAF+) and those who did not have the mutated gene (BRAF?).

Method

A prospective cohort study was designed, from September 2015 to February 2016, which included patients with PTC receiving therapy after surgical treatment. Variables were described for age, gender, histology, tumor stage, thyroglobulin values before, 48 h after and 6 months after 131I; absorbed dose and % activity on days 2 and 7 and elimination time.

Results

41 patients giving in total 67 thyroid remnants were included. 61% were BRAF+. In stages iii and iv, 80% were BRAF+. In lateral resection, 100% were BRAF+. The number of nodes was higher in BRAF+: 3.4 vs 1.2 (P = .01). The classic variant was predominant in BRAF+ (91.7% vs 8.3%, P = .03). 85.7% vs 14.3% of BRAF+ had desmoplastic reaction (P = .02). The BRAF+ had a lower absorbed dose than the administered activity (5.4 Gy/MBq vs 20 Gy/MBq, P = .02); lower% activity with respect to the unit of mass at 2 (0.046%/g vs 0.103%/g, P = .02) and at 7 days (0.006%/gr vs 0.034%/gr, P = .04)

Conclusions

The mutation of the BRAF V600E gene is related with greater resistance to postoperative treatment with 131I since the onset of the disease.  相似文献   
67.
68.
ABSTRACT

Introduction

Molecular profiling has led to significantly longer survival in metastatic colorectal cancer (mCRC) patients. Clinical guidelines recommend testing for KRAS/NRAS, BRAF and MSI status, and new biomarkers such as HER2 amplification and NTRK fusions have emerged more recently in refractory CRC, supported by overwhelming clinical relevance. These biomarkers can guide treatment management to improve clinical outcomes in these patients.  相似文献   
69.
目的:探讨超声造影(CEUS)及BRAF基因突变在甲状腺乳头状癌(PTC)被膜外侵犯术前诊断中的价值。 方法:入组119名患者共129个PTC病灶,其中25个经术后病理证实存在甲状腺被膜外侵犯。记录传统超声(US)及CEUS模式下PTC与被膜接触范围、是否出现被膜中断现象,以及患者BRAF基因突变检测结果。计算上述特征单独及联合诊断PTC被膜外侵犯的效能。 结果:被膜外侵犯组BRAF基因突变阳性率、US及CEUS被膜接触范围及被膜中断率均显著高于无侵犯组(P<0.05)。接触范围中,US及CEUS均以?25%为界值诊断被膜外侵犯准确度最高。在各超声特征单独及联合BRAF基因突变用于诊断时,CEUS准确度均高于US,CEUS联合BRAF准确度88.38%。 结论:PTC被膜外侵犯临床、超声特征包括:BRAF基因突变阳性、US及CEUS显示结节与被膜接触?25%及被膜中断。CEUS诊断准确度高于US。CEUS联合BRAF基因突变在术前诊断PTC被膜外侵犯中具有重要意义。  相似文献   
70.
目的: 探讨BRAF基因突变与甲状腺乳头状癌的相关性。方法: 采用PCR和测序技术,对73例散发的甲状腺乳头状癌患者和16例甲状腺瘤患者组织BRAF基因突变进行筛查。结果: 甲状腺乳头状癌组中42例存在突变;而在甲状腺瘤组中未发现突变。BRAF突变与甲状腺乳头状癌的淋巴转移以及临床分期间比较,差异有统计学意义(P<0.05)。结论: BRAF基因突变与甲状腺乳头状癌发生及其淋巴结转移、临床分期相关。  相似文献   
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