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1.
The purpose of this study was to evaluate the ability of MRI to identify a primary site of malignancy in the breast of patients who present clinically with ipsilateral lymph nodes containing metastatic carcinoma but whose physical and mammographic examination are negative. MRI of the breast was performed on four patients using a variety of imaging parameters, all with and without gadolinium contrast. All patients had biopsy-proven adenocarcinoma of the ipsilateral axilla, with negative physical and mammographic examinations. Foci of enhancement assessed visually on precontrast and postcontrast scans (n = 1) and on substraction studies (n = 3) were considered suspicious under the clinical circumstances defined for this study. Lesions identified on MRI were re-identified on ultrasound examination and either preoperative localization for excisional biopsy or tissue sampling was performed. Surgery was performed and histopathologic correlation was obtained in all cases. Primary sites of breast carcinoma were identified in all four patients, with multiple sites of malignancy identified in three of four patients. Breast conservation therapy was made possible for three of four patients based on the results of the MRI study showing sites of malignancy and no features of cancer elsewhere in the breast. Follow-up data of 1, 2, and 5 years of these patients show no evidence of recurrent disease. MRI of the breast is a useful technique for identifying primary sites of malignancy in patients presenting with ipsilateral lymph nodes positive for metastatic adenocarcinoma when the physical and mammographic examinations are negative.  相似文献   
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Key words  axillary - block  相似文献   
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It has been believed that the primary arterial trunk of the mammalian forelimb is derived from the 7th intersegmental artery. Here we examined the early morphogenesis of the arteries and nerves in the forelimb region by adopting a method that combined intravascular dye-injection with nerve staining to whole mounted rat embryos. The study was carried out on greater numbers of specimens at smaller intervals of embryonic stages and from earlier stages than those in previous reports. We report that: (1) The multiple primary arterial trunks in the forelimb region (primary subclavians) originate directly from the lateral surface of the dorsal aorta independently of the intersegmental arteries, previous to the formation of limb buds. (2) The tips of the 8th (and the 9th) primary subclavians that originate from the aorta near the origin of the 8th (or the 9th) intersegmental artery bend cranially and/or caudally. With the formation of limb bud, they extend to form the longitudinal trunks in the presumptive axillary region. The primary arteries in the free arm region branch off from this longitudinal trunk, and one of them develops into the axial artery. (3) The origins of the primary subclavians shift their positions on the surface of the dorsal aorta and approach the origins of the neighboring intersegmental arteries to join them, and then replace the latter. Consequently, the primary subclavians appear to be ”the lateral branches of the in tersegmental arteries.” (4) The 8th primary subclavian is dominant at first, but is replaced by the 7th primary subclavian, which develops into the definitive subclavian artery. (5) With the brachial nerve plexus formation, the axillary arterial plexus derived from the longitudinal trunk develops to form two stems of the axillary artery. Accepted: 15 April 1999  相似文献   
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目的:探讨早期乳腺癌腋淋巴结转移(ALNM)的相关因素,并对阴性腋淋巴结行角蛋白19(CK19)检测以发现微转移癌.方法:收集乳腺癌病例138例,建立数据库,用Logistic回归进行单因素和多因素分析,并对有意义的指标进行相关分析,对40例患者441枚阴性腋淋巴结再切片,用CK19行免疫组织化学染色.结果:多因素分析显示肿瘤大小、肿瘤部位、癌抗原153(CA153)、人类表皮生长因子受体-2(HER2)4个指标进入Logistic回归方程,40例患者中有3例患者的腋窝淋巴结CK19免疫组织化学染色阳性.结论:肿瘤大小、肿瘤部位、CA153和HER2为乳腺癌患者ALNM的高危因素;CK19免疫组织化学染色可发现乳腺癌腋淋巴结微转移癌.  相似文献   
6.
目的 探讨前哨淋巴结活检术(SLNB)替代腋窝淋巴结清扫术(ALND)在早期乳腺癌患者治疗中的应用价值和安全性.方法 应用亚甲蓝行SLNB,2004年1月~2008年1月收治入院的临床T1-2NoM0乳腺癌患者100例入选本研究,所有患者均签署知情同意书,不同意SLNB替代ALND治疗的50例患者为A组,同意SLNB替代ALND治疗的50例患者为B组.依据前哨淋巴结(SLN)状况,对SLN阴性者仅行SLNB,SLN阳性者行AL-ND,比较分析两组间术后并发症和术后生存率的状况.结果 B组术后1、3年生存率分别为100%(100/100)、100%(100/100),A组术后1、3年生存率分别为100%(100/100)、82% (82/100),两组3年生存率比较差异有统计学意义(P<0.05);B组并发症发生率明显低于A组,两组比较差异有统计学意义(P<0.05).结论 SLNB可以指导临床开展缩小腋区淋巴清扫范围的手术,从而有效减轻手术创伤和术后并发症.早期乳腺癌手术中SLNB对术中指导乳腺癌手术范围有较大价值.  相似文献   
7.
Temperature estimation in proton resonance frequency (PRF) shift MR thermometry requires a reference, or pretreatment, phase image that is subtracted from image phase during thermal treatment to yield a phase difference image proportional to temperature change. Referenceless thermometry methods derive a reference phase image from the treatment image itself by assuming that in the absence of a hot spot, the image phase can be accurately represented in a smooth (usually low order polynomial) basis. By masking the hot spot out of a least squares (?2) regression, the reference phase image's coefficients on the polynomial basis are estimated and a reference image is derived by evaluating the polynomial inside the hot spot area. Referenceless methods are therefore insensitive to motion and bulk main field shifts, however, currently these methods require user interaction or sophisticated tracking to ensure that the hot spot is masked out of the polynomial regression. This article introduces an approach to reference PRF shift thermometry that uses reweighted ?1 regression, a form of robust regression, to obtain background phase coefficients without hot spot tracking and masking. The method is compared to conventional referenceless thermometry, and demonstrated experimentally in monitoring HIFU heating in a phantom and canine prostate, as well as in a healthy human liver. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
8.
Aimslymphadenopathy can occur after COVID-19 vaccination and when encountered at ultrasound examinations performed for other reasons might pose a diagnostic challenge. Purpose of the study was to evaluate the incidence, course and ultrasound imaging features of vaccine-induced lymphadenopathy.Methods89 healthy volunteers (median age 30, 76 females) were prospectively enrolled. Vaccine-related clinical side effects (e.g., fever, fatigue, palpable or painful lymphadenopathy) were recorded. Participants underwent bilateral axillary, supraclavicular and cervical lymph node stations ultrasound 1–4 weeks after the second dose and then again after 4–12 weeks in those who showed lymphadenopathy at the first ultrasound. B-mode, color-Doppler assessment, and shear-wave elastography (SWE) evaluation were performed. The correlation between lymphadenopathy and vaccine-related side effects was assessed using the Fisher’s exact test.ResultsPost-vaccine lymphadenopathy were found in 69/89 (78%) participants (37 single and 32 multiple lymphadenopathy). Among them, 60 presented vaccine-related side effects, but no statistically significant difference was observed between post-vaccine side effect and lymphadenopathy. Ultrasound features of vaccine-related lymphadenopathy consisted of absence of fatty hilum, round shape and diffuse or asymmetric cortical thickness (median cortical thickness of 5 mm). Vascular signal was mainly found to be increased, localized in both central and peripheral regions. SWE showed a soft cortical consistence in all cases (median value 11 Kpa). At follow-up, lymph-node morphology was completely restored in most cases (54/69, 78%) and in no case lymphadenopathy had worsened.ConclusionA high incidence of vaccine-induced lymphadenopathy was found in a population of healthy subjects, with nearly complete regression within 4–12 weeks.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40477-022-00674-3.  相似文献   
9.
乳腺癌根治术中保留肋间臂神经的临床价值分析   总被引:1,自引:0,他引:1  
李光云  王平  田景中  朱永 《淮海医药》2013,31(5):384-386
目的探讨乳腺癌手术中保留肋间臂神经的临床价值。方法对我院2007年1月~2009年12月32例保留肋间臂神经(保留组)和35例切除肋间臂神经(切除组)的乳腺癌患者进行观察并随访。结果保留组及切除组术后1、3、6、12个月患侧上臂内侧感觉障碍发生率分别为18.8%、71.4%、9.3%、54.3%与6.3%、60.0%、3.1%、37.1%,差异均有统计学意义(P值均小于0.01);手术时间及淋巴结清扫数差异无显著性;术后随访1~4年无局部复发。结论乳腺癌患者保留肋间臂神经可以明显减少术后患侧上肢感觉障碍和疼痛的发生,从而提高患者的生活质量。  相似文献   
10.
Background In breast cancer treatment, intraoperative sentinel lymph node (SLN) evaluation is used to identify patients who may potentially benefit from immediate completion of axillary lymph node dissection. Methods Prospectively collected breast cancer registry data identified 516 SLN biopsies between January 2003 and December 2005. Intraoperative evaluation (IE) of the SLNs was performed in 479 axillae. Final pathology by hematoxylin and eosin and, for negative nodes, by immunohistochemical stains was compared with the IE result. The effect of IE and final pathology on surgical treatment was examined. Results The sensitivities for IE of N0(i+) (n = 39), N1mi (n = 41), and N1a–3a (n = 89) metastases were 0%, 5%, and 63%, respectively. The specificity was 99.7%. IE identified 57 (44%) of SLN-positive (N1mi and N1a–3a) axillae, thus resulting in synchronous axillary lymph node dissection for those patients. Reoperation for false-negative IEs (N1mi or N1a–3a with negative IE) occurred in only 27 axillae (39%). Conclusions IE of SLNs has adequate sensitivity and excellent specificity. In addition to allowing patients to benefit from synchronous surgery, IE helped patients to receive care in concordance with recommended practice guidelines. The false-negative IE of SLNs highlights uncertainty with the clinical significance of axillary nodal staging when only small amounts of metastatic disease are identified in the axilla.  相似文献   
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