MRS分析T3N0M0前列腺癌局部冷冻治疗后癌区代谢动态变化的临床研究

背景与目的:氩氦冷冻治疗(cryotherapy)已成为早期前列腺癌(prostate cancer,PCa)首选治疗方法之一,而我国尚缺乏有关前列腺癌冷冻治疗的可评价资料报道。本研究采用磁共振波谱(magneticresonance spectroscopy,MRS)定量分析前列腺癌冷冻治疗后癌区代谢的动态变化。方法:经直肠指诊、前列腺特异性抗原(prostate-specific antigen,PSA)检测及MRI、MRS检查,最后经病理活检确诊为前列腺癌患者22例,行冷冻治疗,术后定期复查PSA,根据PSA结果,如术后复查PSA>0.5 ng/mL时,1周内行MRI、MRS检查及超声引导下病理活检,如冷冻术后6、12、24个月内均无PSA升高,可分别于术后6、12、24个月分别行MRI、MRS检查和超声引导下病理穿刺活检。根据病理穿刺确诊为前列腺癌,于对应MRS代谢图上测量兴趣区的胆碱(choline,Cho)、枸橼酸盐(citrate,Cit)及(胆碱+肌酸)/枸橼酸盐[(Cho+Cre)/Cit]即CC/C代谢。结果:冷冻治疗后病理活检可见有大量坏死区,MRS未观察到Cho峰和Cit峰,或Cho峰和Cit峰持续下降。冷冻治疗后病理活检示原位复发,MRS可见有Cho峰和Cit峰,其信噪比较术前降低,而CC/C的比值变化不显著。结论:MRS分析评估PCa冷冻治疗后癌区代谢的动态变化,是无创评价冷冻术后疗效及早期诊断肿瘤复发有价值的临床方法。     

磁共振波谱成像联合弥散加权成像检查对胶质瘤术前分级的诊断价值及对术后复发的预测价值

目的 分析磁共振波谱成像（MRS）联合弥散加权成像（DWI）检查对胶质瘤术前分级的诊断价值及对术后复发的预测价值。方法 选取121例胶质瘤患者,其中低级别54例,高级别67例。所有患者均行MRS、DWI检查,且术后6个月进行复查,根据复发情况分为复发组43例与非复发组78例。比较术前不同分级胶质瘤患者及不同复发情况胶质瘤患者的MRS、DWI参数;以病理结果为金标准,分析MRS、DWI单独及联合检查对术前分级的诊断效能及对术后复发的预测效能。结果 高级别组患者表观弥散系数（ADC）、相对表观弥散系数（rADC）、N-乙酰天门冬氨酸/胆碱（NAA/Cho）、NAA/肌酸（NAA/Cr）均明显低于低级别组,Cho/Cr明显高于低级别组,差异均有统计学意义（P﹤0.01）。MRS、DWI单独及联合检查诊断胶质瘤术前分级与病理结果的一致性Kappa值分别为0.533、0.507及0.752。MRS、DWI联合检查诊断胶质瘤术前分级的灵敏度（92.59%）、特异度（91.04%）、准确度（91.74%）均高于MRS、DWI单独检查。复发组患者ADC、rADC、NAA/Cho及NAA/Cr均明显低于...     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

宫颈癌中高危型HPV E6与端粒酶的相关性

高危型人乳头瘤病毒(HPV)感染是宫颈癌的主要病因,宫颈癌细胞中端粒酶的高活性与高危型HPV感染关系密切.E6是高危型HPV主要癌基因,可激活端粒酶,促使P53降解和失活,还可引起其他抑癌基因的异常、癌基因的活化等.高危型HPV E6激活端粒酶使细胞永生化是宫颈癌发生的关键步骤.     

In vivo proton (H1) magnetic resonance spectroscopy for cervical carcinoma

Proton magnetic resonance spectroscopy (MRS) may be a useful tool in both the initial diagnosis of cervical carcinoma and the subsequent surveillance after radiation therapy, particularly when other standard diagnostic methods are inconclusive. Single voxel magnetic resonance (MR) spectral data were acquired from 8 normal volunteers, 16 patients with cervical cancer before radiation therapy, and 18 patients with cervical cancer after radiation therapy using an external pelvic coil at a 1.5-T on a Signa system. The presence or absence of various resonances within each spectrum was evaluated for similarities within each patient group and for spectral differences between groups. Resonances corresponding to lipid and creatine dominated the spectrum for the eight normal volunteers without detection of a choline resonance. Spectra from 16 pretreatment patients with biopsy-proven cervical cancer revealed strong resonances at a chemical shift of 3.25 ppm corresponding to choline. Data acquired from the 18 posttreatment setting studies was variable, but often correlated well with the clinical findings. Biopsy confirmation was obtained in seven patients. H1 MRS of the cervix using a noninvasive pelvic coil consistently demonstrates reproducible spectral differences between normal and neoplastic cervical tissue in vivo. However, signal is still poor for minimal disease recurrence. Further study is needed at intervals before, during, and after definitive irradiation with biopsy confirmation to validate the accuracy of MRS in distinguishing persistence or recurrence of disease from necrosis and fibrosis.     

Choline metabolism in malignant transformation

Abnormal choline metabolism is emerging as a metabolic hallmark that is associated with oncogenesis and tumour progression. Following transformation, the modulation of enzymes that control anabolic and catabolic pathways causes increased levels of choline-containing precursors and breakdown products of membrane phospholipids. These increased levels are associated with proliferation, and recent studies emphasize the complex reciprocal interactions between oncogenic signalling and choline metabolism. Because choline-containing compounds are detected by non-invasive magnetic resonance spectroscopy (MRS), increased levels of these compounds provide a non-invasive biomarker of transformation, staging and response to therapy. Furthermore, enzymes of choline metabolism, such as choline kinase, present novel targets for image-guided cancer therapy.     

RNA interference-mediated choline kinase suppression in breast cancer cells induces differentiation and reduces proliferation

Choline kinase is overexpressed in breast cancer cells and activated by oncogenes and mitogenic signals, making it a potential target for cancer therapy. Here, we have examined, for the first time, the effects of RNA interference (RNAi)-mediated down-regulation of choline kinase in nonmalignant and malignant human breast epithelial cell lines using magnetic resonance spectroscopy (MRS) as well as molecular analyses of proliferation and differentiation markers. RNAi knockdown of choline kinase reduced proliferation, as detected by proliferating cell nuclear antigen and Ki-67 expression, and promoted differentiation, as detected by cytosolic lipid droplet formation and expression of galectin-3. The functional importance of RNAi-mediated choline kinase down-regulation on choline phospholipid metabolism was confirmed by the significant reduction of phosphocholine detected by MRS. These results strongly support the targeting of choline kinase in breast cancer cells with RNAi and show the potential ability of noninvasive MRS to detect and evaluate future treatments incorporating such strategies.     

磁共振氢质子波谱在乳腺肿瘤诊断中的临床应用

Proton magnetic resonance spectroscopy(1H MRS)can provide specific biochemical information within breast lesions and the elevated composite choline concentration as a useful diagnostic tool has been used to distinguish malignant from benign breast lesions,early evaluate response to therapy and predict prognosis.However,several obstacles including poor spatial resolution,low signal-to-noise ratio(SNR),long acquisition time and the difficulty of"extra"lipid suppression may have a negative impact on the routine application of in vivo 1H MRS for human breast cancer.At present,optimization H MRS methodology for breast studies has been performed.     

Clinical value of proton magnetic resonance spectroscopy for differentiating recurrent or residual brain tumor from delayed cerebral necrosis

: Delayed cerebral necrosis (DN) is a significant risk for brain tumor patients treated with high-dose irradiation. Although differentiating DN from tumor progression is an important clinical question, the distinction cannot be made reliably by conventional imaging techniques. We undertook a pilot study to assess the ability of proton magnetic resonance spectroscopy (¹H MRS) to differentiate prospectively between DN or recurrent/residual tumor in a series of children treated for primary brain tumors with high-dose irradiation.

: Twelve children (ages 3–16 years), who had clinical and MR imaging (MRI) changes that suggested a diagnosis of either DN or progressive/recurrent brain tumor, underwent localized ¹H MRS prior to planned biopsy, resection, or other confirmatory histological procedure. Prospective ¹H MRS interpretations were based on comparison of spectral peak patterns and quantitative peak area values from normalized spectra: a marked depression of the intracellular metabolite peaks from choline, creatine, and N-acetyl compounds was hypothesized to indicate DN, and median-to-high choline with easily visible creatine metabolite peaks was labeled progressive/recurrent tumor. Subsequent histological studies identified the brain lesion as DN or recurrent/residual tumor.

: The patient series included five cases of DN and seven recurrent/residual tumor cases, based on histology, The MRS criteria prospectively identified five out of seven patients with active tumor, and four out of five patients with histologically proven DN correctly. Discriminant analysis suggested that the primary diagnostic information for differentiating DN from tumor lay in the normalized MRS peak areas for choline and creatine compounds.

: Magnetic resonance spectroscopy shows promising sensitivity and selectivity for differentiating DN from recurrent/progressive brain tumor. A novel diagnostic index based on peak areas for choline and creatine compounds may provide a simple discriminant for differentiating DN from recurrent or residual primary brain tumors.     

The evaluation of human breast lesions with magnetic resonance imaging and proton magnetic resonance spectroscopy

Purpose. MR spectroscopy (MRS) assists in lesion characterization and diagnosis when combined with magnetic resonance imaging (MRI). Cancerous lesions demonstrate elevated composite choline levels arising from increased cellular proliferation. Our study investigated if MR spectroscopy of the breast would be useful for characterizing benign and malignant lesions. Materials and methods. Single voxel proton MR spectroscopy (MRS) was acquired as part of an MR imaging protocol in 38 patients referred upon surgical consultation. The MR spectra were read independently in a blinded fashion without the MR images by three spectroscopists. The MRI exam was interpreted in two settings: (a) as a clinical exam with detailed histories and results from previous imaging studies such as mammography or ultrasound included and (b) as a blinded study without prior histories or imaging results. Results. Elevated choline levels were demonstrated by MRS in 19 of the 23 confirmed cancer patients. The sensitivity and specificity for determining malignancy from benign breast disease with MRS alone were 83 and 87%, respectively, while a blinded MRI review reported 95 and 86%, respectively. Conclusions. Proton MR spectroscopy provides a noninvasive, biochemical measure of metabolism. The technique can be performed in less than 10min as part of an MRI examination. MRI in combination with MRS may improve the specificity of breast MR and thereby, influence patient treatment options. This may be particularly true with less experienced breast MRI readers. In exams where MRI and MRS agree, the additional confidence measure provided by MRS may influence the course of treatment.     

Clinical utility of proton magnetic resonance spectroscopy in characterizing breast lesions

Proton magnetic resonance spectroscopy ((1)H MRS) of the breast has been proposed as an adjunct to the magnetic resonance imaging (MRI) examination to improve the specificity of distinguishing malignant breast tumors from benign breast tumors. In this review, we carry out a pooled analysis of the clinical breast (1)H MRS studies undertaken to date to determine the factors that influence the diagnostic performance of this method. In total, five studies of breast (1)H MRS from four independent centers around the world have been published to date. Altogether, 153 tumors were examined, 100 of which were confirmed histologically to be malignant and 53 of which were benign. The lesions presenting a detectable composite choline signal in their corresponding (1)H MR spectra were diagnosed as malignant, whereas the lesions with no choline signal were diagnosed as benign. The sensitivity and specificity of breast (1)H MRS for detecting breast cancer were 83% (95% confidence interval [CI] = 73% to 89%) and 85% (95% CI = 71% to 93%), respectively, and both values could be as high as 92% after technical exclusions. In a subgroup of 20 young women, the sensitivity and the specificity of the method approached 100%. The factors limiting the sensitivity of the examination were mainly technical. The use of the composite choline signal as a marker for malignancy in breast (1)H MRS is a robust method with highly reliable interpretation, because it is based on the appearance of a single peak. The method is likely to provide even better results with technologic advances in breast MRS that lead to the improved detection of the composite choline signal.     

MR spectroscopy of prostate cancer. Initial clinical experience

Aim of the study was to evaluate the effectiveness of proton MR Spectroscopic (MRS) imaging in the detection and localization of prostate cancer, prospectively compared with histopathologic findings. Magnetic Resonance (MR) and MRS imaging were performed in 65 patients with high levels of prostate-specific antigen (PSA) and suspicious areas at the transrectal ultrasound (TRUS). At MR areas of interest were reported as normal, equivocal or suspicious. At MRS imaging, cancer was diagnosed as "possible" if the ratio of choline plus creatine to citrate exceeded 2 SDs above mean normal peripheral zone values or as "definite" if the ratio exceeded 3 SDs. All patients underwent a TRUS 10-core biopsy within 30 days of the imaging study. MR alone showed sensitivity, specificity, positive predictive values, negative predictive values and accuracy for detection of prostate cancer of 85%, 76%, 53%, 91% and 65%, respectively, whereas MRS alone showed 89%, 77%, 78%, 69% and 83%, respectively. These values were 71%, 90%, 89%, 74% and 80% when the prostate was evaluated combining MR and MRS. The addition of MRS to the MR imaging provides a higher specificity in tumour detection and can be recommended as a problem-solving modality for patients with elevated PSA levels and suspicious TRUS before biopsy.     

磁共振成像在宫颈癌疗效评价中的应用

磁共振成像（MRI）形成三维立体定位解剖成像。通过MRI对比肿瘤体积及信号强度变化,MRI在宫颈癌疗效评估方面有重要价值。随着影像学的发展,磁共振扩散加权成像（DWI）、磁共振波谱（MRS）能提供细胞水平的定性和定量信息,反应肿瘤细胞在治疗中的变化。MRI技术能早期预测局部晚期官颈癌新辅助化疗疗效,为患者个体化治疗提供重要依据。