Dynamic contrast enhanced MRI in prostate cancer

Angiogenesis is an integral part of benign prostatic hyperplasia (BPH), is associated with prostatic intraepithelial neoplasia (PIN) and is key to the growth and for metastasis of prostate cancer. Dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) using small molecular weight gadolinium chelates enables non-invasive imaging characterization of tissue vascularity. Depending on the technique used, data reflecting tissue perfusion, microvessel permeability surface area product, and extracellular leakage space can be obtained. Two dynamic MRI techniques (T2*-weighted or susceptibility based and T1-weighted or relaxivity enhanced methods) for prostate gland evaluations are discussed in this review with reference to biological basis of observations, data acquisition and analysis methods, technical limitations and validation. Established clinical roles of T1-weighted imaging evaluations will be discussed including lesion detection and localisation, for tumour staging and for the detection of suspected tumour recurrence. Limitations include inadequate lesion characterisation particularly differentiating prostatitis from cancer, and in distinguishing between BPH and central gland tumours.     

乳腺癌新辅助化疗前后DCE-MRI血流动力学与病理学对照

目的:探讨乳腺癌新辅助化疗前后动态增强MRI血流动力学变化特点,对新辅助化疗的疗效和预后的评价提供更多依据.方法:新辅助化疗的乳腺癌患者26例,新辅助化疗前后进行乳腺动态增强MRI检查.比较时间-信号强度曲线(TIC)及血流半定量参数在化疗前后变化;化疗后残留病灶的TIC类型与病理学评级进行对照研究.结果:新辅助化疗患...     

Dynamic enhanced MRI predicts chemosensitivity in breast cancer patients

BACKGROUND: Primary chemotherapy for breast cancer is effective as postoperative adjuvant therapy. However, one of the critical disadvantages was a treatment delay for patients with progressive disease. The present study attempts to clarify quantitative parameters on MRI which can be used to predict the sensitivity to treatment in breast cancer patients. METHODS: The subjects consisted of 26 patients with invasive ductal breast cancer who received primary chemotherapy before surgery. The mean maximum tumor dimension was 3.3cm, and 21 cases had nodal involvements. Three cases demonstrated histological grade 3. Dynamic enhanced MRI was evaluated at three different time periods; prior to, in the midst of preoperative chemotherapy, and just before the initial operation. The signal intensity ratio (SIR) and early contrast uptake (ECU) were calculated, as well as the correlation between these dynamic data and the tumor reduction rates were analyzed retrospectively. P-values of less than 0.05 were considered to indicate statistically significant. RESULTS: Responders to chemotherapy had the significantly higher SIR and ECU values than non-responders (p=0.0454 and 0.0334, respectively). ECU value significantly decreased as tumor reduction by chemotherapy (p=0.0028). Pathological tumor dimension was significantly correlated with the tumor size estimated on presurgical MRI (p<0.0001). CONCLUSIONS: Our current series demonstrated the significant correlation between pretreatment MRI data and tumor reduction by chemotherapy in breast cancer patients. With these results, it seems possible to define good and non-responders prior to treatment.     

MRI appearances of the axilla in treated breast cancer.

Differentiation between recurrent axillary disease and changes due to radiotherapy or surgery has major implications for management in patients following breast cancer treatment, but clinical examination of the axilla may be difficult. This study was undertaken to correlate the MRI appearances of the axilla following breast cancer treatment with clinical outcome. 74 women with treated breast cancer were evaluated by MRI (0.5 T) and the appearances defined by consensus. Outcome was assessed by long-term clinical follow-up. 62 women had symptoms related to the axilla while 12 were scanned to stage the axilla. None of the axillary staging group had abnormal MRI appearances and none of these subsequently developed recurrence. The 62 symptomatic women were subdivided according to MRI appearances. 22 had normal axillary appearances, 18 had an axillary mass and 22 women had abnormal axillary appearances (rated mild, moderate and severe) in the absence of a mass. Normal axillary appearances on MRI excluded recurrent disease as the cause of symptoms with a specificity of 94.7% and a positive predictive value (PPV) of 95.5%. The presence of an axillary mass was commonly but not exclusively due to recurrent disease (sensitivity 68.4%, specificity 88.4%, PPV 72.2%). Sensitivity for diagnosis of axillary recurrence was increased to 89.5% with a specificity of 76.7% if the criteria for recurrent disease were taken as either the presence of an axillary mass or severe axillary changes in the absence of a mass lesion.     

Dynamic contrast enhanced perfusion MRI in mycosis fungoides

Mycosis fungoides is a malignant, cutaneous lymphoma of T-helper (TH or CD4+) cells. At presentation, the disease is usually limited to the skin, with lesions that resemble eczema or psoriasis. Neurologic involvement is uncommon. This case demonstrates the conventional MRI and dynamic contrast enhanced perfusion MRI findings in intracerebral mycosis fungoides. T1-weighted spin echo imaging demonstrated a lesion with slightly decreased signal within the body of the corpus callosum. The lesion was isointense with grey matter on axial T2-weighted imaging. Following administration of contrast, there was patchy heterogeneous enhancement. Multiple relative cerebral blood volume (rCBV) measurements were made and the minimum rCBV was 0.30 with the maximum rCBV being 1.61. The mean rCBV was 0.81 +/- 0.49 (average of 10 measurements and standard deviation).     

Follow-up of women with breast cancer: comparison between MRI and FDG PET

The aim of this study was to compare MRI of the breast with ¹⁸F-fluoro-deoxy-glucose (FDG) positron emission tomography (PET) in patients with suspected local or regional breast cancer recurrence or suspected contralateral breast cancer. Thirty-two patients (mean age 57.2 years, age range 32–76 years) with suspected loco-regional recurrence (n=19), chest wall recurrence (n=5), and suspected secondary tumor of the contralateral breast (n=8) underwent MRI of the breast and FDG PET of the whole body and breast region. Cytology/histology (n=17) or a clinical follow-up examination (n=15) with additional imaging served as the standard of reference. A McNemar test was performed to compare PET and MRI, and kappa was determined to quantify agreement of both methods. Sensitivity was 79 and 100%, specificity was 94 and 72%, and accuracy was 88 and 84% for MRI and PET, respectively. Additional metastases outside the field of view of MRI were found in PET in 5 patients. In this study both imaging methods had comparable accuracy. The detection of distant metastases with whole-body PET imaging can influence patient management.     

Drainage across midline to sentinel nodes in the contralateral axilla in breast cancer

The authors report a case of recurrent breast carcinoma in the right chest in a patient who earlier had a right breast mastectomy. Injection of Tc-99m sulfur colloid into the lesion site in the right midchest revealed drainage to a very faint node in the contralateral axilla on the left, an unexpected site, and none to the ipsilateral axilla, the expected site. Disease was found in the left axilla in the sentinel nodes. Lymphoscintigraphy added valuable information in the management of this patient.     

动态增强MR与PSA在前列腺癌诊断及鉴别诊断中的应用价值

目的：探讨MRI快速序列动态增强在前列腺癌(PC)诊断及鉴别诊断中的价值，并观察PSA在PC与前列腺增生(BPH)诊断中的作用。方法：对5例无泌尿系症状健康志愿者、经病理证实的13例前列腺癌和36例前列腺增生患者进行MR平扫、动态增强及延迟扫描，测量并计算病灶和正常组织的相对信号强度值，并绘制正常周围带(PZ)、PC与BPH三者的时间信号强度曲线。结果：PZ轻度强化，并缓慢上升至晚期达峰值；36例BPH早期明显强化并逐渐上升至中晚期达峰值后缓慢下降：13例PC9例早期明显强化，并快速下降，4例T2WI像上弥漫性病灶呈现中晚期强化。PC尤其是晚期患者的PSA值明显高于增生。结论：PZ、PC及BPH的动态强化方式明显不同，结合PSA可对PC的诊断与鉴别诊断起积极作用。     

Detection of primary breast cancer in women with known adenocarcinoma metastatic to the axilla: Use of MRI after negative clinical and mammographic examination

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.     

乳腺癌癌周间质的动态增强MRI及扩散加权成像

目的：研究磁共振动态增强及扩散加权成像上乳腺癌癌周间质的影像学表现,并探讨其对确定乳腺癌肿瘤边界的价值。方法：搜集2012年10月-2014年3月行乳腺 MRI 检查,手术或穿刺活检病理证实为乳腺癌的患者共31例（所选病例均为单侧单中心发病）。测量乳腺癌病灶与病灶周围组织不同方向上的表观扩散系数（ADC）值及信号增强率（SER）,并进行统计学分析。结果：横轴面 DWI 图像：乳腺癌病灶内的 ADC 值显著低于病灶周围组织;乳腺癌周围组织同一层面不同方向的 ADC 值之间差异无统计学意义（P ＞0．05）;但对于同一方向上的不同层面,靠近病灶的第1层（范围约5mm）的 ADC 值小于远离它的3个层面（P ＜0．05）;乳腺癌、癌旁组织、正常侧乳腺组织的平均 ADC 值之间差异具有统计学意义（F ＝32．496,P ＝0．000）。横轴面动态增强图像：乳腺癌病灶内的 SER 显著高于病灶周围组织;但病灶周围组织各层面之间 SER 的差别无统计学意义（P ＞0．05）;病灶周围组织同一层面的不同方向的 SER 之间差异无统计学意义（P ＞0．05）。结论：MR 动态增强的 SER 及 DWI 成像的 ADC 值对乳腺癌与癌周间质组织的判别有一定的敏感性和特异性,有望成为确定乳腺癌范围及手术切缘的有效影像学方法。     

Dynamic contrast enhanced MRI in the differential diagnosis of soft tissue tumors

PURPOSE: The value of the dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI) in differentiating benign and malignant soft tissue tumors was investigated. MATERIALS AND METHODS: Turbo FLASH DCE-MRI was performed on 22 subjects (2-74 years) with soft tissue tumors. Enhancement in the first min (E(max/1)), second min (E(max/2)) and maximum peak enhancement (E(max)), and steepest slope were calculated. Discriminant analyses were performed to reveal parametric differences of benign and malignant lesions. RESULTS: Diagnosis of benign (N = 10) tumors were hemangioma (n = 3), neurogenic tumor (n = 3) lipoma (n = 2), giant cell tumor (n = 1) and desmoid (n = 1), whereas malignant lesions (N = 12) were classified as liposarcoma (n = 5), malignant fibrous histiocytoma (n = 5) and synovial sarcoma (n = 2). For malignant lesions E(max/1) was 65-198%, E(max/2) was 65-145%, E(max) was 78-198%, and steepest slope was 1.45-4.06. For benign lesions these values were 4-98%, 5-105%, 7-125% and 0.67-2.57, respectively. To determine the relation between the variables analysed, Pearson correlation coefficients were calculated. E(max) was found to be highly correlated with other variables (rxy > 0.86, P < 0.0001). Consequently, this variable was excluded from the discriminant analysis. In order to determine discrimination of malignant and benign tumors using E(max/1), E(max/2,) and steepest slope of the enhancement curve logistic regression was applied to the above mentioned data. When combined these parameters had a 95.5% of overall accuracy in classifying benign and malignant lesions (P = 0.004). CONCLUSION: DCE-MRI parameters that thought to be the surrogate markers of tumoral microcirculation and tissue perfusion provides a specific preoperative diagnosis. Dynamic imaging parameters are therefore advocated for monitoring the effect of chemotherapy in soft tissue tumors.     

Impact of PET/CT in comparison with same day contrast enhanced CT in breast cancer management

PURPOSE: To evaluate the impact of F-18 fluorodeoxyglucose (FDG) positron emission tomography with fused computerized tomography (PET/CT) in comparison with same day contrast enhanced CT (CE-CT) in breast cancer management. METHOD: Seventy studies in 49 breast cancer patients, 17 for initial and 53 for restaging disease were included. All patients underwent PET/CT for diagnostic purposes followed by CE-CT scans of selected body regions. PET/CT was started approximately 90 minutes following IV injection of 10-15 mCi of F-18 FDG on a GE Discovery PET/CT system. Oral contrast was given before F-18 FDG injection. The CE-CT was performed according to departmental protocol. RESULTS: Out of a total of 257 lesions, 210 were concordant between PET/CT and CE-CT. There were 47 discordant lesions, which were verified by either biopsy (35) or follow-up (12 PET positive CE-CT negative lesions). PET/CT correctly identified 25 true positive (TP). CE-CT identified 2 TP lesions missed by PET/CT which were false negatives (FNs): one liver metastasis with necrosis, which was nonavid to FDG uptake because of necrosis and a second one missed on abdominal metastatic node, which did not change staging or treatment. PET/CT incorrectly identified 2 false positive lesions while CE-CT incorrectly identified 18 false positive. TP recurrence of the disease was found by PET/CT in 44% (15/34 pts), whereas 56% (19/34 pts) were free of disease. The CE-CT described progression of the disease in 1 true negative PET/CT study and no progression in 2 TP PET/CT studies. The sensitivity, specificity, accuracy, positive productive value, and negative productive value for PET/CT were 97.8%, 93.5%, 97.3%, 99.1%, 85% and for CE-CT were 87.6%, 42%, 82.1%, 91.6%, 31.7%. CONCLUSION: In this study, PET/CT played a more important role than CE-CT scans alone and provided an impact on the management of breast cancer patients.     

3．OT MRI定量动态对比增强对乳腺疾病的应用价值研究

目的 研究3.0T MRI动态对比增强定量参数对乳腺疾病的诊断价值.方法 采用3.0T MRI扫描仪和16通道乳腺相控阵线圈对45例怀疑乳腺肿瘤患者进行动态对比增强MRI检查,共发现病灶52个,其中5例为2个病灶（1例为双侧,4例为单侧）,1例为3个病灶（双侧）,所有2个以上病灶都取最大的病灶纳入研究.分别测量定量血流动力学参数,包括容量转移常数（volume transfer constant,Kttrans）和血管外细胞外间隙容积比（extravascular extracellular space distribute volume per unit tissue volume,Ve）.采用单因素方差分析比较乳腺癌、纤维瘤和其他良性病变的组间差异,受试者特性曲线（receiver operating characteristic curve,ROC）分析良、恶性病变的组间差异.结果 乳腺癌（n=23）的Ktrans和Ve均值分别为（10.18±2.65） min-1和7.64±1.20;良性病变（n=22）的Ktrans和Ve均值分别为（5.68±1.15）nind和8.44±2.01;良性病变中纤维瘤（n=12）的上述均值分别为（7.31±1.42） min1和11.25±2.75,其他良性病变（n=10）的上述均值分别为（3.73±0.83） min1和5.07±1.13.乳腺癌与良性病变间Ktrans的差异有统计学意义（F值为4.271,P值＜0.05）,Ve的差异无统计学意义（F值为1.553,P值＞0.05）;乳腺癌、乳腺纤维瘤与其他良性病变3组间Ktrans和Ve的差异均有统计学意义（F值分别为4.316和3.944,P值均＜0.05）.以最大约登指数为最佳诊断切点值,Ktrans和Ve判断乳腺良恶性病变的敏感度分别为87.5％和8l.3％;特异度分别为55.6％和38.9％.综合2个定量参数作为联合指标诊断良、恶性病变的敏感度、特异度和准确度分别为91..％（21/23）,77.3％ （17/22）和84.4％（38/45）.结论 3.0T MRI动态对比增强定量血流动力学参数Ktrans对乳腺良恶性病变的鉴别诊断具有很高的诊断价值,Ve对鉴别乳腺癌与纤维瘤具有一定的诊断价值.     

Ex vivo MRI of axillary lymph nodes in breast cancer

Purpose

To provide a strategy for precise co-localization of lymph nodes on axillary lymph-node dissection (ALND) specimens both on pathology and MR.To identify nodal features suggestive of metastatic involvement on a node-to-node basis.

Materials and methods

National Institutional review-board approved this prospective study of 18 patients with breast cancer referred for ALND. Ex vivo T1 and inversion recovery (IR) T2 WI of ALND specimens tightly positioned within scaled plastic cranes was performed immediately after surgery. The correspondence of MR-based or pathologically based nodes location was assessed. The MR size and morphological presentation of metastatic and normal nodes were compared (Student's t-test or Mann–Whitney test). Quantitative variables were compared using Pearson coefficient.

Results

207 nodes were retrieved on pathology and 165 on MR. MR–pathological correlation of nodes location was high regarding MR-identified nodes (r = 0.755). An MR short axis threshold of 4 mm yielded the best predictive value for metastatic nodal involvement (Se = 78.6%; Sp = 62.3%). Irregular contours (Se = 35.7%; Sp = 96.7%), central nodal hyper-intensity on IR T2 WI (Se = 57.1%; Sp = 91.4%), and a cortical thickness above 3 mm (Se = 63.6%; Sp = 83.2%) were significantly associated with metastatic involvement.

Conclusion

Ex vivo MR allows node-to-node correlation with pathology. Morphological MR criteria can suggest metastatic involvement.     

原发性胸椎原始神经外胚层肿瘤的动态增强MRI表现

目的 初步探讨原始神经外胚层肿瘤(PNET)的动态增强MRI表现，以及对其诊断及鉴别诊断的价值。方法 用动态增强MRI方法对已手术和病理证实的2例胸椎PNET行3次MR检查并进行前瞻性研究。结果 在信号强度-时间和对比增强率．时间曲线上，2例PNET3次检查均表现为快升慢降型，即肿瘤早期就开始迅速增强，上升峰极陡，60～120s即达到高峰水平，然后保持平坦，3．5min内未见明显下降曲线。结论 动态增强MRI扫描能帮助对PNET进行早期诊断和鉴别诊断，从而为临床选择治疗方案及估计预后提供较为可靠的依据。