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The development of targeted therapies is a major breakthrough in the treatment of cancer. By evoking necrosis and cavitation, evaluation based on tumour size alone, as is done in the RECIST criteria, is no longer an adequate method. New molecular and functional imaging techniques are developed. This review focuses on the use of new imaging modalities for the evaluation of treatment response of pathway based targeted therapies. First, the basic principles of functional and molecular imaging modalities are briefly discussed. Thereafter, their clinical application in targeted therapies is correlated to the underlying biological mechanism. In this way, the best method for response evaluation for a new agent can be identified.

Background: In patients with prostate cancer who are deemed to be at intermediate or high risk of having nodal metastases, invasive diagnostic pelvic lymph-node dissection (PLND) is the gold standard for the detection of nodal disease. However, a new lymph-node-specific MR-contrast agent ferumoxtran-10 can detect metastases in normal-sized nodes (ie, <8 mm in size) by use of MR lymphoangiography (MRL). In this prospective, multicentre cohort study, we aimed to compare the diagnostic accuracy of MRL with up-to-date multidetector CT (MDCT), and test the hypothesis that a negative MRL finding obviates the need for a PLND., Methods: We included consecutive patients with prostate cancer who had an intermediate or high risk (risk of >5% according to routinely used nomograms) of having lymph-node metastases. All patients were assessed by MDCT and MRL, and underwent PLND or fine-needle aspiration biopsy. Imaging results were correlated with histopathology. The primary outcomes were sensitivity, specificity, accuracy, NPV, and PPV of MRL and MDCT. This study is registered with ClinicalTrials.gov, number NCT00185029., Findings: The study was done in 11 hospitals in the Netherlands between April 8, 2003, and April 19, 2005. 375 consecutive patients were included. 61 of 375 (16%) patients had lymph-node metastases. Sensitivity was 34% (21 of 61; 95% CI 23-48) for MDCT and 82% (50 of 61; 70-90) for MRL (McNemar's test p<0.05). Specificity was 97% (303 of 314; 94-98) for MDCT and 93% (291 of 314; 89-95) for MRL. Positive predictive value (PPV) was 66% (21 of 32; 47-81) for MDCT and 69% (50 of 73; 56-79) for MRL. Negative predictive value (NPV) was 88% (303 of 343; 84-91) for MDCT and 96% (291 of 302; 93-98) for MRL (McNemar's test p<0.05). Of the 61 patients with lymph-node metastases, 50 were detected by MRL, of which 40 (80%) had metastases in normal-sized lymph nodes. The high sensitivity and NPV of MRL imply that in patients with a negative MRL, the chance of positive lymph nodes is less than 11/302 (4%)., Interpretation: MRL had significantly higher sensitivity and NPV than MDCT for patients with prostate cancer who had intermediate or high risk of having lymph-node metastases. In such patients, after a negative MRL, the post-test probability of having lymph-node metastases is low enough to omit a PLND.

The value of pharmacokinetic parameters derived from fast dynamic imaging during initial enhancement in characterizing breast lesions on magnetic resonance imaging (MRI) was evaluated. Sixty-eight malignant and 34 benign lesions were included. In the scanning protocol, high temporal resolution imaging was combined with high spatial resolution imaging. The high temporal resolution images were recorded every 4.1 s during initial enhancement (fast dynamic analysis). The high spatial resolution images were recorded at a temporal resolution of 86 s (slow dynamic analysis). In the fast dynamic evaluation pharmacokinetic parameters (K(trans), V(e) and k(ep)) were evaluated. In the slow dynamic analysis, each lesion was scored according to the BI-RADS classification. Two readers evaluated all data prospectively. ROC and multivariate analysis were performed. The slow dynamic analysis resulted in an AUC of 0.85 and 0.83, respectively. The fast dynamic analysis resulted in an AUC of 0.83 in both readers. The combination of both the slow and fast dynamic analyses resulted in a significant improvement of diagnostic performance with an AUC of 0.93 and 0.90 (P = 0.02). The increased diagnostic performance found when combining both methods demonstrates the additional value of our method in further improving the diagnostic performance of breast MRI.

Aim: To compare the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in the diagnosis of lymph node metastases in prostate cancer., Methods: After a comprehensive literature search, studies were included that allowed construction of contingency tables for detection of lymph node metastases using CT or MRI. In addition, a summary receiver-operating characteristic (ROC) analysis was performed., Results: A total of 24 studies were included. For CT, pooled sensitivity was 0.42 (0.26-0.56 95% CI) and pooled specificity was 0.82 (0.8-0.83 95% CI). For MRI, the pooled sensitivity was 0.39 (0.22-0.56 95% CI) and pooled specificity was 0.82 (0.79-0.83 95% CI). The differences in performance of CT and MRI were not statistically significant., Conclusion: CT and MRI demonstrate an equally poor performance in the detection of lymph node metastases from prostate cancer. Reliance on either CT or MRI will misrepresent the patient's true status regarding nodal metastases, and thus misdirect the therapeutic strategies offered to the patient.

Aims: Invasive lobular carcinoma of the breast (ILC) is known to be substantially underestimated by mammography, which makes correct planning of treatment difficult. MRI has been proposed as a valuable adjunct to mammography. The purpose of the current study is to evaluate its value, compare it to mammography and assess the possible causes of over- and underestimation of lesion size on MRI., Method: The mammograms and MRI scans of 67 consecutive patients with ILC were retrieved and re-evaluated. Size measurements were correlated to the sizes extracted from the pathology report., Results: MRI measurements correlated better to pathologic size (r=0.85) than mammographic measurements (r=0.27). Underestimation of tumour size was more common on mammography (p<0.001); overestimation occurred with equal frequency (p=0.69). Overestimation on MRI, caused by non-malignant findings, was attributed to enhancing lobular carcinoma in situ., Conclusion: MRI is a more accurate modality for determining tumour size in patients with ILC than mammography. The typical underestimation of lesion size by mammography can be prevented with the aid of MRI, without increasing the risk of lesion overestimation.

Systemic chemotherapy is effective in only a subset of patients with metastasized colorectal cancer. Therefore, early selection of patients who are most likely to benefit from chemotherapy is desirable. Response to treatment may be determined by the delivery of the drug to the tumor, retention of the drug in the tumor and by the amount of intracellular uptake, metabolic activation and catabolism, as well as other factors. The first aim of this study was to investigate the predictive value of DCE-MRI with the contrast agent Gd-DTPA for tumor response to first-line chemotherapy in patients with liver metastases of colorectal cancer. The second aim was to investigate the predictive value of 5-fluorouracil (FU) uptake, retention and catabolism as measured by localized (19)F MRS for tumor response to FU therapy. Since FU uptake, retention and metabolism may depend on tumor vascularization, the relationship between (19)F MRS and the DCE-MRI parameters k(ep), K(trans) and v(e) was also examined (1). In this study, 37 patients were included. The kinetic parameters of DCE-MRI, k(ep), K(trans) and v(e), before start of treatment did not predict tumor response after 2 months, suggesting that the delivery of chemotherapy by tumor vasculature is not a major factor determining response in first-line treatment. No evident correlations between (19)F MRS parameters and tumor response were found. This suggests that in liver metastases that are not selected on the basis of their tumor diameter, FU uptake and catabolism are not limiting factors for response. The transfer constant K(trans), as measured by DCE-MRI before start of treatment, was negatively correlated with FU half-life in the liver metastases, which suggests that, in metastases with a larger tumor blood flow or permeability surface area product, FU is rapidly washed out from the tumor., (c 2006 John Wiley & Sons, Ltd.)

Imaging plays a vital role in the management of patients with cancer. Not only is it important for diagnosis, indicating sites of abnormality, and guiding biopsies, but it is also crucial in assessing disease extent and thereby determining treatment. In this review, conventional imaging techniques such as ultrasound, computed tomography, magnetic resonance imaging, and [18F]fluorodeoxyglucose-positron emission tomography are described, with attention to their mechanisms of action, and their strengths and weaknesses in diagnosis and staging of tumors. New developments are addressed and radiation safety issues are highlighted. In addition, we describe current and expected future uses of imaging techniques in oncology. Given that each technique has its inherent strengths and weaknesses, the combination of the methods will result in improved diagnosis, staging, and treatment prediction and monitoring.

Rationale and Objectives: The purpose of the study was a preliminary evaluation of a new oral, manganese-based, liver-specific contrast medium (CMC-001; CMC Contrast AB, Malmoe, Sweden) for magnetic resonance imaging (MRI) in patients with liver metastases., Materials and Methods: The study included 10 consecutive patients with known liver metastases. Patients underwent abdominal MRI as a supplement to routine diagnostics. Patients fasted for at least 10 hours before ingesting CMC-001 (1.6 g manganese chloride tetrahydrate, 1 g alanine, and 1,600 IU vitamin D3 were dissolved in water). MRI took place before and 2 hours after drinking CMC-001. The 1.5-T MRI protocol included two-dimensional T1w sequences to visualize metastases. T2w and diffusion weighted imaging (DWI) sequences were used to identify cysts and blood vessels correspondingly., Results: The intake of CMC-001 caused an increase in the signal intensity of the "healthy" liver tissue, making the internal structure of the liver significantly better visualized. Compared with our routine examinations, MRI showed more metastases in four patients and allowed determining a more precise outline of metastases., Conclusion: CMC-001 improves imaging of liver metastases in comparison with computed tomography and with MRI without CMC-001.

Objectives: To determine whether the failure of chemotherapy in patients with regionally metastatic or unresectable transitional cell carcinoma (TCC) of the bladder can be predicted early in the course of chemotherapy with magnetic resonance (MR) imaging., Methods: In this prospective study, 36 patients with regionally metastatic or unresectable TCC of the urinary bladder underwent MR imaging before and after two, four, and six cycles of chemotherapy with Methotrexate, Vinblastine, Adriamycin (doxorubicin) and Cisplatin (MVAC). The response after two cycles of MVAC was evaluated by using conventional tumour size parameters with unenhanced MR imaging and with changes in the time to the start of tumour or lymph node enhanced at fast dynamic contrast-enhanced MR imaging. The results obtained with these techniques were compared with the findings at histopathology in cystectomy or transurethral resection specimens that were obtained after chemotherapy. Duration of survival was defined as the time from the start of chemotherapy until disease-specific death. Kaplan-Meier curves were drawn to determine the difference in prognosis between responders and nonresponders., Results: After two cycles of chemotherapy, the accuracy, sensitivity, and specificity in distinguishing responders from nonresponders with conventional MR imaging were 69%, 81%, and 50%, respectively. With the fast dynamic contrast-enhanced technique, accuracy, sensitivity, and specificity were 92%, 91%, and 93% respectively. The median bladder cancer specific survival was 28 months for all patients studied. Responders to chemotherapy at fast dynamic contrast-enhanced MR had better median disease-specific survival than nonresponders (42 months vs. 12 months [p<0.0001])., Conclusion: We can predict whether a patient will respond to chemotherapy after two cycles of chemotherapy with fast dynamic contrast-enhanced MR imaging.

The aim of the study was to evaluate mammography in detecting and staging of invasive lobular carcinoma (ILC) in order to assess the performance and impact of observer variability. Forty-two cases of ILC were retrospectively evaluated twice by two breast radiologists. Mammographic performance as well as intra- and interobserver variations was evaluated. Thirty-five percent to 37% of the cases were understaged. The largest differences between radiologists were found in the breast imaging reporting and data system (BIRADS) classification and staging performance. These results can have serious influence on patient management.

We have previously shown that the dense vascular network in mouse brain allows for growth of human melanoma xenografts (Mel57) by co-option of preexisting vessels. Overexpression of recombinant vascular endothelial growth factor-A (VEGF-A) by such xenografts induced functional and morphologic alterations of preexisting vessels. We now describe the effects of VEGF-A expression on visualization of these brain tumors in mice by magnetic resonance imaging (MRI), using gadolinium diethylenetriaminepenta-acetic acid (Gd-DTPA) and ultra small paramagnetic iron oxide particles (USPIO) as contrast agents. Brain lesions derived from (mock-transfected) Mel57 cells were undetectable in MRI after Gd-DTPA injection. However, the majority of such lesions became visible after injection of USPIO, due to the lower vascular density in the lesions as compared to the surrounding parenchyma. In contrast, VEGF-A-expressing lesions were visualized using Gd-DTPA-enhanced MRI by a rapid circumferential enhancement, due to leaky peritumoral vasculature. USPIO-enhanced MRI of these tumors corroborated the immunohistochemic finding that peritumorally located, highly irregular and dilated vessels were present, while intratumoral vessel density was low. Our study shows that VEGF-A is a key factor in imaging of brain neoplasms. Our data also demonstrate that, at least in brain, blood-pool agent-enhanced MRI may be a valuable diagnostic tool to detect malignancies that are not visible on Gd-DTPA-enhanced MRI. Furthermore, the involvement of VEGF-A in MRI visibility suggests that care must be taken with MRI-based evaluation of antiangiogenic therapy, as anti-VEGF treatment might revert a tumor to a co-opting phenotype, resulting in loss of contrast enhancement in MRI., (Copyright 2003 Wiley-Liss, Inc.)

Objective: To investigate if a simple axial spin echo (SE) image can be used for reliable assessment of pulmonary artery dimensions in patients with Marfan syndrome., Methods: Fifty Marfan patients (mean age 33 +/- 10 years; 34 men, 16 women) and 15 normal subjects (mean age 28 +/- 4 years; nine men, six women) underwent cardiac magnetic resonance imaging (MRI). Pulmonary artery dimensions were obtained on axial SE images at two different levels: (1) the level of the pulmonary artery root, and (2) the level of the pulmonary artery bifurcation. To evaluate the accuracy of axial plane measurements 10 Marfan patients also underwent contrast-enhanced MR angiography (CE-MRA)., Results: In the 10 Marfan patients who also underwent CE-MRA, the mean diameter at the pulmonary bifurcation assessed with CE-MRA (31.5 +/- 3.6 mm) was almost equal to mean diameter assessed with axial SE (30.7 +/- 3.6 mm). Agreement of methodology according to Bland and Altman analysis showed a 95% confidence interval ranging from -2.6 to + 4.4 mm for all distances of the pulmonary artery root. In Marfan patients the mean right-left diameter measured on both axial SE images and CE-MRA was approximately 2.5 mm larger than the anterior-right and anterior-left diameters (p < 0.001)., Conclusions: Axial SE MRI is a reliable and easy acquisition to measure pulmonary artery dimensions in patients with Marfan syndrome, and could be used for follow-up, especially in patients with severe involvement of the cardiovascular system. Not only the pulmonary artery trunk but also the asymmetric pulmonary root should be measured, although the clinical relevance of the asymmetric root is not yet known.

The aim of this study was to determine which morphological features of low-intensity lesions in the peripheral zone of the prostate are predictable of prostate cancer on pre-biopsy T2-weighted integrated endorectal phased-array MR images. The MR examinations were performed in 69 consecutive patients with elevated level of prostate-specific antigen (>4 ng/ml) and/or a positive digital rectal examination before transperineal 12-site biopsy. Two radiologists evaluated presence of lesions, their morphological features, and possibility of malignancy in divided into four sections of the peripheral zone. Imaging analysis findings were compared with biopsy results. Discriminative features were selected by stepwise logistic regression. Descriptive statistics and receiver operating characteristics (ROC) curves were also calculated. Sixty-eight benign lesions and 23 malignant lesions were found. Wedge shape and diffuse extensions without mass effect were significantly associated with benignity ( P=0.0105 and 0.002, respectively). Lesion size was significantly associated with malignancy ( P=0.0001). For evaluating probability of malignancy for lesions, regression model showed a comparable accuracy with the total impression for the readers in ROC analysis (Az 0.9095 vs 0.9266, respectively). Wedge shape, diffuse extension without mass effect, and size are the morphological features of low-intensity lesions in the peripheral zone on pre-biopsy T2-weighted MR images that give the best prediction of malignancy.

Background: Although breast cancer screening is recommended to start at a younger age for women with a hereditary risk of breast cancer, the sensitivity of mammography for these women is reduced. We compared magnetic resonance imaging (MRI) with mammography to determine which is more sensitive and whether MRI could play a role in the early detection of breast cancer for these women., Methods: We constructed a retrospective cohort of all breast MRI and mammography surveillance reports made in our department from November 1994 to February 2001. All of the 179 women in the cohort had received biannual palpation in addition to annual imaging by MRI, mammography, or both. The 258 MRI images and the 262 mammograms were classified with the use of the BI-RADS (i.e., Breast Imaging Reporting and Data System) scoring system, which has five categories to indicate the level of suspicion of a lesion. Receiver operator characteristic curves were generated for MRI and mammography, and the area under each curve (AUC) was assessed for the entire cohort of 179 women and for a subset of 75 women who had received both an MRI and a mammographic examination within a 4-month period. All statistical tests were two-sided., Results: In the cohort of 179 women, we detected 13 breast cancers. Seven cancers were not revealed by mammography, but all were detected by MRI. For the entire cohort, the AUC for mammography was 0.74 (95% confidence interval [CI] = 0.68 to 0.79), and the AUC for MRI was 0.99 (95% CI = 0.98 to 1.0). For the subset of women who had both examinations, the AUC for mammography was 0.70 (95% CI = 0.60 to 0.80), and the AUC for MRI was 0.98 (95% CI = 0.95 to 1.0)., Conclusion: MRI was more accurate than mammography in annual breast cancer surveillance of women with a hereditary risk of breast cancer. Larger prospective studies to examine the role of MRI in screening programs are justified.

Purpose: To determine the appropriate use of magnetic resonance (MR) imaging for preoperative staging of prostate cancer., Materials and Methods: Literature review was performed by using the principles of evidence-based medicine and medical technology assessment. A decision analytic model was used to compare (a) the strategy that radical prostatectomy is performed on the basis of clinical staging with (b) the strategy that extracapsular disease detected at MR imaging contraindicates radical prostatectomy in patients who were considered surgical candidates on the basis of clinical staging., Results: After review of the literature, expert panel opinion did not recommend MR staging. No studies in which therapeutic efficacy was addressed were found. The decision analytic model indicated that the strategy including MR staging decreased costs (MR imaging, $10,568; radical prostatectomy, $11,669) and resulted in almost equal life expectancy (MR imaging, 12.59 years; radical prostatectomy, 12.60 years) and quality-adjusted life-years ([QALYs] MR imaging, 12.53; radical prostatectomy, 12.52). Results of sensitivity analyses demonstrated that the MR strategy was both more effective and less costly if the prior probability of extracapsular disease was at least 39% when considering QALY and 50% when considering unadjusted life expectancy., Conclusion: It is not yet conclusively determined whether preoperative MR staging is appropriate, but results of decision analysis suggest that MR staging is cost-effective for men with moderate or high prior probability of extracapsular disease.

Objective: The purpose of this study was to evaluate the accuracy of breath-hold contrast-enhanced MR angiography in the assessment of renal artery stenosis and accessory renal arteries using a standard dose of gadolinium., Subjects and Methods: Thirty-eight patients suspected of having renal artery stenosis underwent MR angiography and intraarterial digital subtraction angiography, which was the method of reference. Three-dimensional gradient-echo MR subtraction angiography (TR/TE, 5.8/1.8 msec) was performed on a 1.5-T imager using a phased array body coil. Before imaging, a separate timing bolus sequence was used, administering 1.0 ml of contrast agent. Gadopentetate dimeglumine (15 ml) was injected using an MR power injector. Two observers, who were unaware of each other's interpretation and of MR findings, assessed digital subtraction angiography. Likewise, two other observers assessed MR angiography., Results: Digital subtraction angiography depicted 75 main and 17 accessory renal arteries (n = 92). All main renal arteries and 13 accessory renal arteries were identified on MR angiography. Compared with digital subtraction angiography, MR imaging correctly classified 57 of 66 arteries without a hemodynamically significant stenosis (0-49%), 22 of 22 arteries as significantly stenotic (50-99%), and four of four occluded arteries; five stenoses were overestimated. There was one false-positive finding of an accessory renal artery on MR angiography that was identified retrospectively on digital subtraction angiography. Interobserver agreement was high. Sensitivity and specificity for grading significant stenosis were 100% and 85%, respectively., Conclusion: Contrast-enhanced MR angiography, using +/-0.1 mmol/kg of gadolinium, is an accurate method in the assessment of renal artery stenosis and accessory renal arteries.

In this article the role of MR imaging in the management of cervical cancer is reviewed and illustrated. The appearance of the normal uterine cervix and of cervical carcinoma is shown. Important factors for optimal MR imaging of cervical carcinoma are reviewed. The value of MR imaging in the staging of cervical carcinoma is illustrated by showing parametrial invasion and lymph node involvement. Finally, the value of MR imaging staging is compared with clinical staging, CT staging, and surgical findings. The role of new imaging techniques, such as fast dynamic enhanced MR imaging, is described.

The authors investigated the feasibility of a multisection proton magnetic resonance (MR) spectroscopic imaging technique for the acquisition of metabolic information in the human prostate. Multisection MR spectroscopic imaging was performed of a citrate phantom and of the prostates of eight adult volunteers. High-quality proton MR spectra and citrate metabolite maps of the prostate were obtained with this method.

Prostate and urinary bladder cancer are the most frequently encountered malignancies of the urinary tract. Appropriate use of the different imaging techniques is crucial for accurate assessment of prognosis and for the development of appropriate treatment planning. Especially determination of local tumor extension and detection of nodal or bone metastases is extremely important. In this regard MR imaging is the most promising imaging technique. Therefore, in this review its role in staging these malignancies is evaluated and compared with clinical staging, and other imaging techniques. Finally, future developments, such as new sequences, new contrast agents, the role of surface coils and MR-guided biopsy, are considered. Also, the preferred radiological approach is discussed.

Ovarian tumors of borderline malignancy are low-grade malignant neoplasms, and have a rather good prognosis. They account for approximately 10-20% of all ovarian tumors. Very few reports available in literature that analyses ultrasound and MR findings in establishing the diagnosis. The purpose of this study is to describe eight cases of ovarian tumors of borderline malignancy with dynamic gadolinium-enhanced MR imaging. Comparison is made with CA 125 serum levels and ultrasound findings. Early enhancing endocystic vegetations, local cystic masses in, and (irregular) thickened walls of large multicystic tumors were important findings in borderline malignant tumors. The accuracy to detect a malignant tumor of borderline malignancy with CA 125, ultrasound and MRI in these eight cases was 50, 63 and 75%, respectively. MRI is a valuable imaging modality to characterize adnexal tumors and might play a role in preoperative evaluation of borderline malignancies.

The first pass phase of contrast material is most important to study vascularization and perfusion of tissue and can be studied using dynamic magnetic resonance (MR) imaging. The purpose of this prospective study was to evaluate the usefulness of pre-contrast vs. post-contrast and fast dynamic MR imaging in the pre-operative staging of cervical carcinomas. To assess the normal onset of enhancement of the uterus and cervix 15 volunteers underwent dynamic MR imaging. Forty-two consecutive patients with invasive cervical cancer underwent pre-operative evaluation using MR imaging. The results of the MR examinations were correlated with clinical (FIGO) staging under anaesthesia (n = 42) and with histopathological findings after operation (n = 26). The staging results of pre-contrast T1-weighted and T2-weighted turbo spin-echo (TSE) MR images, pre-contrast MR images plus post-contrast enhanced (two dimensional fast low angle shot (FLASH 2-D) post contrast), pre-contrast MR images plus post-contrast enhanced plus fast dynamic enhanced (single slice turbo fast low angle shot (turbo FLASH)) MR images compared to histopathology (n = 26) were 77%, 81% and 85% respectively. The improvement was statistically not significant. The result of MR staging compared to clinical staging (n = 42) with pre-contrast MR images was correct in 79% of the cases. Pre-contrast MR images combined with post-contrast MR images did not significantly improve staging accuracy (83%). Pre-contrast plus post-contrast plus fast dynamic MR imaging improved staging to 91%. However, the improvement was only statistically significant for one reader (P = 0.01), whereas the improvement of the second reader was not significant (P = 0.07). The single slice turbo FLASH images showed enhancement of all squamous cell carcinomas (n = 32) with an average onset of 5s (range 4-8s) during the first 45s of bolus injection of gadolinium. The normal cervix showed enhancement with an average of 10s (range 6-14 s). FLASH 2-D post-contrast images showed less intense enhancement of the cervical tumours with respect to the parametria and other surrounding structures. Fast dynamic MR imaging and to a lesser degree post-contrast MR imaging showed a higher level of confidence than pre-contrast MR. Fast dynamic MRI compared with clinical staging (n = 42) was correct in 91% (38/42) and to histopathology in 85% (22/26). Comparison of clinical staging with histopathology was 85% (22/26). In conclusion, fast dynamic MR imaging is superior to post-contrast and pre-contrast MR imaging and is at least as good as clinical staging in the evaluation of cervical carcinoma.

The treatment and prognosis of urinary bladder cancer are largely determined by the tumour stage and the presence or not of metastases. Magnetic resonance imaging and clinical staging complement each other. Magnetic resonance imaging is the most accurate technique for differentiating the various stages of deep tumour infiltration and for detecting metastases, whereas clinical staging is the best technique for differentiating between post-biopsy effects and the various stages of superficial tumours. The role played by magnetic resonance imaging in the staging of this disease and the monitoring of therapy is reviewed and illustrated. Finally, the authors present an overview of the current and future applications of this technique.

Treatment and prognosis of urinary bladder cancer largely are determined by the tumor stage and presence of metastases. MR imaging and clinical staging complement each other. MR imaging is the most accurate technique for differentiating the various stages of deep tumor infiltration and detection of metastases, whereas clinical staging is the best technique for differentiating between postbiopsy effects and the various stages of superficial tumors. The role of MR imaging in staging of this disease and monitoring of therapy is reviewed and illustrated. Finally, the authors present an overview of current and future applications of this technique.

Background: Recently the potential of magnetic resonance (MR) methods for non-invasive diagnosis and therapy evaluation of prostate cancer has improved substantially. In this study proton MR spectroscopy (1H MRS) was explored for the detection of cancer in the prostate., Patients and Methods: Employing an endorectal probe localized 1H MRS and contrast enhanced MR imaging was performed on the prostate of healthy volunteers and of patients with benign prostatic hyperplasia (BPH) and/or prostate cancer (PCa)., Results: 1H MR spectra of the human prostate showed major signals for citrate, creatine and choline compounds. For cancer tissue the average citrate/choline signal ratio was significantly lower than for BPH and non-cancerous peripheral and central zone tissue, but individual ratios overlapped with ratios for normal central zone and BPH tissue. Low citrate/choline ratios in tumour tissue correspond with early MR contrast enhancement., Conclusions: 1H MRS has potential for non-invasive detection and follow-up of tumours in the prostate.

Migration of thoracic epidural radio-opaque catheters was evaluated in 25 patients scheduled for thoracic surgery in the supine position (n = 5) or in the lateral position with lateral extension of the thoracic spine (n = 20). Chest radiography was performed daily for 3 days after operation. Eighty-nine per cent of catheter tips were visualised in the epidural space. The catheter tip position was unchanged in all patients operated upon in the supine position. In the group operated upon in the lateral position, the catheter tip retracted from day 1 to day 2 by an average of 0.69 cm (SD 1.08; p < 0.05); from day 2 to day 3 the average retraction was 0.35 cm (SD 0.67; p < 0.05).

This report describes the use of an endorectal coil and a double spin-echo pulse sequence for localized 1H MR spectroscopy of the normal prostate in volunteers. The spectra showed well-resolved signals for citrate, (phospho)choline, and creatine protons. Additional signals were assigned to taurine and myoinositol protons. J modulation of the main and outer peaks of citrate could be monitored in vivo. Apparent relaxation times T1 and T2 have been estimated for the methyl protons of cholines and creatine. An effective T1 relaxation time was estimated for the main peaks of the citrate multiplet. Ratios of the integrals of these resonances have been evaluated, and tissue contents of choline and creatine were estimated using the H2O signal as an internal reference. Spectroscopic imaging experiments revealed a lower relative citrate signal in central parts of the prostate than in peripheral parts.

In this study we analyze MR-negative malignant lesions of the breast. A total of 204 patients with palpable and/or mammographic lesions were studied. The MR technique consisted of the turbo FLASH and MP-RAGE subtraction techniques. All patients underwent surgical biopsy and/or mastectomy and all specimens were examined by the correlative radiologic-histologic mapping technique. A total of 208 lesions were evaluated; 145 turned out to be malignant and 63 proved to be benign. Six malignant lesions were misinterpreted as benign on MR imaging; thus, suspicious contrast enhancement was present in 96 % of the lesions detected by mammography, US, or clinical examination. Especially 4 of the 17 ductal carcinoma in situ (DCIS) lesions were misinterpreted (23.5 %). Despite optimal technique, 6 malignant lesions were not identified by MR imaging. The highest prevalence of these MR occult lesions was in the group of DCIS. Although MR imaging has an important role in the evaluation of breast lesions and, primarily, in ruling out malignancy, one should be aware of the fact that false-negative MR findings do occur.

Mild hyperhomocysteinaemia (mHH) is an independent risk factor for premature arteriosclerosis. We investigated the accuracy in the detection of early arteriosclerotic lesions in such patients. The left and right wall of the abdominal aorta, the aortic bifurcation and both common iliac arteries were evaluated with gated T1-weighted magnetic resonance imaging (gT1 MRI) and gated two-dimensional (2D) time-of-flight magnetic resonance angiography (g2D-TOF MRA) and were compared with intra-arterial digital subtraction angiography (iaDSA) in 11 patients with arteriosclerosis and mHH. Six patients showed arteriosclerosis in one or more of the total number of 55 studied arterial segments with iaDSA. Thirty-two of 37 normal and 12 of 18 stenotic segments with gT1 MRI, and 29 normal and 6 stenotic segments with g2D-TOF MRA, were correctly classified. Sensitivity of gT1 MRI and g2D-TOF MRA versus iaDSA was 67 and 33 %, the specificity was 86 and 78 % and the accuracy was 80 and 64 %, respectively. We conclude that arteriosclerosis in patients with mHH is a regular finding, and gT1 MRI in such patients is an acceptable technique.

Objective: The purpose of this study was to evaluate a magnetization-prepared-rapid gradient-echo (MP-RAGE) sequence as a three-dimensional (3D) T1-weighted MR imaging technique to reveal lymph node metastases from carcinoma of the bladder and the prostate., Subjects and Methods: Using a 3D T1-weighted MP-RAGE sequence, MR images of 134 consecutive patients with prostatic carcinoma (n = 63) or urinary bladder carcinoma (n = 71) who were scheduled for radical prostatectomy or radical cystectomy were correlated with histopathologic findings after fine-needle aspiration biopsy (FNAB) (n = 6), open or laparoscopic pelvic lymph node dissection (n = 127), or autopsy (n = 1). MR imaging was used 10 times to guide FNAB in nine patients., Results: The sensitivity, specificity, accuracy, and positive predictive valve of the technique were 75%, 98%, 90%, and 94%, respectively. Thin-slice (1.2-mm) multiplanar reconstructed images correctly revealed diseased nodes in 33 patients. However, MR imaging failed to reveal microscopic metastatic deposits in normally sized nodes in 11 patients. Two other patients had enlarged nodes without metastasis. Furthermore, FNAB guided by MR imaging revealed metastases in six of nine patients., Conclusion: MR imaging with a 3D MP-RAGE sequence was accurate in revealing nodal metastases from carcinoma of the prostate and bladder. This imaging technique can be used to select patients for biopsy or laparoscopic pelvic lymph node dissection.

Objective: To evaluate the accuracy of MR imaging of the prostate with an endorectal surface coil in determining presence, localization, volume, and local stage of prostate carcinoma., Subjects and Methods: MR images of 34 patients with biopsy-proven cancer were correlated retrospectively with the histologic mappings of radical prostatectomy specimens. The volume and number of tumor lesions of MR images were calculated and compared with the surgical specimens used as the gold standard. Tumor stage based on MR imaging was compared with the pathologic stage according to the TNM classification. Predictive values were calculated separately for all lesions and for the lesions correctly localized with MR imaging., Results: MR imaging correctly depicted the location of 67% of the tumors. Twenty percent of the lesions depicted by MR imaging appeared to be false-positive errors. The tumors that were missed were located centrally and ventrally in the prostate. Tumor volume as shown by MR imaging was within a 25% range of the actual tumor volume in 10 cases, overestimated in 16 cases, and underestimated in eight cases. Histopathology showed capsular penetration in 12 of 34 patients (35%) and in 14 of 52 lesions (27%). Sensitivity, specificity, and positive predictive values were 43%, 84%, and 55%, respectively. Histologically, capsular penetration extended less than 1 mm into the periprostatic adipose tissue in seven patients. Sensitivity for capsular penetration less than 1 mm was 14%. Sensitivity for capsular penetration more than 1 mm was 71%. Accuracy for differentiating a pT2 from a pT3 tumor was 68%., Conclusion: Results from this study indicate that the accuracy of the technique was not satisfactory for predicting actual tumor volume. Tumor detection and localization was more accurate in the peripheral zone than in the central zone. Accuracy was poor for detecting capsular penetration of less than 1 mm, but accuracy was much better for penetration of more than 1 mm. Because recent reports suggest that capsular penetration of less than 1 mm does not adversely affect surgical cure, MR imaging still may be practical in the selection of patients for radical prostatectomy.

Since the introduction, pelvic MRI has been considered the best non-invasive technique for primary staging of urinary bladder cancer. Before using MRI an understanding of normal and pathological MR images of the urinary bladder is essential. This review therefore describes the MR anatomy of the urinary bladder as well as the appearances of carcinoma. MRI plays an important clinical role in staging the primary tumour. In superficial tumours, clinical staging, which includes transurethral biopsy, is the best technique. For invasive tumours, MRI is superior to other techniques such as CT scanning, transvesical ultrasonography and clinical staging. A limitation of both MRI and CT scanning is their inability to recognize minimal tumour growth in the muscle layer of the bladder wall, or to differentiate between post-transurethral resection oedema and tumour. Therefore, in all patients with urinary bladder cancer staging should preferably start with MRI followed by clinical staging. Unfortunately, however, because of the high cost of this strategy, MRI has to be reserved for staging deeply invasive and superficial poorly differentiated tumours.

MR imaging has proved value in the study of the female pelvis. In the past five years numerous reports from all over the world have testified to the superiority of MR imaging over Ultrasound (US) and Computed Tomography (CT) in the assessment of a wide range of conditions, including congenital abnormalities, benign or malignant tumors, and obstetrics. MR imaging should not only be used as a problem-solving modality, but also should have an immediate impact on treatment alternatives. Furthermore, the continuing advances in MR Imaging (e.g. development of new pulse sequences and surface coils) have imposed further demands on radiologists to familiarize with the current state of MR imaging. This article reviews the advantages, limitations, and unknown factors of some aspects of MR imaging of tumors in the female pelvis, including the use of contrast media, fast spin echo-imaging and surface coils.

Objective: The purpose of this study was to evaluate a magnetization prepared-rapid gradient-echo (MP-RAGE) sequence as a three-dimensional T1-weighted MR imaging technique for staging urinary bladder cancer and to compare this technique with a commonly used two-dimensional T1-weighted spin-echo sequence technique., Subjects and Methods: For 28 consecutive patients with urinary bladder cancer, MR findings and staging results were compared with histopathologic findings after surgery or autopsy. MR imaging was performed at 1.5 T with a Helmholtz double-surface coil. Conventional T1-weighted spin-echo, three-dimensional MP-RAGE, T2-weighted spin-echo or turbo-spin-echo, and dynamic T1-weighted fast gradient-echo sequences were used. Signal difference-to-noise ratios and T1 contrast were calculated by use of operator-defined regions of interest., Results: The signal difference-to-noise ratios for fluid-tumor and fat-tumor were, respectively, factors of 1.6 and 2.7 better with T1-weighted spin-echo sequences. T1 contrast of fluid-tumor was a factor of 2.6 better with three-dimensional MP-RAGE sequences, resulting in better recognition of small tumors, ascites, and dilated ureters. T1 contrast for fat-tumor was a factor of 2.0 better with T1-weighted spin-echo sequences. With the MP-RAGE sequence, motion artifacts were fewer in number than those noted with the T1-weighted spin-echo sequence, and susceptibility artifacts were equal in number to those noted with the T1-weighted spin-echo sequence. Using the three-dimensional technique, we performed off-line reconstruction of 1- to 2-mm high-resolution images in every desired plane. Because of higher spatial resolution, the availability of multiplanar reconstructions, and better fluid-tumor contrast and despite lower signal difference-to-noise ratios, three-dimensional MP-RAGE images resulted in better recognition of local tumor extension (n = 11), adhesions and bowel wall invasion (n = 5), lymph node metastases (n = 2), and bone marrow metastases (n = 2). The staging accuracy for the combination of three-dimensional MP-RAGE, T2-weighted, and dynamic sequences was 93%; that for the combination of two-dimensional T1-weighted spin-echo, T2-weighted, and dynamic sequences was 78%. Nodal staging was also more accurate with MP-RAGE sequences (accuracy of 93% vs 86% for T1-weighted spin-echo sequences)., Conclusion: Compared with two-dimensional T1-weighted spin-echo imaging, three-dimensional MP-RAGE imaging resulted in a 15% improvement in staging. Our findings suggest that optimal staging of urinary bladder carcinoma requires three-dimensional imaging techniques.

We describe 2 patients with simple transposition of the great arteries in whom coarctation of the aorta developed after uncomplicated arterial switch operation. Both patients showed no symptoms or signs of this coarctation at the time of arterial switch operation.

Pulmonary function tests were performed before surgery on 152 patients who were operated on for pectus excavatum between 1970 and 1987 and at long-term follow-up to assess the degree of impairment and to investigate any changes caused by surgical correction. The mean age at surgery was 15.3 +/- 5.5 years. Pulmonary function was found to be restricted preoperatively. Multivariate analysis showed that preoperative pulmonary function was not related to age, the severity of the deformity at physical examination, or to pulmonary complaints. Only the patients with obstructive disease showed significantly more pulmonary complaints (p = 0.042). The total lung capacity (TLC) and inspiratory vital capacity (IVC) were significantly related to the age-corrected (delta) anteroposterior diameter of the chest (lower vertebral index [LVI]) (p = 0.0001). At follow-up (mean, 8.1 +/- 3.6 years), the restriction of pulmonary function was increased despite improvement in the symptoms of most patients and despite a significant increase in the anteroposterior diameter of the chest (p = 0.0001): the TLC was decreased from 83.7 percent predicted (pred) preoperatively to 73.8 percent pred (p = 0.0001) and the IVC from 78.3 percent pred to 70.7 percent pred (p = 0.0001). The surgical results were satisfactory in 83.6 percent. No relation was found between the changes in pulmonary function measured at follow-up and the surgical results. Only the age at surgery and the changes in the TLC and IVC at follow-up were significantly related (p = 0.0036, 0.0043, respectively), although the correlation coefficients were low (r = 27 percent and 28 percent, respectively). The reduction in lung function at follow-up was most pronounced in the patients who had the least functional impairment (TLC > 75 percent pred) preoperatively. No correlation was found between the changes in the pulmonary function test results at follow-up and follow-up interval, preoperative delta LVI, and the change in delta LVI at follow-up.

In 35 patients with pectus excavatum (aged 17.9 +/- 5.6 years) pulmonary function and maximal exercise test results were compared before and at 1 year after operation. The lower posteroanterior chest diameter on the lateral x-ray film was significantly smaller than normal (p < 0.0001) and increased significantly after operation (p < 0.0001). Preoperatively, total lung capacity (86.0% +/- 14.4%; p = 0.0001) and inspiratory vital capacity (79.7% +/- 16.2; p = 0.0001) were significantly smaller than predicted and further decreased after operation (-9.2% +/- 9.2%; p = 0.0001 and -6.6% +/- 10.7%; p = 0.0012, respectively). Arterial blood gas values displayed normal patterns with increasing exercise both before and after operation. Only the arterial pH decreased more after operation than before (p = 0.0026). After operation there was a significant increase in maximal oxygen uptake (oxygen uptake; p = 0.0002 and oxygen uptake per kilogram; p = 0.0025) and oxygen pulse (oxygen uptake/heart rate approximates an indirect parameter for stroke volume; p = 0.0333) during exercise, whereas the maximal work performed was unchanged. Efficiency of breathing (ratio of tidal volume/inspiratory vital capacity) at maximal exercise improved significantly after operation (p = 0.0005). Ventilatory limitation of exercise (defined by an increase in carbon dioxide tension during exercise) was found in 43.9% of the patients before operation. A tendency of improvement was noted (not significant) after operation (difference in carbon dioxide tension 0.6 +/- 0.4 kPa before versus 0.3 +/- 0.5 kPa after operation). However, the group with normal preoperative carbon dioxide elimination had a ventilatory limitation of exercise after operation (difference in carbon dioxide tension -0.4 +/- 0.3 kPa before versus -0.1 +/- 0.3 kPa after operation; p = 0.0128) with a significant increase in oxygen consumption (p = 0.0007). In conclusion the subjective physical improvement after operation is not explained by changes in cardiorespiratory function at exercise. The data suggest a higher work of breathing after operation.

Objective: To evaluate the effectiveness of endorectal surface coil (ERC) magnetic resonance imaging (MRI) in the local staging of adenocarcinoma of the prostate (ACP)., Materials and Methods: A total of 23 patients who were considered candidates for radical prostatectomy because of clinically localized ACP were examined by ERC-MRI. All patients underwent laparoscopic or open lymph-node dissection prior to surgery. Four patients had positive lymph nodes at operation. A total of 19 underwent radical prostatectomy, allowing comparison of the MRI data with the surgical pathologic findings., Results: Twelve patients had extraglandular spread of ACP (T3) and 7 had locally confined ACP (T2). ERC-MRI predicted correctly a T3 tumor in 10 of 12 cases and a T2 tumor in 4 of 7 cases. ERC-MRI was 74% accurate in differentiating T2 from T3 tumor. Three cases of overestimation were in studies with poor image quality because of bowel movement motion artifacts., Conclusion: ERC-MRI was found to be a sensitive modality in staging clinically localized ACP.

The role of magnetic resonance (MR) imaging in the management of carcinoma of the urinary bladder is reviewed and illustrated. In vivo and in vitro MR images of the normal urinary bladder, carcinoma, and surrounding structures are presented. Factors for optimal MR imaging of urinary bladder carcinoma are reviewed. Pulse sequence optimization, (endorectal) surface coils, and other new developments such as fast spin echo, subtraction turbo-fast low angle shot (FLASH), three-dimensional rapid acquisition gradient echo sequences, and the use of contrast agents are discussed. Finally, the value of MR imaging in staging urinary bladder carcinoma is compared with clinical staging, staging based on findings from computed tomography and intravesical sonography.

In this article, the role of MR imaging in the management of carcinoma of the urinary bladder is reviewed and illustrated. The appearance of the normal urinary bladder and of bladder carcinoma on MR images is shown. Important factors for optimal MR imaging of urinary bladder carcinoma are reviewed. New developments such as three-dimensional and fast spin-echo sequences and the use of contrast agents, endorectal imaging, and phased array coils are discussed. Finally, the value of MR imaging in the staging of bladder carcinoma is described, and MR staging is compared with clinical staging, staging based on findings from intravesical sonography, and CT staging.

MRI with its excellent contrast resolution and direct multiplanar imaging has become a valuable medical tool in diagnostic imaging. Due to physiological motion artifacts, the role of MRI in the abdomen is still under discussion. The use of ultrafast sequences and the development of oral contrast agents, however, offers new promises for abdominal MRI. In the area of the retroperitoneum and pelvis, MRI produces excellent images as motion-artifacts are absent. Up to the end of 1989 clinical MRI in The Netherlands was performed in only four University hospitals; nevertheless these centers proved able to compete with international standards. The rapidly increasing number of MR units that recently became available in The Netherlands could result in a surpassing of CT in many pelvic and abdominal pathological conditions.

Marfan's syndrome is a connective tissue disorder, which mainly affects the cardiovascular system, together with ocular, skeletal and connective tissue. The cardiovascular manifestations in particular determine the mortality of this disorder. We studied 13 patients, suffering of Marfan's syndrome, with suspected aortic dilatation by means of magnetic resonance imaging (MRI). Aneurysmal dilatation of the aortic root and dissection were the two major findings in our study. Two of the five patients with dissections presented without relevant symptoms in the medical history nor at the time of the MRI examination.

The aim of this study was to evaluate tests predicting renovascular hypertension. This was done by relating the results of renal vein renin tests, the captopril test, and renal scintigraphic tests to the blood pressure outcome 12 months after relief of renal artery stenosis by percutaneous transluminal renal angioplasty in 31 patients. Cure was seen in eight (26%). Improved blood pressure was obtained in 12 patients (39%), and in 11 patients (35%), the result for blood pressure was a failure. The accuracies of the two mathematical models used to analyze the renal vein renin assays were 44% and 60%. The captopril test showed a sensitivity of 36% and an accuracy of 43%. Renal captopril technetium Tc 99m-labeled pentetic acid scintigraphy gave a sensitivity of 60%. Stepwise logistic regression analysis of clinical variables in relation to blood pressure response revealed age as the only factor significantly related to blood pressure outcome. We conclude that the tests used are unfit for helping select patients for percutaneous transluminal renal angioplasty and that age may have an important influence on outcome.

We describe a patient with haemoptysis 13 and 22 years after thoracotomy for a leiomyoma of the oesophagus. Despite extensive evaluation we did not get a firm diagnosis. The findings at bronchoscopy and microscopy suggested the possibility of a bronchial adenoma. At exploratory thoracotomy we found an intrapulmonary torn-off tip of a pleural drain. In retrospect, this foreign body was recognizable on the lung tomogram, the computerized tomogram and the magnetic resonance image. We discuss the diagnostic approach of a patient with non-massive haemoptysis.

Extramedullary plasmacytomas are uncommon manifestations of plasma cell neoplasms, which occur rarely in the urinary tract. We report to our knowledge the third case of primary IgA plasmacytoma of the urethra. Diagnosis, therapy and followup with magnetic resonance imaging are presented.

Acute purulent pericarditis in children is usually fatal, if not recognized and adequately treated. The history of three children with acute purulent pericarditis is presented. In every septic child who presents with signs of right heart decompensation, acute purulent pericarditis should be seriously considered. Echocardiography is essential for the diagnosis. If possible, diagnostic pericardiocenthesis should be performed. Experience of the last years suggests that excellent results can be obtained when adequate surgical drainage and antibiotic therapy are combined.